RATTAIL FESCUE MANAGEMENT IN WINTER WHEAT

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0228616
• Project Start Date: Jul 1, 2012
• Project End Date: Jun 30, 2017
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIV OF IDAHO
875 PERIMETER DRIVE
MOSCOW,ID 83844-9803

Performing Department
Plant Soil & Entomological Sci

Non Technical Summary
Rattail fescue is difficult to control in direct-seed winter wheat cropping systems with current management tactics, which rely almost exclusively on herbicides (Ball et al 2007, Jemmett et al 2008). Over the past several years, populations of rattail fescue have increased in direct-seed dry land winter wheat production systems in the Palouse region of the PNW. It is not a new weed species in the region; however its incidence is expanding rapidly in circumstances where soil disturbance is minimized in direct- seed systems. Integrated management options for effective rattail fescue control in winter wheat cropping systems have not been adequately investigated and need to be developed. The proposed research will provide Palouse region winter wheat growers with up-to-date, cost-effective, management practices for rattail fescue populations in direct-seed dry land winter wheat cropping systems. Palouse region winter wheat growers will have effective management tools for rattail fescue, which will allow continued use of conservation tillage systems. This will improve farm sustainability, reduce soil erosion, and improve water quality.

Animal Health Component

100%

Research Effort Categories

Basic

(N/A)

Applied

100%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
213	1543	1140	100%

Knowledge Area
213 - Weeds Affecting Plants;

Subject Of Investigation
1543 - Soft white wheat;

Field Of Science
1140 - Weed science;

Keywords

rattail fescue

vulpia myuros

winter wheat

conservation tillage

Goals / Objectives
OBJECTIVE: The effect of tillage type (e.g., chisel plow versus heavy harrow), and tillage duration (e.g., number of growing seasons), with and without herbicide treatment, on rattail fescue populations in a winter wheat cropping system will be determined. EXPECTED OUTCOMES: The occurrence of rattail fescue is increasing in direct-seed cropping systems, and control can be difficult. Additionally, over use of group 15 herbicides may result in selection of HR biotypes, which will make control more difficult, increase production costs and reduce farm profitability. Long-term effective rattail fescue control will require development of integrated management tactics (i.e., beyond simply using group 15 herbicides alone or in combination with other herbicides). The proposed research will provide Palouse region winter wheat growers with up-to-date, cost-effective, management practices for rattail fescue populations in direct-seed dry land winter wheat cropping systems.

Project Methods
Field experiments will be established in fall 2012 near Moscow, ID at the University of Idaho Parker Research Farm, and near Genesee, ID at the Kambitsch Research Farm. To obtain a uniform weed population, rattail fescue will be seeded into a cultivated field during fall 2012 at 18 kg per ha. Rattail fescue stand density will be determined during spring 2013 by counting the number of plants at 10 random locations at each study site. Rattail fescue plants will be allowed to mature and produce seed during summer 2013. No crop will be planted during the first year of the study and no tillage treatments will be initiated to allow establishment of a uniform rattail fescue population. During the second growing season, winter wheat will be uniformly seeded across each site during fall 2013 and grown using typical agronomic practices for the area. Rattail fescue stand density will be determined during spring 2014 at 10 random locations at each study site, and will be allowed to grow and produce seed in the wheat crop. Tillage and rattail herbicide control treatments will begin during fall 2014 and will range from no tillage to tillage each year for a maximum of three years. Three years was selected as the maximum tillage duration because seed burial studies indicated that a majority of buried rattail fescue seed was not viable after 2 to 3 years. Tillage treatments will be chisel plowed in the fall followed by one or two field cultivations in the spring, and heavy harrow in the fall followed by direct seeding in the spring. Plots will be heavy harrowed following spring pea harvest and prior to seeding winter wheat in tillage treatments. Tillage treatments will be imposed for one, two, or three year of a three year crops rotation (spring wheat in 2015 - spring pea in 2016 - winter wheat in 2016-17). A no-tillage treatment will be included as a control. Tillage plots will be split into with and without herbicide treatments used to control rattail fescue. Flufenacet/ metribuzin will be applied to winter wheat and rattail fescue. Rattail fescue control will be estimated visually two times to quantify early- and late-season control, and aboveground biomass will be collected at or near seed maturity. Winter wheat will be harvested at crop maturity using a small-plot combine. Harvested grain will be cleaned, and yield and test weight will be measured. Each experiment will be designed as a randomized complete block, split-plot with four replications. Data will be analyzed using ANOVA procedures. Data will be analyzed using ANOVA procedures and orthogonal contrasts to compare specific treatments.

Progress 07/01/12 to 06/30/17

Outputs
Target Audience:Growers, chemical industry researchers and marketers, local agricultural seed and chemical dealers and field scouts, university extension personnel, university and USDA researchers, university students, private agriculture contractors. 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?Experimental results were presented at regional, local, and state meetings. Results were shown on field tours. Data was published in progress reports.Results were discussed with individual growers and agricultural support personnel. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? IMPACT Reduced tillage, especially direct-seeding, has resulted in increased populations of rattail fescue in winter wheat systems in the Pacific Northwest. Rattail fescue is controlled with conventional tillage. The question often asked by wheat growers has been how much tillage is enough? Also, available herbicides were not effective for rattail fescue control. Rattail fescue populations were reduced with low soil disturbance tillage, but the best control was with chisel plow more than one year. Rattail fescue control is increased with the addition of pyroxasulfone herbicide. This herbicide was labeled for use on wheat in 2014. Pyroxasulfone used alone controls rattail fescue populations up to 99% in winter wheat with little to no crop injury. Wheat growers will be able to manage rattail fescue populations with a combination of minimum tillage and pyroxasulfone herbicide. Accomplishments Rattail fescue control was evaluated with pyroxasulfone containing herbicides alone or in combination in winter wheat in 2012 through 2014 near Moscow, ID. The plots were arranged in a randomized complete block design with four replications and included an untreated check. All herbicide treatments were applied using a CO2 pressurized backpack sprayer calibrated to deliver 10 gpa at 32 psi and 3 mph. The sites were oversprayed with pyrasulfotole/bromoxynil at 0.19 lb ai/A and thifensulfuron/tribenuron at 0.031 lb ai/A for broadleaf weed control and with fluxapyroxad/pyraclostrobin at 0.13 lb ai/A for stripe rust control. Crop injury and grass weed control were evaluated visually during the growing season. Grain was harvested with a small plot combine at maturity. All treatments containing flufenacet/metribuzin visibly injured winter wheat 16 to 39% on June 5, 2017. Rattail fescue was controlled 94 to 99% by all treatments containing flufenacet/metribuzin or pyroxasulfone. Flucarbazone, pyroxsulam, or sulfosulfuron applied alone postemergence did not controlled rattail fescue (60 to 66%). In the past, flucarbazone has suppressed rattail fescue averaging 76% control over 9 observations, but it performed poorly in 2017 most likely due to poor crop competition from non-uniform wheat stand. Wheat grain yield was highest with pyroxasulfone plus fluthiacet at 4570 kg per ha, least with sulfosulfuron at 3420 kg per ha. Wheat grain yield in the nontreated check was 2956 kg per ha and all treatments except sulfosulfuron yielded higher than the nontreated. Winter wheat test weight was lowest (79 kg per hL) in the nontreated check. Results are similar for experiments in 2012 through 2016. Wheat stand in the tillage experiment in 2017 was compromised by flooding at one site and rodent feeding injury at the other.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Rauch, T.A and J.M. Campbell. 2016. Rattail fescue control in winter wheat. Research Progress Report. Western Society of Weed Science. p. 110-111
• Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2018 Citation: Rauch, T.A and J.M. Campbell. 2018. Rattail fescue and downy brome control in winter wheat. Research Progress Report. Western Society of Weed Science. (in press)
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Rauch, T.A and J.M. Campbell. 2017. Rattail fescue control in winter wheat. Research Progress Report. Western Society of Weed Science. p. 89-91

