Progress 10/01/05 to 09/30/10
Outputs
OUTPUTS: Introduced Jose tall wheatgrass and native Barton western wheatgrass were seeded in 2005 in 5.3 ha pastures as part of a cool-season grass/native rangeland complementary grazing system with three replicates to collect animal production and vegetative data. In 2010, moisture was approximately 21% below normal for grass growth through April, but was 4% above normal by July. Grazing commenced with 5 cow/calf pairs per pasture as in prior years. Animals grazed from mid-April to early July for just under 3 months on the cool-season forage. Available forage was 1498 kg/ha and 1303 kg/ha for Jose and Barton at animal removal, and animals removed 59% and 54% of season available forage in Jose and Barton pastures respectively. