FIELD CROP TESTING AND MANAGEMENT IN SOUTHWESTERN COLORADO

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0151587
• Project Start Date: Jul 1, 2010
• Project End Date: Jun 30, 2015
• Program Code: [(N/A)]- (N/A)

Recipient Organization
COLORADO STATE UNIVERSITY
(N/A)
FORT COLLINS,CO 80523

Performing Department
Soil and Crop Science

Non Technical Summary
Sunflower has been grown commercially in southwestern Colorado since 2006 after the San Juan Bioenergy Company was formed. San Juan Bioenergy built an oilseed crushing plant in Dove Creek and began processing sunflower and safflower seeds in December 2008. Safflower has been grown in southwestern Colorado and particularly in southeastern Utah longer than sunflower has but its acreage rarely exceeds 2,000 hectares. Both safflower and sunflower have root systems that are capable of extracting soil moisture from great depths e.g., 2.0 m for sunflower based on the literature. This is a concern because of the low and erratic precipitation in southwestern Colorado. Long-term average annual precipitation in most of the farming area is 300 to 400 mm, 35 to 40% of which comes in the form of snow. Thus, a primary objective of this project is to determine the agronomic and economic feasibility of sunflower in rotation with more traditional crops such as winter wheat and dry bean. An important question that will be addressed is how often (e.g., every third or fourth year) can sunflower be grown in the same field while maintaining or enhancing the overall cropping system's profitability. Since sunflower is a relatively new crop in southwestern Colorado, we will also develop other best management practices such as optimum planting dates to maximize oil production for example. Most of the sunflower grown in southwestern Colorado is rain-fed, which given current production levels (a little over 1.5 million liters of oil in 2008) will not satisfy the Dove Creek Plant's capacity of 9.45 million liters of oil per year, unless dramatic increases in planted acres or oil yield occur. Consequently, we will experiment with limited but well targeted irrigation water applications as a way to boost oil production. In addition we will continue testing varieties and hybrids of sunflower and safflower for their adaptation and yield potential. Other oilseed crops of interest are canola and camelina. Canola has done well at the Southwestern Colorado Research Center under irrigation while camelina is a promising crop for dryland cropping systems given its short season and low input requirements. The information generated by this project will be shared with growers and recommendations will be made to enhance oilseed production in particular and agricultural sustainability in general, in southwestern Colorado.

Animal Health Component

(N/A)

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
111	0210	1060	10%
205	1410	1060	10%
205	1540	1060	10%
205	1541	1060	10%
205	1843	1060	10%
205	1844	1060	30%
205	1848	1060	10%
205	1849	1060	10%

Knowledge Area
111 - Conservation and Efficient Use of Water; 205 - Plant Management Systems;

Subject Of Investigation
1410 - Beans (dry); 1540 - Hard red winter wheat; 0210 - Water resources; 1541 - Hard red spring wheat; 1849 - Cuphea; 1848 - Canola; 1843 - Safflower; 1844 - Sunflower;

Field Of Science
1060 - Biology (whole systems);

Keywords

crop testing

alfalfa

camelina

canola

dry bean

sunflower

safflower

wheat

dryland crop rotations

planting date

limited irrigation

drip irrigation

Goals / Objectives
Objectives: (1) Test the performance and adaptation of several crops to the soil and climate of southwestern Colorado. The focus will be on oilseed crops such as sunflower, safflower, canola, and camelina; (2) Determine the feasibility of sunflower in rotation with traditional and alternative crops in southwestern Colorado; (3) Develop best management practices for optimum crop production with limited irrigation. Expected Outputs: (1) The identification of crops and crop varieties that are adapted to the soil and climate of southwestern Colorado and have desirable characteristics such as resistance or tolerance to certain diseases and insects, superior or stable seed or oil yield, and improved seed or oil quality; (2) The development of guidelines as to (a) Dryland crop sequences which include sunflower that maintain or enhance the cropping system's overall productivity and economic benefits, (b) Optimum planting dates and seeding rates of sunflower and other oilseed crops, (c) Expected response of sunflower and other crops to irrigation application amount and timing, and (d) Strategies to manage limited irrigation water supplies; (3) The communication of research results to growers and other interested parties to help them make informed decisions. Research-based results and recommendations will be published in AES technical reports and bulletins and presented at field days, workshops, and meetings.

Project Methods
The objectives stated above will be achieved by conducting well planned field trials at the Southwestern Colorado Research Center, making well defined measurements and observations, carefully analyzing and interpreting the data, and disseminating the results to a wide audience. Collaboration with growers, Extension and other CSU faculty, soil and water conservation districts, and others will be sought to accomplish specific objectives and arrive at mutually beneficial outcomes. Objective no. 1 will be a continuation of on-going testing of released and experimental varieties of sunflower, safflower, winter canola, camelina, and winter and spring wheat. Other crops such as dry bean will be tested based on needs and available resources. Seed yield, seed oil and/or protein content will be measured along with important characteristics such as plant height, flowering date, lodging, and susceptibility to frost, hail, disease and insect damage. Sunflower is a newly introduced crop; therefore there is an urgent need to develop cropping systems best suited to the soil and climatic conditions of SW Colorado. It is a deep-rooted crop capable of extracting soil moisture down to 1.8 m or deeper, which can have a big impact on other crops in the rotation. Several dryland crop rotations such as winter wheat-sunflower-fallow and winter wheat-dry bean-sunflower-fallow will be tested over a minimum of five years (Objective no. 2). Soil water and nutrient availability, crop yields, and the incidence of weeds, insects, and diseases will be monitored. Other tests will be conducted to determine the optimum planting dates or seeding rates of sunflower and other oilseed crops. Water being the most limiting production factor in SW Colorado, we will explore ways to optimize crop water use efficiency with sound irrigation scheduling and/or improved irrigation systems such as drip irrigation (Objective no. 3). Crops of interest will include alfalfa (high water user) and sunflower and the goal for example will be to boost sunflower oil production with limited but targeted irrigation applications.

Progress 07/01/10 to 06/30/15

Outputs
Target Audience:Agricultural producers Extension Agents Agricultural professionals Peer scientists Students Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One graduate student did part of her M.S. research at the Southwestern Colorado Research Center (Research Center).I attended the Western Regional Professional Improvement Conference in Ft. Collins, CO in 2013.Several students from the Cortez Open High School, the Dove Creek High School, Fort Luis College worked or visited the Research Center as part of their curriculum. I hosted, organized or participated to training or educational workshops on renewable energy, soil health, forage crops, native plants, alternative crops, and irrigation. I took webinars related to pesticide application training, cover crops, and water. I reviewed over 40 manuscripts and grant proposals and authored or co-authored eight grant proposals and two pre-proposals. I served as a judge at two local and three regional science and engineering fairs. How have the results been disseminated to communities of interest?This project resulted in at least 24articles in eight technical reports, one technical bulletin, and three peer-review journals. Research results were presented at 15 growers' and local meetings, 14 state and national meetings, three workshops and seminars, and five fields days. Numerous groups and individuals visited the Research Center and learned about specific research and demonstration projects. Several of these projects were also featured in the local media. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Numerous crops, crop varieties, and experimental lines were tested for their performance and adaptation to the soils and climate of southwestern Colorado under irrigated and non-irrigated conditions. Grain yields and other measured parameters (e.g., plant height, flowering date, and grain protein or oil content) varied from year to year due to precipitation amount and distribution, management practices, and other variables. We showed that several winter wheat varieties developed by Colorado State University (CSU) were among the most performing varieties even though they lacked resistance to dwarf bunt (Tilletia controversa), which is more of a concern in southwestern than in eastern Colorado where most CSU varieties are grown. For example, grain yields as high as 5353 kg/ha were achieved in 2015 at the Research Center with 'Byrd' hard red winter wheat, with no irrigation. Similar trends were observed on farmers' fields. Spring malting barley did poorly in 2013 with no irrigation. It performed well with irrigation in 2014 and 2015 and met all the quality standards for malting. Malting barley shows promise as an alternative crop for southwestern Colorado but unless there are winter varieties that perform well in our environment, it should only be grown under irrigation. Particular care should be given to N fertilizer management and irrigation scheduling to help meet the quality standards for malting. Another alternative crop that is well suited to the cropping systems in southwestern Colorado is winter canola. Winter canola is similar to winter wheat in the sense that it is planted and harvested around the same time, using the same equipment. But because of its smaller seed size, it is planted at a shallower soil depth (usually less than 2.5 cm), which makes it more susceptible to dry conditions during stand establishment. Seed yields averaged around 1000 kg/ha in the last several years, with no supplemental irrigation.The highest yield was 3760 kg/ha in 2015 with 31 out of 36 varieties exceeding 3300 kg/ha. Oil seed content wasaround 36%. Other alternative crops that have been tested and show good adaptation and yield potential include corn, safflower and sunflower. Corn is grown for grain at lower elevations (e.g., below 1800 m) but our research has shown that it may also be a viable crop at the higher elevations of southwestern Colorado (e.g., 1800 to 2100 m), particularly with supplemental irrigation.Advances in breeding and genetics (e.g., early maturity and drought tolerance) have made this possible. Safflower is usually grown in dryland cropping systems but irrigation can boost the yield greatly as was the case in 2012 (825 vs. 3064 kg/ha).Dryland sunflower did best when planted between 20 May and 10 June and after winter wheat in a wheat-sunflower-fallow rotation. Irrigating sunflower mostly during the reproductive growth stage (R-1 to R-6) produced as much as 88% of the seed yield of the fully-irrigated sunflower with 40% less water. When water supply is limited as is often the case in southwestern Colorado, applying water efficiently and at the most sensitive growth stages will help conserve water and increase water use efficiency. In the case of alfalfa, which is the largest irrigated crop in southwestern Colorado and the one that uses the most water, terminating irrigation after the second cutting instead of the first cutting may cause the least damage to alfalfa stand and yield. This was part of an on-going study that seeks to establish parameters for conserving water in western Colorado and possibly leasing it to M&I users without harming agriculture.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Update on Colorado Water Bank Project: First year of results on agronomic impacts and measurements of water savings. Dr. Perry Cabot , Dr. Joe Brummer, Dr. Calvin Pearson, Lyndsay Jones, Dr. Greg Litus, Dr. Abdel Berrada, Dr. Jos� Chavez, Colorado State University. 2015 Upper Colorado River Forum, October 29, 2015, Grand Junction, CO.
• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Agronomic Responses of Grass and Alfalfa Hayfields to No and Partial Season Irrigation as Part of a Potential Colorado Western Slope Water Bank. Joe E. Brummer, Lyndsay P. Jones, Perry E. Cabot, Calvin H. Pearson, and Abdel F. Berrada, Colorado State University. 2015 AWRA Annual Water Resources Conference, November 16-19, Denver, CO.

Progress 10/01/13 to 09/30/14

Outputs
Target Audience: Farmers and ranchers, Extension agents, USDA-NRCS personnel, policy makers, water managers, peer scientists Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? The alfalfa and sunflower projects were highlighted at a field day on August 15, 2014; at our advisory committee meeting on February 12, 2014 and at a seminar at CSU-Ft. Collins on November 12, 2014. The results are included in CSU-AES Technical Report TR14-13. What do you plan to do during the next reporting period to accomplish the goals? The alfalfa-fallowing study will be continued in 2015 with added emphasis on water balance determination. This was the last year of the sunflower deficit irrigation study. The combined results from several years will be interpreted and published. Crop testing continues to be a major component of the research program at the Research Center. Malting barley, industrial hemp, and potatoes are some of the newer crops that will be tested in 2015.