Progress 10/01/15 to 09/30/16

Outputs
Target Audience:Growers, chemical industry researchers and marketers, local agricultural seed and chemical dealers and field scouts, university extension personnel, university and USDA researchers, university students, private agriculture contractors. 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?Extension meetings, public field tours What do you plan to do during the next reporting period to accomplish the goals?Complete the resesarch as outlined in the proposal which includes weed counts and wheat yield.

Impacts
What was accomplished under these goals? Knowledge of cultural controls, crop rotation and tillage is limited for rattail fescue control. Current information is speculative at best. Herbicide usageis the only known research-based tool for rattail fescue control. This data will help growers take an integrated weed management approach to reducing rattail fescue and increasing crop yield. A field trial was established at UI research farms near Moscow and Genesee to examine tillage effects on rattail fescue. Winter wheat was direct-seeded in fall 2013. The rotation is winter wheat - spring wheat - spring chickpea. Tillage initiated in the fall 2014 included fall disc or chisel plow followed by spring field cultivation. A no-tillage treatment is included as a control. Heavy harrow replaced disc in year 2 and 3. The tillage is performed all 3 years, 2 years or 1 year for a total ofseven tillage regimes. Spring wheat was seeded in 2015. Each tillage was split into Zidua applied pre-emergence, Zidua pre-emergence followed by Everest post emergence, and an untreated check. Rattail fescue populations were highest in untreated no-till at both sites. Chickpea was planted in 2016 and rattail fescue populations were low. Low populations were likely due to winter kill and effective glyphosate application in the spring that suppressed rattail fescue growth in 2016. The weed was found only in no-tillage and the one year of chisel plow treatments. Yield was highest (4480 kg per ha) with two years of fall chisel, and lowest (3998 kg per ha) with one year disc, but there were no statistical differences among treatments due to low rattail fescue plant density. Final year of winter wheat will be harvested in 2017.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Campbell, J. and T. Rauch. 2016. Mustard compared to a legume in a wheat cropping system. 7th International Weed Science Congress Proceedings, Prague, Czech Republic, p 342. Campbell, J,T. Rauch, and M. Anderson. 2016. Rotational Crops Response to Mesosulfuron/Thiencarbazone Applied in Prior Wheat Crop. Western Society of Weed Science Proceedings 69:24.

Progress 10/01/14 to 09/30/15

Outputs
Target Audience:Commodity Commissions, Growers, Agronomists, Farmer Cooperatives, County Education Educators, Students 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?Public field days What do you plan to do during the next reporting period to accomplish the goals?Continue the planned research as outlined in the proposal. Tillage treatments will be continued and the rotational pea crop planted, weeds assessed, and peas harvested.

Impacts
What was accomplished under these goals? Outcomes/Impacts: Knowledge of cultural controls, crop rotation and tillage is limited for rattail fescue control. Current information is speculative at best. Herbicide usage in is the only known research-based tool for rattail fescue control. This data will help growers take an integrated weed management approach to reducing rattail fescue and increasing crop yield. A field trial was established at UI research farms near Moscow and Genesee to examine tillage effects on rattail fescue. Winter wheat was direct-seeded in fall 2013. The rotation is winter wheat-spring wheat-spring pea. Tillage initiated in the fall 2014 included fall disc or chisel plow followed by spring field cultivation. A no-tillage treatment is included as a control. Heavy harrow will replace disc in year 2 and 3. The tillage is performed all 3 years, 2 years or 1 year for a total of 7 tillage regimes. Spring wheat was seeded in 2015. Each tillage was split into Zidua applied preemergence, Zidua pre-emergence followed by Everest postemergence, and an untreated check. Rattail was highest in untreated no-till at both sites. In no-till, Zidua reduced the population compared to the untreated and adding Everest reduced the population further. Rattail population was highest in no-till and least in chisel treatments. Rattail density was higher at Moscow than Geneseee and this resulted in a yield response at Moscow. Chisel, disc, and no-till plots yielded 3582, 3137, and 2926 lb/A, respectively. Test weight was not affected.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Rauch, T.A and J.M. Campbell. 2015. Rattail fescue and downy brome control in winter wheat. Research Progress Report. Western Society of Weed Science. p. 66-67.