Impacts
What was accomplished under these goals? This report addresses objective no. 3. Two field trials were conducted in 2014 to determine the response of alfalfa and sunflower to deficit irrigation. Alfalfa is a major and well established crop in southwestern Colorado. It has many economic and environmental benefits but it is a relatively high water user. Sunflower was re-introduced to southwestern Colorado in the mid-2000 as an alternative crop with value added potential. It requires less water than alfalfa for optimum seed production but like alfalfa, it has deep roots that can deplete soil moisture and nutrients to a depth of 2.0 m or more. Water supplies in southwest Colorado are hampered by low and erratic precipitation and frequent droughts, hence the importance of water management and conservation. The alfalfa trial is part of a larger study entitled “Assessing the agronomic feasibility of partial and full season hay fallowing as part of a Western Slope Water Bank” led by Dr. Joe Brummer. Stopping irrigation after the second cutting did not reduce alfalfa DM yield in 2013 compared with the fully irrigated treatment and it only reduced yield by 3.6% in 2014. The second cutting usually occurs in early August. When no irrigation water was applied after the first cutting, the drop in DM yield was 41% in 2013 and 73% in 2014. The same field was used in 2013 and 2014. Non-irrigated alfalfa produced 77% less DM in 2013 compared to the fully irrigated treatment. Rainfall in August and September was substantially above normal in 2013 and slightly above normal in 2014, which may explain the response to irrigation termination after the second cutting in 2013 and 2014. On average, August and September are the rainiest months in southwest Colorado. Therefore, when water supplies are limited, terminating irrigation after the second cutting may cause the least damage to alfalfa stand (data not reported) and yield. Sunflower was subjected to four irrigation regimes, pre-plant irrigation only (I-1), full irrigation (I-2), irrigation from bud initiation through flowering (I-3), and irrigation during flowering (I-4). All the treatments received 4.6 cm of net irrigation water prior to planting sunflower. Treatment I-2 received an addition 40.9 cm of irrigation water from planting to physiological maturity to meet ET, which added up to 54.0 cm. Treatment I-3 received 22.0 cm and I-4 8.6 cm. Rainfall from planting to physiological maturity was 13.6 cm. The full irrigation treatment I-2 averaged 2337 kg/acre, significantly more than I-3 (1984 kg/acre), I-4 (1955 kg/acre), and I-1 (1036 kg/acre). Treatment I-4 had the highest water use efficiency (29 kg/cm), followed by I-1 (22 kg/cm), I-3 (20 kg/cm), and I-2 (16 kg/cm). This is consistent with previous years’ results which indicate that when water supply is limited, applying most of the irrigation water during the reproductive stages will produce the most return in terms of seed production.

Publications

• Type: Other Status: Accepted Year Published: 2015 Citation: Berrada, A., and J. Schneekloth 2014. Boosting sunflower production in SW Colorado with supplemental irrigation2013 result summary. p. 2528 In Agric. Exp. Sta. Tech. Rep. TR14-13, Colorado State Univ., Ft. Collins, CO.
• Type: Other Status: Accepted Year Published: 2015 Citation: Jones, L., J. Brummer, C. Pearson, and A. Berrada. 2014. Agronomic responses to partial and full season fallowing of alfalfa and grass hayfields. p. 3839 In Agric. Exp. Sta. Tech. Rep. TR14-13, Colorado State Univ., Ft. Collins, CO.
• Type: Other Status: Accepted Year Published: 2015 Citation: Berrada, A., K. Dillivan, and R. Hammon 2014. Evaluation of sunflower in dryland cropping systems. p. 2024 In Agric. Exp. Sta. Tech. Rep. TR14-13, Colorado State Univ., Ft. Collins, CO.

Progress 01/01/13 to 09/30/13

Outputs
Target Audience: Agricultural producers, Extension agents, USDA-NRCS personnel, peer scientists Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Some of the results were presented at our 2012 and 2013 advisory committee meetings and published in CAES Technical Reports TR12-7 and TR13-8. The results of this project were also presented at the National Sunflower Association Research Forum in January 2013 and 2014. What do you plan to do during the next reporting period to accomplish the goals? We will pursue all three objectives listed under "Majors goals of the project", publish the 2013 results in a CAES Technical Report, and prepare a manuscript to publish the results of objective no. 3.

Impacts
What was accomplished under these goals? Objective no. 2 is the focus of this progress report. This project was sponsored by the National Sunflower Association. A field trial has been conducted at the Southwestern Colorado Research Center since 2011 to assess the feasibility of sunflower in dryland crop rotations. In 2013, sunflower averaged 893 kg seeds/ha, which is slightly above the 3-year average of 855 kg/ha. The estimated average annual crop value of sunflower was $478/ha, which was below that of corn for grain, winter wheat, and safflower, but above the value of dry bean, corn for forage, and camelina. Sunflower did best when grown after winter wheat. It produced 1301 kg/ha compared to 617 kg/ha when it was grown after dry bean. Dry bean did poorly in 2013 due to drought early in the season and hail during the second week of September. Corn in 2013 benefited from above average precipitation in August and September. It produced 3875 kg of grain/ha with an estimated value of $1098/ha. However, the yield of corn has been unreliable and corn prices have been on the decline since early 2013. In 2012, which was a dry year, corn failed to produce much grain. Crop rotations including sunflower did better than other crop rotations in 2011-2013. The winter wheat-sunflower-fallow rotation did the best with an annualized crop value of $376/ha, followed by winter wheat-opportunity crop-sunflower-fallow, winter wheat-dry bean-sunflower-fallow, and winter wheat-safflower-fallow at around $346/ha. The opportunity crop was camelina in 2011 and corn in 2012 and 2013. Winter wheat followed by two years of dry bean and one year of fallow had the lowest yearly crop yield of 720 kg/ha. It had a somewhat higher value ($306/ha) than the standard winter wheat-fallow crop rotation ($286/ha). Dry bean after dry bean has not done well so far in this experiment. More testing and more agronomic and economic analyses will be done in 2014 and 2015 before making recommendations as to which dryland cropping rotations are feasible in SW Colorado.

Publications

• Type: Other Status: Published Year Published: 2013 Citation: Berrada, A. (ed.). 2013. Southwestern Colorado Research Center2012 Results. Agric. Exp. Sta. Tech. Rep. TR13-8, Colorado State University, Ft. Collins, CO. Berrada, A., and Reich, D. 2013. Evaluation of Corn Hybrids for Drought Tolerance. p. 15-22 In Agric. Exp. Sta. Tech. Rep. TR13-8, Colorado State Univ., Ft. Collins, CO. Berrada, A. and Schneekloth, J. 2013. Boosting Sunflower Production in SW Colorado with Supplemental Irrigation: 2012 Result Summary. p. 28-33 In Agric. Exp. Sta. Tech. Rep. TR13-8, Colorado State Univ., Ft. Collins, CO. Berrada, A., Dillivan, K., and Hammon, R. 2013. Evaluation of Dryland Crop Rotation that Include Sunflower: 2012 Result Summary. p. 25-27 In Agric. Exp. Sta. Tech. Rep. TR13-8, Colorado State Univ., Ft. Collins, CO. Hooten, T., Dillivan, K., Fernandez, D., and Berrada, A. 2013. Yellow Jacket Fruit Tree Research and Demonstration Project: 2012 Report. p. 34-40 In Agric. Exp. Sta. Tech. Rep. TR13-8, Colorado State Univ., Ft. Collins, CO. Berrada, A., and Schneekloth, J. 2013. Response of sunflower to deficit irrigation. Irrigation Show 2013, Nov. 4-8, 2013, Austin, TX. Irrigation Association, Falls Church, VA. Berrada, A. 2013. Review of sunflower water management research. Western Society of Crop Science, 2013 Annual Meeting, Jun. 11-12, Pendleton, OR Berrada, A. 2013. Opportunities and challenges for oilseed crops in SW Colorado. 2013 National Association of County Agricultural Agents/Western Regional Professional Improvement Conference, Oct. 9-10, 2013, Ft. Collins, CO.

Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Water is the most limiting factor of crop production in SW Colorado due to low and erratic precipitation and frequent droughts. Water allocation was reached or exceeded 38% of the time in the full service area of the Dolores Project since water was delivered to farms in 1987, thus the importance of water conservation and management. A field experiment was conducted at the Southwestern Colorado Research Center in 2012 to test the response two sunflower hybrids, Mycogen H449CLDM and Triumph s870HCL to four irrigation treatments (I-1, I-2, I-3, and I-4) and four N rates (0, 34, 67, and 101 kg N/ha). All the treatments received 6.4 cm (net amount) of water prior to planting sunflower and 11.2 cm of rainfall during the growing season. Treatment I-1 received no additional irrigation water while I-2 (irrigation to meet crop ET throughout the growing season), I-3 (irrigation at growth stages R-1 to R-6), and I-4 (irrigation at R-4 to R-6) received an additional 41, 22, and 11 cm of water, respectively. Irrigation treatment I-2 averaged 3041 kg/ha, followed by I-3 at 2685 kg/ha, I-4 at 1733 kg/ha, and I-1 at 1081 kg/ha. Mycogen 8H449CLDM averaged 2290 kg/ha compared to 1979 kg/ha with Triumph s870HCL. The latter also had significantly lower seed and test weights. Treatment I-2 had the highest seed oil content of 43.8%, significantly more than I-3 and I-4. Treatment I-1 had the lowest oil content. Mycogen 8H449CLDM and Triumph s870HCL averaged 43.2% and 41.9%, respectively. Birds caused the most damage at I-2 with H449CLDM (9% seed loss) and the least damage at I-4. Hybrid H449CLDM averaged 103 cm in height compared to 66 cm for s870HCL. The full irrigation treatment I-2 produced the tallest plants while I-4 and I-1 produced the shortest plants. The application of 34 to 101 kg N/ha had no significant effect on seed yield, oil content, plant height, seed weight or test weight, nor did N by Irrigation or N by Hybrid interactions, possibly because not all the residual N in the root zone was accounted for. PARTICIPANTS: Participants include Joel Schneekloth (co-PI), Amin Berrada (technical assistance), and Jerry Mahaffey (assistance with planting and harvest). Partners include the National Sunflower Association (sponsor) and the Dolores Water Conservancy District (co-sponsor). Training includes participation to the National Sunflower Research Forum, tours of the field trial by ag industry representatives, students, and others; and professional development for staff through direct participation to the project. TARGET AUDIENCES: Target audience include Farmers, Extension agents, USDA-NRCS, and Ag industry representatives. Efforts include presentation of results at the Advisory Board Meeting, Growers Information Meeting, and Renewable Energy Workshop. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Sunflower is still a minor crop in SW Colorado but the potential exists for increased production with limited but well targeted irrigation application. Applying water from the beginning of the reproductive stage through flowering (I-3) produced 2685 kg/ha with 46% less irrigation water than the full-irrigation treatment I-2. In 2011, I-3 performed as well as I-2. Sunflower would be a good alternative to small grains in rotation with alfalfa, which is the main irrigated crop in SW Colorado. With its deep root system, sunflower would mine residual N and water that may be out of reach of spring wheat, oat, or dry bean. The short stature hybrid Triumph s870CL averaged 311 kg/ha less seed than Mycogen 8H449CLDM but it is more suitable to irrigation with siderolls, which are prevalent in SW Colorado.

Publications

• Stamm, A., Berrada, A., Buck, J., Cabot, P., Claassen, M., Cramer, G., Dooley, S.J., Godsey, C., Heer, W., Holman, J., Johnson, J., Kochenower, R., Krall, J., Ladd, D., Moore, J., O'Neill, M.K., Pearson, C., Phillips, D.V., Rife, C.L., Santra, D., Sidwell, R., Sij, J., Starner, D., and Wiebold, W. 2012. Registration of 'Riley' Winter Canola. Journal of Plant Registrations, Vol. 6, No. 3, September 2012.
• Berrada, A.F., and Halvorson, A.D. 2012. Manure and nitrogen fertilizer effects on corn productivity and soil fertility under drip and furrow irrigation. Archives of Agronomy and Soil Science 58 (10-12): 1329-1347. Pearson,C.H., Ogg, J.B., Brick, M.A., and Berrada, A. 2012. Popping and Yield Characteristics of Nuna Bean Lines Developed for Temperate Climates. Agron. J. 104:1574-1578.
• Berrada, A. (ed.). 2012. Southwestern Colorado Research Center 2011 Research Report. Agricultural Experiment Station Technical Report TR12-7, Colorado State University, Fort Collins, CO.
• Berrada, A. 2012. Boosting sunflower production in SW Colorado with supplemental irrigation--2011 Result summary. p. 38-44 In Agricultural Experiment Station Technical Report TR12-7, Colorado State University, Fort Collins, CO.
• Johnson J.J., Hain, J., Berrada, A., Sauer, S., and Jewell, K. 2012. Making Better Decisions, 2012 Colorado Sunflower Performance Trials. Agricultural Experiment Station Technical Report TR12-14, Colorado State University, Fort Collins, CO.
• Bartolo, M.A., Berrada, A., and Johnson, J., 2012. Alfalfa Variety Performance Test at Rocky Ford- 2009. Arkansas Valley Research Center 2009 Reports. p.2-3 In Agricultural Experiment Station Technical Report TR12-5, Colorado State University, Fort Collins, CO.

Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Sunflower has been grown commercially in southwestern (SW) Colorado since 2006, mostly on dryland. Low and erratic precipitation combined with little or no fertilizer application generally results in low seed yields. Previous research in SW Colorado and elsewhere has shown good response to supplemental irrigation and to nitrogen (N) fertilizer. There are over 60,000 ha of irrigated cropland in SW Colorado. Hence, the potential exists for increased sunflower production with limited but well targeted irrigation application and with N fertilizer. A field trial was conducted at the Southwestern Colorado Research Center in 2011 to test sunflower response to irrigation scheduling and N rate. Five irrigation treatments (I-1, I-2, I-3, I-4, and I-5) and three N rates (0, 56, and 112 kg N/ha) were applied in a RCB design with four replications. All the irrigation treatments received 8.1 cm of water prior to planting sunflower and during stand establishment and a total of 13 cm of rainfall. Treatment I-1 received no additional irrigation water while I-2 (irrigation to meet crop ET throughout the growing season), I-3 (irrigation at growth stages R-1 to R-6), I-4 (irrigation at R-4 to R-6), and I-5 received an additional 39, 23, 12, and 6 cm of water, respectively. Treatment I-5 consists of irrigating sunflower until it gets too tall to irrigate with a linear-move sprinkler irrigation system, also known as sideroll. Siderolls are the most common irrigation water-delivery system in SW Colorado. Irrigation mostly from pre-bud through bloom (I-3) produced 3442 kg seeds/ha, which was comparable to that of the full irrigation regime I-2. Irrigation mostly during flowering (I-4) produced 3224 kg/ha, similar to I-3 but significantly more than I-5 and I-1. Oil content varied significantly in the same order: I-2 = I-3 ≥ I-4 > I-5 > I-1. Sunflower plants averaged 116 cm in height with I-1 and I-4 and 130 cm with I-2, I-3, and I-5. Thus, restricting irrigation mostly to the flowering period (I-4) reduced plant growth but did not negatively impact seed yield or oil content compared to I-3. For every centimeter of water (irrigation plus rain) received, I-4 produced 99 lb of seeds per ha. In comparison, I-2 produced 58 lb/cm and I-3 79 lb/cm. Seed yield increased from 2744 kg/ha with no N fertilizer application to 2992 kg/ha with the addition of 56 kg N/ha. Seed oil content decreased from 40.3% with the check to 39.1% with 112 kg N/ha. PARTICIPANTS: This project was funded by Colorado State University's Agricultural Experiment Station, the National Sunflower Association, and the Dolores Water Conservancy District. Collaborators include Joel Schneekloth of Colorado State University. TARGET AUDIENCES: Agricultural producers, Dolores Water Conservancy District, USDA-NRCS, Extension personnel, Colorado Sunflower Association, National Sunflower Association PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Sunflower is still a minor crop in SW Colorado but the potential exists for increased production with limited irrigation and N fertilizer. Applying water mostly during flowering increased seed yield by 55% compared to early-season irrigation. Irrigation efficiency (kg of seeds/cm of water/ha) increased by 70% compared to full irrigation. Seed yield also increased significantly with the application of 56 kg N/ha. Sunflower would be a good alternative to small grains in rotation with alfalfa, which is the main irrigated crop in SW Colorado. With its deep root system, sunflower would mine residual N and water that may be out of reach of spring wheat, oat, or dry bean. Irrigation during flowering would increase seed and oil yields substantially. The latter can only be achieved with short-stature sunflower hybrids if water is delivered with siderolls, which are common in SW Colorado.

Publications

• Berrada, A. 2011. Adaptation of oilseed crops in Southwestern Colorado. 20-22 Jun 2011, Western Society of Crop Science & Western Society of Soil Science Joint Meetings, Laramie, WY.
• Berrada, A. (ed.) 2011. Southwestern Colorado Research Center 2010 Research Report. Agricultural Experiment Station Technical Report TR11-04, Colorado State University, Ft. Collins, CO.
• Berrada, A., and Reich, D. 2011. Alfalfa Irrigation Water Management. Pages 127-134 In Intermountain Grass and Legume Forage Production Manual, 2nd Edition, Agricultural Experiment Station and Extension Technical Bulletin TB11-02, Colorado State University, Ft. Collins, CO.
• Berrada, A., and Schneekloth, J. 2011. Boosting Sunflower Production in SW Colorado with Supplemental Irrigation: 2010 Results. Pages 32-34 In Agricultural Experiment Station Technical Report TR11-04, Colorado State University, Ft. Collins, CO.
• Berrada, A., Haley, S., Brick, M., and Johnson, J.J. 2011. Field Crops Variety Performance Trials. Pages 10-31 In Agricultural Experiment Station Technical Report TR11-04, Colorado State University, Ft. Collins, CO.
• Johnson J.J., Hain, J., Berrada, A., Sauer, S., Jewell, K. 2011. Making Better Decisions, 2011 Colorado Sunflower Performance Trials. Colorado State University Agricultural Experiment Station Technical Report TR11-08.
• Pavlista, A.D., Santra, D.K., Isbell, T.A., Baltensperger, D.D., Hergert, G.W., Krall, J., Mesbach, A., Johnson, J., O Neil, M., Aiken, R., Berrada, A. 2011. Adaptability of Irrigated Spring Canola Oil Production to the US High Plains. Industrial Crops and Products 33:165-169 (2011).

Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: Sunflower was introduced to SW Colorado in 2006 after the San Juan Biodiesel Cooperative (it was later renamed San Juan Bioenergy LLC) was formed and started making plans to build an oilseed crushing plant in Dove Creek, CO. The plant became operational in December 2008 and with it, the need to develop sunflower best management practices intensified. Research in 2010 included sunflower hybrid performance, planting date, irrigation, and crop rotation trials. The hybrid performance trial averaged 2034 kg/ha and 38% oil concentration. Sunflower production in 2010 was enhanced by above average winter and summer precipitation, a relatively long growing season, and a low incidence of diseases and insects. In the planting date study, sunflower was planted on 18-May, 1-Jun, and 15-Jun. Planting sunflower on 15-Jun caused a significant decrease in seed yield, oil concentration, and test weight. The main objective of the irrigation trial was to quantify the response to limited irrigation. Irrigation treatments consisted of (I-1) Pre-plant irrigation (PPI) only, (I-2) PPI + Full irrigation to meet crop evapotranspiration demand, (I-3) PPI + Irrigation at growth stages R-1 to R-6, (I-4) PPI + Irrigation at R-4 to R-6, and (I-5) PPI + Irrigation until sunflower would have been too tall to irrigate with a linear-move sprinkler irrigation system, also known as sideroll. Siderolls are the most common irrigation water-delivery system in SW Colorado. All the treatments received 4.6 cm of irrigation water (net amount) prior to planting sunflower. Post-planting irrigation amounts were 0, 29.0, 7.9, 6.6, and 16.8 cm for I-1, I-2, I-3, I-4, and I-5 respectively. Water was applied with a sideroll before planting and with drip tapes after planting. The irrigation treatments were arranged in a randomized complete bloc fashion with four replications. Plot size was 3.0 m by 15.2 m. The full irrigation treatment (I-2) produced significantly more seeds (3321 kg/ha) than all the other treatments. I-3, I-4, and I-5 averaged 2911 kg/ha which was significantly more than I-1 (2614 kg/ha). Conversely, I-1 had the highest precipitation efficiency of 1.69 kg seeds/m3 of water from irrigation and rain, while I-2 was the least efficient in converting water to seed production (0.75 kg/ m3), followed by I-5 (0.90 kg/ m3). I-5 received most of the irrigation water vegetative growth. I-3 and I-4 averaged 1.28 kg/m3. The dryland crop rotation trial was initiated in the spring of 2010 to determine the effects of sunflower in rotation with other crops on crop yields, soil water and nutrient availability, and crop income. Six crop sequences are being tested. They are: winter wheat-Sunflower-Fallow, Winter wheat-Dry bean-Sunflower-Fallow, winter wheat-Opportunity crop-Sunflower-Opportunity crop, winter wheat-fallow, winter wheat-safflower-fallow, and winter wheat-dry bean-dry bean-fallow. Each phase of each crop rotation will be tested every year, in a randomized complete bloc design with three replications. Plot size is 9.1m x 50.9 m. Dry bean averaged 1000 kg/ha, safflower 1972 kg/ha, and sunflower 2015 kg/ha. The opportunity crop, camelina, was not harvested due to hail damage. PARTICIPANTS: Joel Schneekloth, co-PI, Regional Extension Specialist, Colorado State University, Akron, CO and Daniel Fernandez, co-PI, Dolores County Extension Director, Colorado State University, Dove Creek, CO and Rodney Sharp, co-PI, Extension Specialist/Agriculture and Business Management Economist, Colorado State University, Grand Junction, CO and National Sunflower Association, sponsor TARGET AUDIENCES: Agricultural producers, Extension personnel, NRCS staff, other interested residents of SW Colorado, Montezuma and Dolores Conservation districts, Dolores Water Conservancy and Southwestern Water Conservation districts, San Juan Bioenergy, sunflower seed companies, other agricultural businesses, and peer scientists PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
On average, 19.5% less seed (1490 vs. 1851 kg/ha) was produced in 2010 when sunflower was planted on 15 June compared to 18 May or 1 June, which represents a loss of $128/ha in gross income. Given the climate of SW Colorado (e.g., probability of last spring and first fall killing frosts), the optimum planting date of dryland sunflower in SW Colorado appears to be around late May. Limited but targeted irrigation application in 2010 increased sunflower seed yield and precipitation use efficiency significantly. More testing is required to confirm the 2010 results and recommend best water management practices for example. It is too early to draw conclusions.

Publications

• Berrada, A., Stack, M., Johnson, J. 2010. Sunflower variety performance trials at Yellow Jacket, CO. p. 48-60 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Berrada, A. 2010. Sunflower planting date by seeding rate by hybrid trial at Yellow Jacket, CO. p. 61-63 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Berrada, A., and Stack, M. 2010. Dryland safflower variety performance trials at Yellow Jacket, CO. p. 64-68 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Stack, M., and Berrada, A. 2010. Spring canola variety trials at Yellow Jacket, CO. p. 75-78 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Berrada, A. 2010. Spring canola irrigation trial at Yellow Jacket, CO. p. 79-80 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Enjalbert, J.N., Berrada, A., Stack, M., and Johnson, J. 2010. Camelina research at Yellow Jacket in 2008 and 2009. p. 81-86 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Stack, M., Berrada, A., Brick, M., and Johnson, J. 2010. Grain legumes: Dry bean research at the Southwestern Colorado Research Center. p. 87-94 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Berrada, A. 2010. Grain Cereals: Introduction. p. 18-21 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Stack, M., Berrada, A., Haley, S., and Johnson, J. 2010. Dryland winter wheat variety performance trials at Yellow Jacket, CO. p. 22-31 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.
• Berrada, A. 2010. Oilseed crops: Introduction. p. 39-47 In Berrada, A., and Stack, M. (ed.) Southwestern Colorado Research Center 2005-2009 Research Results, Agricultural Experiment Station Technical Report TR10-06, Colorado State University, Ft. Collins, CO.