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

Outputs
Target Audience: Wheat growers, university researchers and extension personnel, agricultural field representatives of seed and chemical companies . 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? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Spring crops will be planted, rattail fescue will be evaluated visully and biomass will be measured for each treatment. Wheat will be harvested and fall tillage will continue on two of the three treatments. Herbicide treatments will be evaluated for rattail fescue control at two locations in winter wheat.

Impacts
What was accomplished under these goals? Rattail fescue was seeded during fall 2012 at University of Idaho research farms near Moscow and Genesee to establish long term field trials to examine the effect of tillage on rattail fescue populations in direct-seeded wheat. No crop was planted and no tillage treatments were implemented the first year to allow establishment of a uniform rattail fescue population. Winter wheat was direct-seeded in fall 2013 at both locations and harvested in August 2014. A three year crop rotation (winter wheat-spring wheat-spring pea) will be used for the experiments. Tillage was initiated in the fall 2014. Tillage will be imposed during year one, two and three of the crop rotation. Tillage treatments include: fall chisel plow or fall discing followed by spring field cultivation. A no-tillage treatment will be included as a control. Each tillage plot will be split into with and without herbicide treatment. The experimental design is a randomized complete block, split-plot with four replications. Herbicide treatments will be initiated and spring wheat will be planted in spring 2015. In two herbicide comparison studies, rattail fescue control in winter was evaluated for preemergence applications of pyroxasulfone and flufenacet/metribuzin alone and combined with postemergence applications of pyroxsulam, flucarbazone/thifensulfuron, and sulfosulfuron. Rattail fescue control is 85 to 97% with all preemergence treatments. Postemergence herbicides alone do not provide adequate rattail fescue control, but flucarbazone postemergence following preemergence herbicides improve control.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2014 Citation: Rauch, T., J. Campbell and D. Thill. March 10-13, 2014. Winter Wheat Tolerance and Grass Weed Efficacy with Pyroxasulfone Combinations. Western Society of Weed Science, Colorado Springs, Colorado.http://www.wsweedscience.org/wp-content/uploads/2013/09/2014WSWS_Proceedings_Final.pdf

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

Outputs
Target Audience: Wheat growers, university researchers and extensionpersonelle, agricultural field representatives of seed and chemical companies. 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? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? The research will be discussed briefly at a field tour. The treatments will initiated.

Impacts
What was accomplished under these goals? A uniform population of rattail fescue was established at two locations in Idaho. Winter wheat will beseeded in October 2013. Tillage and rotations will begin after wheat harvest in August 2014.

Publications

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

Outputs
OUTPUTS: Rattail fescue seed was sown into fallow fields on October 24th and October 27th , 2012 at the University of Idaho Research Farms at Moscow and Genesee, Idaho, respectively, to increase uniformity of the weed population. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Agricultural producers, Agricultural industry personnel, County Extension Educators, Weed Science Researchers and Educators. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Rattail fescue populations are kept in check with conventional tillage systems. Some farmers who use reduced tillage are developing rattail fescue populations in winter wheat cropping systems. The minimal tillage timing, type, and duration required to control rattail fescue is unknown. This research will determine the level of minimum tillage production necessary to control rattail fescue in a winter wheat production system.

Publications

• No publications reported this period