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Agriculture in the Arkansas River Valley of SE Colorado (Ark Valley) is highly dependent on irrigation water due to low and erratic precipitation. Thousands of hectares of land have been dried out due to the sale and transfer of irrigation water to municipalities along the Front Range. This trend will likely continue but there is a push to lease water rather than sell it. Water quantity issues are exacerbated by quality concerns such as the relatively high salt, nitrate, or selenium concentrations in segments of the river or its aquifers. As water moves over the soil or through it, it dissolves and transports salts and other pollutants. Over 80% of cropland in the Ark Valley is furrow-irrigated, resulting in large quantities of runoff and drainage. More efficient irrigation systems and sound nutrient management should lead to water savings and reduced leaching of salts and nitrates. These principles were illustrated in 2007 and 2008. Soil moisture sensors were installed in several fields to assist growers manage their irrigation water. The sensors were connected to a data logger that displays the readings on a graph. A table giving the equivalent available soil moisture in inches of water per foot of soil and the readings at which irrigation is recommended was attached to each data logger. In addition, crop ET data from the nearest weather station was emailed to each cooperator on a weekly basis. Visits were made to each field regularly to check the sensors and discuss the readings with the cooperator. Field trials were conducted at the Arkansas Valley Research Center to further demonstrate improved water and nutrient management practices. Water was applied through a subsurface drip system as a fraction (50%, 75%, 100%, and 125%) of crop ET. The total amount of water applied was greater in 2008 than in 2007 (49.5 cm in 2008 vs. 28.7cm in 2007 at 100% ET) due to a late start in 2007. There was a linear increase in corn yield in 2007 as the water application rate increased. In 2008, corn yield leveled off at around 75% ET and dropped as irrigation application rate increased from 100 to 125% ET. In 2007, nitrogen (N) fertilizer was applied at two rates, the recommended rate of 134 kg N/ha and twice as much. All of it was broadcast and incorporated into the top soil before the crop (corn) was planted (pre-plant incorporated or PPI). In 2008, N fertilizer was either applied in its entirety as PPI or split between one PPI and three post-planting applications. In the 100% PPI treatment, N was applied at the recommended rate of 160 kg N/ha. In the split treatment, 34 kg N/ha were applied as PPI and the rest (67 kg N/ha) was injected through the drip system in three applications. The timing and rate of N application was determined with the help of a Chlorophyll meter. Hence, 59 kg N/ha were saved with this method. There was no significant difference in corn yield between the two N rates in 2007. Greater corn yield (15.4 Mg/ha) was produced with the split application method in 2008, compared to PPI (14.4 Mg/ha). There was less residual nitrate N in the fall of 2008 (85 kg N/ha) than in the fall of 2007 (29 kg/ha at 100% ET and the recommended N rate). PARTICIPANTS: Troy Bauder, Michael Bartolo, and James Valliant TARGET AUDIENCES: Agricultural producers, consultants, extension agents, and agency (NRCS, water districts, etc.) personnel PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Managing water in ways that preserve or enhance agricultural production in the Ark Valley, within the legal framework of the Arkansas River Compact, is a must! In this project, we demonstrated that: (1) Simple tools such as soil moisture sensors and crop ET can be used effectively to schedule irrigation, (2) Significant water conservation can be achieved with drip irrigation and sound irrigation scheduling. For example, similar corn yield was produced with 75% and 100% ET application rates. (3) Nitrogen fertilizer rates can be reduced substantially by taking into account soil test results and crop yield goal. Further gains were achieved by applying N through the drip system when the crop needed it, which lowered the potential for leaching of nitrate N below the root zone.

Publications

• Berrada, A. 2009. Conserving water and minimizing leaching of salts and nitrate-nitrogen in the Arkansas Valley through enhanced irrigation and nutrient management. Final project report (Unpub.). Colorado State University, Southwestern Colorado Research Center, Yellow Jacket, CO 81335.
• Andales, A., Straw, D., Ley, T., and Berrada, A. 2009. Alfalfa reference ET from a weighing lysimeter and estimates from the ASCE Standardized Reference ET Equation in the Arkansas Valley of Colorado. pp. 1-9 (342) In Steve Starrett (ed.) World Environmental and Water Resources Congress 2009: Great Rivers Proceedings of World Environmental and Water Resources Congress, May 17-21, 2009, Kansas City, Missouri.
• Berrada, A. 2009. Alfalfa Irrigation Management. In Forage Manual. Colorado State University--http://wci.colostate.edu/ForageManual/Chapter15.pdf

Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Agriculture in the Arkansas River Valley of southeastern Colorado (Arkansas Valley) has experienced water shortages due to droughts and the sale of irrigation water to municipal and industrial interests. Moreover, the predominant irrigation system in the Arkansas Valley, furrow irrigation, is known for its inefficiency (e.g., only 40 to 60% of the water applied to the field is used by the crop) and for its potential to leach salts and nitrates into the ground water. Research at the Arkansas Valley Research Center (AVRC) has shown that drip irrigation is a much more efficient system for applying water to crops such as onion and corn. However, any major changes in irrigation practices can alter the return flows to the river and jeopardize compliance with the Arkansas River Compact. In Kansas v. Colorado, U.S. Supreme Court Special Master Arthur Littleworth recommended that the ASCE Standardized Penman-Monteith equation (PME) be used to calculate crop consumptive use and improve the accuracy of the model used to determine how much water is due to Kansas each year. Consequently, the State of Colorado funded the construction and installation of two weighing lysimeters at AVRC. The project objectives are to: (1) Evaluate the performance and predictive accuracy of PME for computing the reference evapotranspiration (ETr) of a well-watered alfalfa crop, (2) Determine crop coefficients (Kc) for the major crops grown in the Arkansas Valley and, (3) Determine the effects of typical local growing conditions such as limited irrigation and salinity on crop water use. Crop water use can be calculated with the equation: ETc = ETr x Kc x Ks, where Ks is a stress coefficient that accounts for the relative availability of water in the root zone. Ks = 1 when there is no water stress. The larger of the two lysimeters was installed in 2007 and consists of an inner tank of 21.6 cubic meters (3.0 x 3.0 x 2.4 m) and an outer containment tank. The inner tank was filled with undisturbed soil from the same field where the lysimeter is located. It moves freely within the outer tank, which houses the weighing mechanism, the drainage tanks, and data loggers. The weighing mechanism consists of a mechanical lever scale-load cell combination. The load cells are connected to a Campbell Scientific CR-7 data logger that records the weight of the inner tank every 10 seconds with high accuracy. Several instruments were installed in, above, or around the lysimeter to measure soil, air, and crop temperature, soil heat flux, wind speed and direction, incoming and outgoing radiation, precipitation, and other parameters used to calibrate PME. A smaller lysimeter (1.5 x 1.5 x 2.4 m) is under construction and will be used exclusively to measure alfalfa reference ET. Data from a dozen weather stations will be used to adjust ETr values for the various conditions in the Arkansas Valley. The lysimeter project was visited by several groups and individuals in 2008 and was the subject of several presentations and publications. PARTICIPANTS: Colorado State University Agricultural Experiment Station: Lee Sommers, Frank Johnson, Michael Bartolo, Abdelfettah Berrada, Allan Andales, Brett Schaffer, Lane Simmons, and Kevin Tanabe. Colorado State University Colorado Water Institute: Reagan Waskom. Colorado State University Department of Civil Engineering: Timothy Gates and Luis Garcia. State of Colorado Division of Water Resources: Dale Straw and Thomas Ley. Colorado Water Conservation Board: Steve Miller. USDA-ARS in Bushland, TX and Fort Collins, Colorado. TARGET AUDIENCES: Target audiences include: policy makers in Colorado (Division of Water Resources, Colorado Water Conservation Board, etc.), research, teaching, and extension faculty from Colorado State University and other universities; USDA ARS and NRCS; civil and agricultural engineers; scientists; irrigation managers; farmers and water districts in the Arkansas Valley; consultants; and Arkansas River Compact stakeholders. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
No current impact.

Publications

• Andales, A.A., Berrada, A., Simmons, L., Bartolo, M., Straw, D., and Ley, T. 2008. Performance of the ASCE Standardized Reference ET Equation in the Arkansas Valley of Colorado. 2008 Joint ASA CSSA GSA HGS GCAGH SSSA Annual Meetings. 5-9 October 2008, Houston, TX.
• Berrada, A., Simmons, L., Bartolo, M., Straw, D., and Ley, T. 2008. The Large Lysimeter at the Arkansas Valley Research Center: Objectives and Accomplishments. Agric. Exp. Sta. Tech. Bull. TB08-02, Colorado State Univ., Ft. Collins, CO.
• Berrada, A., Simmons, L., Bartolo, M., Straw, D., and Ley, T. 2008. The lysimeter Project in Rocky Ford: Objectives and Accomplishments. Colorado Water 25 (1) : 8-12, Newsletter of the Water Center of Colorado State University, Jan./Feb. 2008, Ft. Collins, CO.
• Allan Andales and Abdel Berrada. 2008. The Lysimeter Project at Rocky Ford. From the Ground Up Agronomy News, 27 (2): 4-9. Cooperative Extension, Colorado State Univ., Ft. Collins, July 2008.

Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: Nitrate-N concentrations exceeding the Water Drinking Standard of 10 ppm were reported in the Arkansas River Valley of southeastern Colorado. There is also evidence of high NO3-N concentrations in the soils of intensively cropped fields and the potential for their leaching below the root zone. This potential is exacerbated by inefficient irrigation since the majority of cropland in the Arkansas Valley is furrow-irrigated. A field experiment was conducted at the Arkansas Valley Research Center in 2007 to test the residual effects of two years (2005 and 2006) of manure application (10, 20, and 30 tons/acre) and N fertilizer (60, 120, and 180 lb N/acre) on corn yield, N and P uptake, and soil N03-N and P concentrations with subsurface drip irrigation (SDI) and furrow irrigation (FrI). There were no significant differences in corn yield between SDI and FrI in 2005, 2006, and 2007, even though, on average, 43% more water was applied with FrI than with SDI. The highest corn yields were obtained with 180 lb N/acre in 2005 and with as little as 60 lb N/acre or 10 tons of manure/acre in 2006. With no N fertilizer or manure applied in 2007, the manure and high N rate treatments produced an average of 224 bu/acre of corn. At the end of 2007, there was enough residual soil N left in the high manure treatment to produce top corn yields for two years. Soil P test levels in the 20 and 20 tons/acre manure treatments exceeded P sufficiency levels in all three years. The elevated NO3-N and P levels in the soil led to increased N and P uptake by the corn grain in 2006 and 2007. Applying manure in excess of crop nutrient requirements can lead to N and P buildup in the soil and associated water pollution hazards, as demonstrated in this study. An informal survey revealed that manure application rates in the Arkansas Valley ranged from less than 10 to over 40 tons/acre, with rates around 20 tons/acre being common. PARTICIPANTS: Individuals who contributed to this project include Ardell Halvorson of USDA-ARS in Fort Collins, CO and Michael Bartolo, Kevin Tanabe, and James Valliant of Colorado State University. The project results were exhibited at a July 2007 field day at the Arkansas Valley Research Center. TARGET AUDIENCES: The target audience for this project includes growers, consultants, extension agents, and NRCS personnel in the Arkansas River Valley of southeastern Colorado. PROJECT MODIFICATIONS: None

Impacts
This study demonstrated the feasibility of sub-surface drip irrigation (SDI) as an alternative to furrow irrigation for corn production in the Arkansas Valley. On average, 43% water can be saved by switching to SDI. Further savings can be achieved with sound irrigation scheduling. It also confirmed previous research results that N fertilizer rates in the Arkansas Valley can be reduced substantially without impacting corn yield. Manure rates in excess of crop nutrient requirements can lead to N and P buildup in the soil.

Publications

• Berrada, A., Halvorson, A.D., Bartolo, M.E., and Valliant, J. 2007. The effects of drip irrigation and fertilizer rate on corn yield and soil salinity in the Arkansas River Valley. p. 6-12 In Agric. Exp. Sta. Tech. Rep. TR07-14, Colorado State Univ., Ft. Collins, CO.
• Halvorson, A.D., Bartolo, M.E., Reule, C.A., and Berrada, A.. 2007. Onion response to nitrogen fertilization under drip and furrow irrigation. p. 49-53 In Agric. Exp. Sta. Tech. Rep. TR07-14, Colorado State Univ., Ft. Collins, CO.
• Berrada, A. 2007. The effects of drip irrigation on corn yield and soil salinity in the Arkansas Valley. From the Ground Up Agronomy News, 26 (1): 12-13. Cooperative Extension, Colorado State Univ., Ft. Collins, April 2007.
• Berrada, A. 2007. The effects of manure and N rates on corn yield and nutrient balance under drip and furrow irrigation. Abstracts, Amer. Soc. of Agron., Madison, WI. (CD-ROM). ASA-CSSA-SSSA International Annual Meetings, November 4-8, 2007, New Orleans, LA.

Progress 01/01/06 to 12/31/06

Outputs
Most cropland in the Arkansas River Valley of southeastern Colorado is furrow-irrigated, but drip irrigation is gaining in importance due to diminishing water supplies and other considerations. A field trial was conducted at the Arkansas Valley Research Center (AVRC) in 2005 and 2006 to determine the effects of irrigation type, irrigation scheduling, and fertilizer rates on corn yield, N dynamics, and salt accumulation in the rootzone. Four N fertilizer rates (0, 67, 134, and 201 kg N/ha) and four manure rates (22, 44, and 68 Mg/ha) were compared using subsurface drip irrigation (SDI) and furrow irrigation (FrI) under full- and deficit-irrigation regimes. Drip tapes were placed 20 cm below the soil surface at 152-cm lateral spacing. There were no significant differences in grain yield between SDI and FrI in 2005 and 2006, even though 76% more water was applied with FrI in 2005 and 57% in 2006. Deficit irrigation decreased corn yield significantly in 2005 but not in 2006 due to more rainfall in 2006. Optimum yields were obtained with approximately 67 kg N/ha and 22 Mg of manure/ha in both years, while 68 Mg manure/ha depressed corn yield, particularly with SDI and deficit irrigation. Manure application increased soil salinity early in the season, which led to significantly lower plant populations with 44 and 68 Mg/ha in 2005 and 68 Mg/ha in 2006. Some salt accumulation was observed at the 1.2- to 1.8-m soil depth under SDI compared to FrI in the fall of 2005. There was also more residual soil nitrate-N under SDI at 201 kg N/ha and 22 and 44 Mg manure/ha in the fall of 2005 but not in the spring of 2006. Other studies conducted at AVRC in 2006 include several crop variety (hybrid) performance trials. Good to excellent seed and forage yields were observed in 2006 due to above-average precipitation, with the exception of winter wheat, which suffered from severe lodging late in the season. All the crops tested (alfalfa, Nuna bean, grain corn, corn silage, forage sorghum, winter canola, and winter wheat) were furrow-irrigated. Partial results are available at: http://www.colostate.edu/Depts/SoilCrop/extension/CropVar/index.html.

Impacts
The irrigation system by fertilizer rate study indicates that corn can be grown successfully with drip irrigation in the Arkansas River Valley. Drip irrigation would save substantial amounts of water, which could be used to irrigate more land or higher-value crops such as onions and cantaloupes. These and other vegetable crops are increasingly irrigated with SDI and are often grown in rotation with corn. Some of the challenges of drip irrigation in the Arkansas Valley are (1) getting enough water to the seedbed to ensure adequate seed germination and plant establishment, and (2) managing excess salts, particularly if well water is the irrigation water source since it generally contains a higher salt concentration than surface water. Top corn yields were obtained with as little as 67 kg N/ha or 22 Mg manure/ha; thus the potential exists for enhancing N fertilizer use efficiency and minimizing leaching of nitrate-N in the Arkansas Valley. The results of the crop variety performance trials are used by Arkansas Valley growers to select adapted varieties and hybrids.

Publications

• Berrada, A., Halvorson, A.D., Bartolo, M.E., Valliant, J. 2006. The effects of subsurface drip and furrow irrigation on the movement of salts and nitrate in the root zone. p. 1-13 In Proceedings of the 27th International Irrigation Show, 5-7 Nov. 2006, San Antonio, TX. The Irrigation Association.
• Berrada, A., Johnson, J.J. 2006. Irrigated winter wheat planting date study at Rocky Ford in 2005. p.29-31 In J.J. Johnson (ed.) Making Better Decisions: 2005 Colorado Winter Wheat Variety Performance Trials. Agric. Exp. Sta. Tech. Rep. TR06-09, Colorado State Univ., Ft. Collins, CO. Contributed to several other crop testing publications in Colorado.
• Halvorson, D., Bartolo, M.E., Reule, C.R., Berrada, A. 2006. Onion response to nitrogen fertilization under drip and furrow irrigation. p. 7-12 In A.J. Schelegel (ed.) Great Plains Soil Fertility Conference Proceedings, vol. 11, March 7-8, 2006, Denver, CO.
• Halvorson, A.D., Bartolo, M., Reule, C.A., Berrada, A. 2006. Onion Response to mitrogen fertilization under drip and furrow irrigation. Proceedings National Allium Research Conference. December 7-8, 2006, College Station, TX p. 73-78.
• Halvorson, A.D., Bartolo, M., Reule, C.A., Berrada, A. 2006. Drip versus furrow irrigation for onion production in the Colorado Lower Arkansas River Valley. Soil and Water Conservation Society. Abstract. July 22-26-2006, Keystone, CO. J. Soil and Water Conserv. 61(3):229.
• Larson, K.J., Berrada, A., Thompson, D.L. 2006. Sorghum hybrid performance trials in Colorado, 2005. Agric. Exp. Sta. Tech. Rep. TR06-04, Colorado State Univ., Ft. Collins, CO.
• Berrada, A., Halvorson, A.D., Bartolo, M.E., Valliant, J. 2006. The effect of manure and N rates on corn yield and salt and nitrate movement in the soil under furrow and drip irrigation in the Arkansas River Valley. p. 264-269 In A.J. Schelegel (ed.) Great Plains Soil Fertility Conference Proceedings, vol. 11, March 7-8, 2006, Denver, CO.

Progress 01/01/05 to 12/31/05

Outputs
Alfalfa is an important crop in Colorado in general and southwestern Colorado in particular. With recent droughts and high fertilizer costs, Colorado producers are looking for ways to optimize water and fertilizer use. A study was conducted in 1995-2000 to determine the effects of four initial (pre-sowing) P (0, 37, 74, and 148 kg/ha) by three K (0, 93, and 186 kg/ha) fertilizer application rates on soil and plant P and K concentrations and alfalfa DM production in a calcareous soil. In addition, 37 kg P/ha were applied annually to half of each plot in the spring of 1997, 1998, and 1999. Potassium fertilization increased alfalfa dry matter (DM) yield significantly in 1996 only. Soil test K level was not impacted by K fertilization and remained above the critical level throughout the duration of the study. The initial P application did not affect alfalfa DM production significantly in 1996, 1997, 1998, and in total from 1996 through 1999. Conversely, the annual application of 37 kg P /ha increased alfalfa DM by a total of 3.2 Mg/ha in 1997 through 1999, when no P was applied initially. The initial and annual P fertilizer applications increased alfalfa P and soil AB-DTPA P concentrations significantly in 1997-1999 and 1998-2000, respectively. When no P was applied, soil test P level at the 0- to 15-cm depth dropped from 8.3 mg/kg at the initiation of the study in Aug. 1995 to less than 1.0 mg/kg at study termination in Apr. 2000. Alfalfa yield response to P fertilizer was small even when soil test P level dropped to well below the critical level. No yield advantage was observed to maintaining soil test P above the critical level. A second study was conducted in 2002 and 2003 to evaluate the effect of water stress on alfalfa DM production and hay quality, using subsurface drip irrigation (SDI). Drip tapes were placed 45 cm below ground, at 152-cm lateral spacing. Low, moderate, and severe water stresses were imposed on three alfalfa cultivars with contrasting dormancy rating. In the least stressed treatment, soil water content in the root zone (0 to 1.8 m) was maintained at approximately 50 % of available water capacity (AWC) throughout each growth period. In the moderate and severe stress treatments, soil water content was maintained at 50% AWC during the first two weeks of each growth period and at either 25% AWC (moderate) or 10% AWC (severe) thereafter. Alfalfa DM production averaged 12.8 Mg/ha in 2002 and 11.9 Mg/ha in 2003, with no significant differences among cultivars. It increased significantly with increasing amounts of irrigation. Alfalfa protein concentration averaged 21% in 2002 and 2003, with no significant differences among cultivars or irrigation treatments. Alfalfa relative feed value (RFV) was highest in the most stressed treatment and lowest in the least stressed treatment. It took 12.6 cm of water to produce 1.0 Mg of alfalfa hay in the least stressed treatment and 14.3 cm in the most stressed one. Visual observations indicate that 102-cm lateral spacing would be more suitable than 152-cm spacing. It would eliminate dips (low-growth middle area between tapes) in alfalfa growth by providing a more uniform water distribution.

Impacts
Based on these and other research results, a response to K fertilization is unlikely on most alfalfa producing soils in Colorado, due to their high K buffering capacity. Our results suggest that annual P fertilizer application is superior to one-time application for irrigated alfalfa production on calcareous soils. Subsurface drip irrigation (SDI) produced comparable alfalfa hay yields to sprinkler irrigation. Drip tape lateral spacing of approximately 100 cm would ensure uniform water distribution and maximize hay production. Installation cost, maintenance requirements, and gopher control are some of the challenges that could impede the adoption of SDI by alfalfa hay producers in southwestern Colorado.

Publications

• Berrada, A., and Westfall, D.G. 2005. Irrigated Alfalfa Response to Phosphorus and Potassium in a Calcareous Soil. Communications in Soil Science and Plant Analysis, 36: 1213-1227.
• Berrada, A. 2005. Alfalfa Response to Water Deficit Using Subsurface Drip Irrigation. Agric. Exp. Stn. Tech. Bull. TB05-01, Colorado State Univ., Ft. Collins, CO.

Progress 01/01/04 to 12/31/04

Outputs
A study was conducted in 2000 to 2004 to assess the feasibility of dryland cropping systems in southwestern Colorado and southeastern Utah. Precipitation was below normal every year of the study, except in 2004. Winter wheat after a 14-month fallow period produced the best seed yield in the driest years, 2000 and 2002, compared to more intensive crop rotations. This was due to more available soil moisture at planting, particularly with minimum- or no-till practices and adequate nitrogen fertilization. In years with timely precipitation, cropping systems which produced one crop per year or two crops per three years generally outperformed winter wheat-fallow. Examples are: winter wheat-bean in 2003 and winter wheat-corn-bean in 2003 and 2004. Corn appears to be a good crop in rotation with winter wheat and dry bean in southwestern Colorado, for unknown reasons. In general, spring crops performed poorly due to dry conditions in May, June, and July. Safflower depleted soil moisture more than corn or pinto beans. Our data suggest that winter wheat-safflower-fallow is preferable to winter wheat-safflower-bean in the project area. Chickpea did not do as well as expected in rotation with winter wheat. It was hypothesized that by planting and harvesting chickpeas early compared to pinto beans, winter wheat could be planted at a more optimum date after chickpeas than after pinto beans. Often chickpea seed maturity was delayed by frequent rain events in August or September, resulting in late harvest and poor seed quality. Chickpea showed promise in other trials but more research is needed to develop cultivars and management practices that are best suited to the environment of southwestern Colorado. Other crops should be tested as well to diversify production, with particular emphasis on meeting the demands of niche markets. Organic chickpea production appears to be profitable in southwestern Colorado.

Impacts
This study shows that minimum and no-till management practices can save valuable soil moisture in dry years. They will also curtail soil erosion which is a big concern in southwestern Colorado. The results also point to potential benefits of crop diversification and the need for long-duration research on cropping systems.

Publications

• Berrada, A. 2004. Developing Sustainable Dryland Cropping Systems in SW Colorado and SE Utah Using Conservation Tillage and Crop Diversification: 2002 and 2003 Results. Agric. Exp. Sta. Tech. Rep. TR04-02, Colorado State Univ., Ft. Collins, CO.
• Berrada, A. 2004. Results of Chickpea Research in Southwestern Colorado from 1994 to 2003. Agric. Exp. Sta. Tech. Rep. TR04-03, Colorado State Univ., Ft. Collins, CO.
• Berrada, A. 2004. Results of the Irrigated Winter Triticale at Yellow Jacket 1996-1999. p. 95-100 In J.E. Brummer and C.H. Pearson (ed.) Colorado Forage Research 2003: Alfalfa, Irrigated Pastures, and Mountain Meadows. Agric. Exp. Sta. and Coop. Ext. Tech. Rep. TR04-01, Colorado State Univ., Ft. Collins, CO.
• Berrada, A., and Brummer, J.E. 2004. Evaluation of Spring Cereals for Dual Use. p. 101-106 In J.E. Brummer and C.H. Pearson (ed.) Colorado Forage Research 2003: Alfalfa, Irrigated Pastures, and Mountain Meadows. Agric. Exp. Sta. and Coop. Ext. Tech. Rep. TR04-01, Colorado State Univ., Ft. Collins, CO.

Progress 01/01/03 to 12/31/03

Outputs
The recent drought and expanding alfalfa acreage in southwestern Colorado under the Dolores Irrigation Project resulted in high water usage in 2000 and 2001 and water shortages in 2002 and 2003. Only about 28% of the normal water allotment (1430 mm ha-1) in 2002 and 60% in 2003 was delivered to Full Service (FS) irrigators. This raised concerns about the long-term feasibility of the Dolores Project and emphasized the need for research and education to enhance water conservation and management in southwestern Colorado. In this context, a field experiment was conducted in 2002 and 2003 to investigate the effect of water stress on alfalfa dry matter (DM) yield and hay quality. Three irrigation treatments (full irrigation and moderate and severe water stress) were imposed on three alfalfa cultivars with contrasting dormancy rating in a split-block design. The irrigation system used was subsurface drip irrigation (SDI) with 152.4 cm lateral spacing and 41 to 46 cm placement depth. Total alfalfa DM production (adjusted to 12% moisture) averaged 9.5 tons per hectare in 2003, with no significant differences among cultivars. Irrigation treatment had a pronounced effect on alfalfa DM production, regardless of the cultivar. The non-stressed treatment produced the highest DM yield (11.6 t/ha), while the moderately and severely stressed treatments produced 10.0 and 6.8 t/ ha, respectively. Alfalfa production in 2003 was negatively impacted by a hailstorm, which occurred on 9 September. Alfalfa protein concentration averaged 21% with no significant differences among cultivars or irrigation treatments. Alfalfa relative feed value (RFV) increased as water stress intensity increased. Comparable results were obtained in 2002, although DM yield and RFV were higher in 2002 than in 2003. Overall, alfalfa DM yield increased linearly (R2 = 0.8) with increasing irrigation amount. The reverse was true vis-a-vis RFV. Alfalfa water use efficiency averaged 8.0, 8.3, and 7.1 kg of DM per mm of water (precipitation + irrigation + change in soil water) with the non-stressed, the moderately stressed, and the severely stressed treatment in 2003, respectively. Soil moisture was not monitored in 2002. Alfalfa DM production of 9.0 to 11.0 t/ha is achievable in the FS area of the Dolores Project. Current long-term average is closer to 7.1 t/ha. Water usage in the FS area averaged 1,489 mm per irrigated hectare of alfalfa in 1995 to 2001. This translates into an irrigation water use efficiency of 4.8 kg/mm. Total water use efficiency would be even lower, 3.8 to 4.0 kg/mm. This reflects the low efficiency of the predominant irrigation system (sideroll) in the FS area compared to SDI and the low alfalfa yield.

Impacts
Subsurface drip irrigation is not expected to replace sprinkler irrigation in the Dolores Project anytime soon, due to its high initial cost, high maintenance, and high management skill requirement. It does however show that vast improvements in water use efficiency in the Dolores Project are possible. More research is needed to refine SDI design and develop best management practices for crop production under the Dolores Project. Furthermore, strategies need to be developed to address water shortages.

Publications

• Berrada, A. 2003. Water management for optimum crop production in SW Coloado. Agron. Abstracts, Amer. Soc. of Agron., Madison, WI. (on CD-ROM).

Progress 01/01/02 to 12/31/02

Outputs
A major challenge for crop production in southwestern Colorado and southeastern Utah is water availability. This was abundantly clear in 2002 due to a severe drought, following two years of below average precipitation. Total precipitation at Yellow Jacket, CO in 2002 was 217 mm, or 54 % of normal. It was even less (39 % of normal) during the crop season (Oct. 2001 to Sep. 2002). The cumulative effect of the 3-yr. drought severely impacted crop production in southwestern Colorado and southeastern Utah. In a dryland cropping systems research study, winter wheat averaged 838 kg/ha at Yellow Jacket, CO; 575 kg/ ha at Eastland, UT; and less than 200 kg/ha at Goodman Point, CO. Winter wheat after a 13-month fallow season produced significantly more grain at two locations than winter wheat after spring grains (oat, safflower, chickpea, pinto bean, or corn). This was due to more available soil moisture and earlier seeding after fallow than after spring grains. There was also a significant advantage of minimum tillage over conventional tillage in the wheat-fallow rotation at one location in 2002. The 2000 to 2002 results indicate that growing one crop each year in the semi-arid environment of southwestern Colorado and southeastern Utah may not be feasible in the long term. Two-to four-year crop rotations with one fallow year would be more sustainable. Irrigated crop production was also severely impacted by limited water supplies in 2002. Full service irrigators in the Dolores project were allotted 28% of their normal water allocation of 1,411 mm/ha. This was barely enough to produce one cutting of alfalfa hay. Alfalfa dry matter production was strongly correlated to irrigation depth at Yellow Jacket in 2002. It took 137 mm of water (precipitation + storage) on average to produce 2.2 Mg/ha of alfalfa hay, using subsurface drip irrigation. Substantially more water would have been required to produce the same amount of hay if a sprinkler irrigation system had been used in 2002.

Impacts
Subsurface drip irrigation has the potential of enhancing irrigation water management in southwestern Colorado, but its use will depend largely on economic and practical considerations.

Publications

• Berrada, A., Peterson, G.A., Ayers, P.D., Hooten, T.M., Hammon, R.W., Sharp, R.L., and Skouson, J. 2002. Developing Sustainable Dryland Cropping Systems in SW Colorado and SE Utah Using Conservation Tillage and Crop Diversification: 2000 & 2001 Results. Agric. Exp. Stn. Tech. Bull. TB02-2, Colorado State Univ., Ft. Collins, CO.
• Berrada, A. 2002. An In-Depth Look at Cropping Systems in SW Colorado and SE Utah. Agron. Abstracts, Amer. Soc. of Agron., Madison, WI.

Progress 01/01/01 to 12/31/01

Outputs
The conversion of dryland farms to irrigated in the Dolores Project area is fairly recent (1987-present) and there are plans to irrigate additional land in the future. Thus the importance of generating information to assist farmers to manage their water allotment efficiently. The amount of water used per irrigated acre exceeded the allocated amount in 6 out of 10 years in the Full Service Area (FSA). The anticipated system capacity of 0.211 ha m was based on a water delivery efficiency of 87% and an 'ideal' crop rotation of 55% alfalfa, 20% small grains, 15% dry bean, 3% pasture, and 7% corn. Water delivery efficiency has been exceeded (95% versus 87%), in effect raising water allotment to 0.232 ha m. The land in irrigated alfalfa has been much higher than anticipated (90% in 2000) which may explain in part the high water usage during dry years. A study was initiated in 1996 and completed in 2001 to (1) assess irrigation water management in the FSA, (2) demonstrate the use of the Watermark moisture sensor and ETgage atmometer for irrigation scheduling purposes, and (3) initiate research and education programs to address specific constraints. A survey conducted in the fall of 1996 identified concerns relating to irrigation system design at the farm level, runoff, and irrigation scheduling. Watermark sensors were used to monitor soil moisture in 25 irrigated fields in 1997 through 1999. ETgage atmometers were used to monitor crop evapotranspiration (ET) at five locations. Irrigation and rainfall amounts were measured with rain gauges. ET based water balance tables were constructed for each alfalfa field and year. Generally, the water balance was positive to near zero at the first alfalfa cutting and negative at the second and third cuttings. There was good to partial agreement between the Watermark sensor readings and water balance computations in 11 out of 17 alfalfa field by year sites. Where there were large discrepancies between the two methods, Watermark sensor readings appeared to better reflect water availability to the crop than did water balance computations. Water supply in most fields was not enough to keep up with crop ET and maintain adequate soil moisture. A strong correlation was found between the Watermark sensor Model 200SS readings and water content of the predominant soil type in the FSA. A third degree polynomial provided an excellent fit for the data. Slow Watermark response to soil drying was observed at readings of approximately 0 to 10 kPa and above 150 kPa. Close agreement between alfalfa reference evapotranspiration (ETr) values measured with ETgage Model A or computed using the 1982 Kimberly-Penman equation was achieved during the growing season (May to September). The highest correlation was obtained when ETr values were averaged over three and seven-day periods.

Impacts
Several well attended workshops and field days were generated as a result of this study, which could serve as the basis for implementing a water management assistance program in the Dolores Irrigation Project. Follow up research is being conducted to determine the effects of limited water supplies on alfalfa hay production and quality as well as develop best management strategies to address water shortages.

Publications

• Berrada, A., Stack, M.W., and Cardon, G.E. 2001. Assessment of Irrigation Water Management and Demonstration of Irrigation Scheduling Tools in the Full Service Area of the Dolores Project: 1996-2000. Part I: Survey Results. Colorado Agricultural Experiment Station Technical Report Series, TR01-6, Colorado State Univ., Ft. Collins, CO.
• Berrada, A., Hooten, T.M., and Broner, I. 2001. Assessment of Irrigation Water Management and Demonstration of Irrigation Scheduling Tools in the Full Service Area of the Dolores Project: 1996-2000. Part II: Calibration of the Watermark Soil Moisture Sensor and ETgage Atmometer. Colorado Agricultural Experiment Station Technical Report Series, TR01-7, Colorado State Univ., Ft. Collins, CO.
• Berrada, A., Hooten, T.M., Broner, I., and Cardon, G.E. 2001. Assessment of Irrigation Water Management and Demonstration of Irrigation Scheduling Tools in the Full Service Area of the Dolores Project: 1996-2000. Part III: Monitoring of Irrigated Alfalfa Fields Using the Watermark Moisture Sensor and ETgage Atmometer. Colorado Agricultural Experiment Station Technical Report Series, TR01-8, Colorado State Univ., Ft. Collins, CO.

Progress 01/01/00 to 12/31/00

Outputs
This was the first year of a three-year western SARE project titled `Developing Sustainable Dryland Cropping Systems in SW Colorado and SE Utah Using Conservation Tillage and Crop Diversification'. The main purpose of this project is to evaluate cropping systems that would maximize water (from rain and snow) use efficiency and economic return and minimize the detrimental effects to the environment, i.e., due to soil erosion. Three field trials were established in the fall of 1999 and spring of 2000 at the Southwestern Colorado Research Center and Goodman Point in Montezuma County, CO and near Eastland in San Juan County, UT. Treatments vary among sites but include at least one cropping system that is common to the area. A severe drought during most of the 1999-00 season (October-September) resulted in partial or total crop failure. Total precipitation from October 1999 through September 2000 at the Research Center averaged 213 mm compared to a 30-year average of 404 mm. Only winter wheat after summer fallow produced near average seed yield. A spring application of 44.8 kg ha-1 of N at the Eastland site caused a significant increase in wheat yield (1940 vs. 1565 kg ha-1 for the control). Wheat protein content was not affected by N application. At the Research Center, winter wheat yield was significantly higher after summer fallow than after spring crops. The lowest yield was obtained after chickpea, probably due to extensive soil moisture extraction by chickpea as compared to pinto bean, which has a shallower root system. The combination of severe drought and low soil moisture content at planting contributed to extremely low pinto bean and chickpea yield at Goodman Point. The plot area had been in alfalfa for seven years until late summer 1999 when alfalfa was killed using a Noble blade implement. We hypothesize that alfalfa, because of its taproot system, used most of the available soil moisture prior to its termination in 1999. The fall of 1999 was extremely dry, as were the months of December, February, and April, allowing for very little recharge of the root zone prior to the planting of pinto beans and chickpeas on May 18, 2000. Additional stress may have resulted from too much residual N, which could have favored vegetative growth at the expense of seed production.

Impacts
It is too early to make recommendations or assess the impact of this project on agriculture in the Four Corners area. Potential benefits include increased water use efficiency due to intensive crop rotations, reduced erosion due to less soil disturbance (minimum tillage), and reduced financial risk due to more crop diversification than has been the case. Farmers' participation in the field trials was excellent.

Publications

• Berrada, A., and Peterson, G.A. 2000. Development of Sustainable Dryland Cropping Systems in SW Colorado and SE Utah. Agron. Abs. p. 132, Amer. Soc. of Agron., Madison, WI.

Progress 01/01/99 to 12/31/99

Outputs
Over 80% of the irrigated acreage in Dolores and Montezuma Counties are in alfalfa. There is a wide variation in the amount of phosphorus (P) and potassium (K) recommended for optimum alfalfa hay production. Most soils in southwestern Colorado test in the low (0-3 ppm) to medium range (4-7 ppm) for P and in the high range for K (>120 ppm) based on AB-DTPA test. A field experiment was initiated in 1995 at the Southwestern Colorado Research Center to determine the response of irrigated alfalfa to P and K rates and assess P and K maintenance rates. Four rates of P (0, 37, 74, and 148 kg/ha) and three rates of K (0, 93, and 186 kg/ha) were applied in the fall of 1995 as factorial treatments in a randomized complete block design with four replications. An additional 37 kg/ha of P was applied to half of each plot in the spring of 1997,1998, and 1999. Initial soil test results were pH - 7.7, O.M. - 1.0%, AB-DTPA P - 5.2 ppm (0-30cm), and K - 150 ppm (0-30cm). The Colorado State University 3-year recommendation would have been 74 kg/ha of P and no K fertilizer. Each plot was harvested twice in 1996 and 1999, and three times in 1997 and 1998. Alfalfa dry matter (DM) was determined for each cutting and each plot in all years, and in 1997 through 1999, alfalfa P and K concentration was also measured. Soil P and K concentration was measured in 1998 and 1999 from selected treatments. Data from this study show that: alfalfa DM increased significantly in 1996 with 93 kg/ha of K. There was no significant response in subsequent years although higher K concentration was observed in 1997 with 186 kg/ha of K compared to the untreated check. Alfalfa DM did not respond to an initial application of up to 148 kg/ha of P except in 1999. Alfalfa P concentration was, however, significantly impacted by P fertilizer rate in 1997 and 1998. The addition of 37 kg/ha of P in the spring of 1997 through 1999 maintained soil P level in the medium range for fertilizer recommendation. It also significantly increased alfalfa P concentration in 1997 and DM in 1998 and 1999 in the initial zero and low P fertilizer treatments. The P x K interaction on alfalfa P concentration or DM was not significant at alpha=0.05.

Impacts
Based on the resuts of this study and numerous soil test results, it appears that K is not a limiting factor to alfalfa hay production in southwestern Colorado. Further data analysis should help determine P and K required to maintain soil test levels above the threshold at which a response to P or K would be expected.

Publications

• Berrada, A., Westfall, D.G., Stack, M.W., and Hooten, T.M. 1999. Response of irrigated alfalfa to P and K rates. Agron. Abs. p. 245 Amer. Soc. of Agron., Madison, WI.
• Al-Kaisi, Mahdi M., Berrada, Abdel F., and Stack, Mark W. 1999. Dry bean yield response to different irrigation rates in southwestern Colorado. J. Prod. Agric. 12:422-427
• Berrada, A., Stack, Mark W., Riddell, Bruce, Brick, Mark A., and Johnson, Duane L. 1999. Chickpea: A Potential Crop for Southwestern Colorado. p. 206-213 In Jules Janick (ed). Perspectives on New Crops and New Uses, ASHS Press, Alexandria, VA. Proceedings of the Fourth National Symposium `New Crops and New Uses Biodiversity and Agricultural Sustainability', Phoenix, Arizona, November 8-11, 1998.
• Hammon, R.W., Sanford, D.V., Stack, M.W., Berrada, A., and Peairs, F.B. 1999. Dryland winter wheat planting date and Russian wheat aphid studies in southwestern Colorado, 1990-1998. Tech. Rep. TR 99-2. Colorado State Univ., Ag. Exp. Stn., Dept. of Bioagric. Sci. and Pest Management, Southwestern Colorado Research Center, Fruita Research Center
• Berrada, A., Cardon, G.E., Broner, I., Hooten, T.M., and Stack, M.W. 1999. Evaluation of irrigation water management in southwestern Colorado. Agron. Abs. p. 278, Amer. Soc. of Agron., Madison, WI.

Progress 01/01/98 to 12/31/98

Outputs
Southwestern Colorado is traditionally a dryland dry bean production area but the combination of low yields and declining prices has led to a substantial reduction in dry bean acreage in the last four years. There is a need to diversify dryland cropping systems in southwestern Colorado to minimize risks. Field studies have been conducted at the Southwestern Colorado Research Center since 1994 to evaluate chickpea (Cicer arietinum L.) as an alternative to dry bean. The results show good yield potential and adaptability of several cultivars. Average chickpea yields of 1000 to 1700 kg/ha were achieved under dryland conditions at Yellow Jacket, CO in 1995, 1997, and 1998. In comparison, Montezuma county dry bean yield ranged from a low of 325 kg/ha in 1995 to a high of 784 kg/ha in 1997. Cultivar and planting date had a significant effect on chickpea seed size and yield in 1997 and 1998. 'UC27' had the highest seed yield in both years followed by 'Dwelley' in 1997. Acceptable seed quality for canning was produced by 'UC27' and 'Dwelley' and for dry packaging by 'Sanford' and 'Evans'. Optimum planting date appears to be around 21 May at Yellow Jacket. Irrigation water and/or N fertilization increased chickpea seed yield significantly in 1994-1996. 'Sanford' seed yields of 2500 to 2700 kg/ha were produced with 56 kg N/ha and approximately 28 cm of precipitation (irrigation plus rainfall). Chickpea and dry bean can be grown and processed using similar equipment and management practices. Chickpea is more frost tolerant than dry bean and can be planted and harvested few weeks earlier, allowing for a more optimum planting date of winter wheat. Southwestern Colorado is well suited to dry packers and canners. The freight availability may create some problems in timely deliveries and transportation expenses. Good chickpea seed quality has been produced in southwestern Colorado but late planting and/or frequent rains can delay maturity and increase the incidence of stained seeds. More research is needed to identify cultivars and management practices that will enhance the marketability of chickpea produced in southwestern Colorado.

Impacts
(N/A)

Publications

• BRICK, M.A., BERRADA, A., SCHWARTZ, H. F., and KRALL, J. 1998. Garbanzo bean production trials in Colorado and Wyoming. Colorado and Wyoming Agric. Exp. Stn. Tech. Bull. TB 98-2, Colorado State Univ. and Univ. of Wyoming.
• BERRADA, A., SANFORD, D.V., and STACK, M.W. 1998. Garbanzo bean yield and adaptation trials at Yellow Jacket, CO. p. 14-22. In M.A. Brick, A. Berrada, H. Schwartz, and J. Krall (ed.) Garbanzo Bean Production Trials In Colorado and Wyoming. Colorado and Wyoming Agric. Exp. Stn. Tech. Bull. TB 98-2, Colorado State Univ. and Univ. of Wyoming.

Progress 01/01/97 to 12/31/97

Outputs
The conversion of dryland farms to irrigation in the Dolores Project area is fairly recent (1987-Present). In 1987, only 1,169 acres were irrigated in the full service area (FSA) and in 1996, approximately 86% of the allocated acres (28,000) was in production. The amount of water used per irrigated acre exceeded the allocated amount in 6 out of 10 years. The anticipated system capacity of 20.5 inches per acre was based on a water delivery efficiency of 87% and an 'ideal' crop rotation of 55% alfalfa, 20% small grains, 15% dry bean, 3% pasture, and 7% corn. While water delivery efficiency has been exceeded, the acreage in alfalfa has been much higher than anticipated (70 to 80%) which may explain in part the high water usage during dry years. Poor management is also to blame. A questionnaire was sent to 178 farmers -of which 95 were farm operators, in the fall of 1996 to assess irrigation management in the Full Service Area (FSA) of the Dolores Water Project. Forty-two completed questionnaires were returned. In addition, 13 fields were monitored during the 1997 irrigation season to gain a better understanding of the issues identified in the survey. The majority (88%) of the respondents used siderolls to irrigate their land while 44% used siderolls and/or center pivots. Forty-two per cent of the respondents reported using 6 gpm or smaller nozzles on some of their systems while 22% reported using 9 gpm or larger nozzles. The smaller nozzles approximate the Dolores Project pumping capacity (5.8 gpm during peak usage) while larger nozzles may result in deep percolation or runoff if not carefully monitored. Sixty-two percent of the respondents reported irrigation water runoff from their fields while 36% reported no runoff. Fifty-two per cent of the respondents based their decision on when to irrigate by checking soil moisture with a shovel or soil probe. However, 45% reported that they continuously moved their siderolls regardless of soil moisture content and/or crop water use. Most of the respondents expressed the need for timely information on crop water use and irrigation scheduling. Earlier studies at the southwestern Colorado Research Center revealed the need to develop crop coefficients that more closely reflect the climatic conditions in southwestern Colorado than those used in existing irrigation scheduling programs. It is important that local environment be considered in any adaptation or transfer of water management programs. Several tools for improving irrigation management in the Dolores Project Area were demonstrated during the well-attended August '97 field day at the research center. More research and outreach activities are scheduled for 1998 to help irrigators in the Dolores Project area manage their water allocation efficiently.

Impacts
(N/A)

Publications

• AL KAISI, MAHDI M., BERRADA, ABDEL, AND STACK, MARK. 1997. Evaluation of irrigation scheduling program and spring wheat yield response in southwestern Colorado. Agric. Water Management 34 (1997) 137-148. Elsevier Science Inc.
• BERRADA, ABDEL. 1997. Highlights of Irrigation Management Survey in the Full Service Area of the Dolores Irrigation Project. Ag Research News, p. 1B In the Montezuma Valley Journal, Sept. 27, 1997.
• BERRADA, A. WESTFALL, D.G., SANFORD, D.V., AND STACK, M.W. 1997. Irrigated Alfalfa Response to P and K in Southwestern Colorado. Agron. Abstracts p. 230, Amer. Soc. of Agron., Madison, WI.

Progress 01/01/96 to 12/30/96

Outputs
The 1995-96 season was one of the driest on record in southwestern Colorado. A total of 22 cm of precipitation was recorded at Yellow Jacket, CO from October 1995 through September 1996, compared to a 30-year average of 40 cm. Consequently, dryland winter wheat and dry bean yields were extremely low averaging less than 1000 kg/ha and 200 kg/ha, respectively. Russian wheat aphid (RWA) infestation was very high, causing substantial yield reductions in untreated wheat. The seed treatment Gaucho 480 FS (imidacloprid) at 250 mg a.i./100 kg was effective in controlling RWA in irrigated spring wheat. The treated plots averaged 1.2 RWA per infested tiller while the untreated plots averaged 6.1 RWA per infested tiller. Grain yield was 6,345 kg/ha in the treated plots and 4,807 kg/ha in the untreated ones. Gaucho was also effective in controlling RWA in 'Fairview' hard red winter wheat under dryland conditions but not under irrigation. Several advanced lines from the dry bean breeding program at Fort Collins, CO were tested at Yellow Jacket, to identify pinto bean varieties with high yield potential and disease resistance. The yields were somewhat disappointing since they only averaged 1651 kg/ha but a few lines exhibited desirable characteristics which will be investigated further. Much higher pinto bean (var. 'Bill Z') yields, 3,255 kg/ha on the average, were obtained in the irrigation by N rate experiment. There were no significant differences among N rates (0 to 112 kg N/ha in 28 kg/ha increments).

Impacts
(N/A)

Publications

• STACK, M. W., BERRADA, A., and SANFORD, D.V. 1996. Effects of Seeding Date, Seeding Rate, and Seed Treatment on Irrigated Winter Wheat. Agron. Abstracts p. 116, Amer. Soc. of Agron., Madison, WI.
• SANFORD, D.V. 1996. Salt Tolerant Forages. p. 5 In District Directions, The Dolores Soil Conservation District, Cortez, CO 81321.
• BERRADA, A., and SANFORD, D.V. 1996. Garbanzo bean test seems to offer alternative to pintos. p. 5 In Dove Creek Press, March 28, 1996.
• BERRADA, A., SANFORD, D. V., and STACK, M.W. 1996. Chickpea Response to Planting Rate and Rhizobial Inoculation under Variable Water Application Rates. Agron. Abstracts p. 116, Amer. Soc. of Agron., Madison, WI.

Progress 01/01/95 to 12/30/95

Outputs
The dry bean breeding program included the evaluation of over 2000 lines under dryland and irrigated conditions. Advanced generation breeding materials from CSU, CIAT and other sources were evaluated based on seed type, adaptation, and yield potential. The feasibility of garbanzo bean production was evaluated for the second year in Yellow Jacket, CO. Eight experimental lines from ICRISAT and four varieties from California and Washington were tested for their adaptation, disease resistance, and yield potential. They averaged 1,100 kg/ha, well above the average (577 kg/ha) of the dryland pinto bean variety trial. Other alternative crops evaluated in 1995 were edemame beans (edible soybeans) and peppermint. More testing is needed to assess the potential benefits of these two crops in southwestern Colorado. Dryland winter wheat yields were exceptionally high in 1995 due to favorable moisture conditions. The yield averaged over four trials was 2,654 kg/ha, about twice the long-term average for southwestern Colorado. The importance of timely wheat planting was again demonstrated in 1995. Winter wheat planted no later than September 29 outyielded October-planted wheat by an average of 995 kg/ha. A combination of early planting and timely weed control led to non significant differences in grain yield among no-till and minimum-till wheat after fallow, and conventional-till wheat after dry bean. Moreover, wheat yields were not affected by the partial substitution of a cover crop (black lentils) to fallow.

Impacts
(N/A)

Publications

• BERRADA, A., STACK, M.W., SANFORD, D.V., and FISHER, A.G. 1995. Management Systems for Dryland Wheat and Bean Production in Southwestern Colorado- Conservation Tillage Project, 1989-93. Colo. Agric. Exp. Stn. Tech. Bull. TB95-2.
• STACK, M.W., SANFORD, D.V., BERRADA, A. and QUICK, J.S. 1995. Irrigated Spring Wheat Variety Performance Test, 1989-94, Southwestern Colorado Research Center, Yellow Jacket, CO. Colo. Agric. Exp. Stn. Tech. Report TR95-5.
• FISHER, A.G., BRICK, M.A., WOOD, D.R., STACK, M., SCHWARTZ, H.F., OGG, J.B., PEARSON, C.H., SHANAHAN, J.F., and BALLARIN, M. 1995. Registration of 'Fisher' Pinto Bean. Crop Sci. 35:1511
• BERRADA, A., JOHNSON, D.L., SANFORD, D.V., and STACK, M.W. 1995. The Feasibility of Garbanzo Bean Production in Southwest Colorado. Agron. Abstracts p. 120, Amer. Soc. of Agron., Madison, WI.
• BERRADA, A. 1995. Tips on Establishing a Stand of Alfalfa. In The Waterline No. 82, May, 1995. Colo State Univ. Coop. Ext., Colorado River Salinity Control Project.
• BERRADA, A. 1995. Higher Yield, Acreage Potential Exists for Spring Grains in Southwest Colorado. In Montezuma Valley Journal, March 9, 1995.
• SMITH, K. and BERRADA, A. 1995. Production Management of Irrigated Alfalfa. In The Waterline No. 87, October, 1995. Colo State Univ. Coop. Ext., Colorado Rive.

Progress 01/01/94 to 12/30/94

Outputs
Two hundred ninety F3's, 86 F4's, and 115 advanced lines of dry beans were evaluated under dryland conditions and a smaller number under irrigation. Advanced generation breeding materials from CIAT also were evaluated. The dry bean variety Fisher and the spring wheat variety Sylvan were officially released in 1994. Two new varieties of garbanzo beans were evaluated for yield potential and adaptation to southwestern CO. Irrigation research focused on scheduling techniques for dry beans and spring wheat. A new project was initiated to determine the optimum N level for dry bean production under various irrigation regimes. An economic evaluation of reduced tillage systems in southwestern CO was conducted. Several changes were made in the conservation tillage project based on the 1989-1993 results. A study on the efficacy of seed applied insecticides to control Russian wheat aphid and dwarf bunt was initiated in the fall. Fruit tree management investigations were continued for the third year. Eight varieties of grapes were planted to evaluate their potential in southwestern CO. A highly successful field day was held at the Center. Irrigation management, alternative crops, reduced tillage and integrated pest management were featured. The 150 people in attendance was a record number.

Impacts
(N/A)

Publications

Progress 01/01/93 to 12/30/93

Outputs
Dry bean breeding activitiesincluded production and evaluation of 13 F2's, 81 F3's, and 40 advanced lines. All advanced lines were evaluated for reaction to common blight, tolerance to drought stress, and yield potential. The pinto bean line CZ-59196 was evaluated pending its release in 1994. Advanced generation breeding materials from CIAT were evaluated based on seed type, adaptation, and yield potential. A CIAT high altitude adaptation nursery was also grown. Variety yield trials were conducted on irrigated and dryland pinto beans, irrigated spring wheat, irrigated spring barley, irrigated oats,and dryland hard red winter wheat. Three lines of spring wheat UT613960, UT002464 and ID000367 have been identified for possible release in 1994 after four years of testing. Alternative crops were evaluated for adaptation to southwestern Colorado - rapeseed, safflower, crambe, and corn. Irrigation research continued to refine irrigation scheduling techniques for dry beans and spring wheat. A project to evaluate the feasibility of commercial orchards (apple, cherry, peach) in southwestern Colorado was continued for a second year. No-till, minimum and conventional tillage systems for dryland dry bean and winter wheat rotations were evaluated for the fifth year. A summary of the 1989-1993 results has been completed. A study to determine optimum winter wheat planting dates and efficacy of fall applied insecticides as they relate to overwintering of the Russian wheat aphid was continued.

Impacts
(N/A)

Publications

Progress 01/01/92 to 12/30/92

Outputs
Dry edible bean breeding activities included production and evaluation of 27 F1's, 158 F2 and F3 families, and 50 advanced lines. All advanced lines were evaluated for reaction to common blight, adaptation, tolerance to drought stress, and yield potential. Breeder seed was increased of two lines (CZ-59196 and CZ-59191) for production of Foundation seed and varietal release of one of these lines in 1993. Replicated yield trials were conducted on the following crops; irrigated pinto beans, dryland pinto beans, irrigated hard-red spring wheat, irrigated soft white spring and durum wheat, irrigated spring oats, irrigated spring barley, and dryland hard red winter wheat. Field trials were also conducted to determine optimum planting date of winter wheat, and grass host preference for overwintering of the Russian wheat aphid. Large demonstration strips including ten alfalfa varieties and five winter wheat varieties were evaluated for yield. Evaluation of 17 crop management systems comparing no-till, minimum-till and conventional till systems continued. Results regarding specific management practices are still inconclusive. Irrigation research continued to compare sprinkler nozzles and automatic shut-off valves for side-roll sprinklers. Workshops and field days were conducted in the following areas: irrigation techniques, fruit tree production and conservation tillage.

Impacts
(N/A)

Publications

• LEIB, G.B. 1992. Frost protection of fruit tress. Colorado River Salinity Control Project, Colorado State University Cooperative Extension, Water Line No. 49.
• STACK, M.W. 1992. Conservation tillage locally. Montezuma Valley Journal. May 28, 1992.
• LEIB, G.B. 1992. Frost protection for Southwestern Colorado. Montezuma Valley Journal. May 28, 1992.

Progress 01/01/91 to 12/30/91

Outputs
Fifty edible dry bean genotypes were evaluated for yield, leaf movement, leaf temperature and 0-18 isotope ratios at the S.W. Colorado Research Center as a screening process for drought tolerance. At this time results are inconclusive. Edible-dry bean breeding materials including 52 F1, 72 F3, and 81 advanced lines were evaluated for common bactgerial blight, drought resistance and site adaptation. Seed was increased for two experimental lines (CZ 59196 and CZ 59191) being considered for release as varieties. Variety yield trials were conducted for the following crops: 13 irrigated pinto beans; 7 irrigated market class edible-dry beans; 9 dryland pinto beans; 20 irrigated hard-red-spring, soft-white-spring and durum wheat varieties; 12 irrigated spring oat varieties, 17 irrigated spring barley varieties and 20 dry land hard-red-winter wheat varieties. ID-338 hard-red-winter wheat was released as the variety "Fairview" in 1991 and foundation seed was produced for distribution to growers. Evaluation of 17 crop management systems comparing no-till, minimum-till and conventional-till systems continued. No conclusive evidence has yet been revealed. An interagency field day was conducted to showcase the program. Irrigation research included testing and comparing several sprinkler nozzles and developing and testing automatic shut-off valves for side-roll sprinklers. Two irrigation workshops and one field day were held to transfer technology to agriculture producers.

Impacts
(N/A)

Publications

• ZACHARISEN, M.H. 1990. Water-Use Efficiency and Carbon Isotope Discrimination in Dry Beans. M.S. Thesis. Colorado State University, Fort Collins. 66 p.
• STACK, M.W. 1991. Conservation Tillage in Southwestern Colorado. Water Line. No. 46. Colorado River Salinity Control Project, Colorado State University Cooperative Extension, Fort Collins.
• LEIB, G.B. 1991. New Shut-off Valves for Side-Rolls. Water Line, No. 48. Colorado River Salinity Control Project, Colorado State University Cooperative Extension, Fort Collins.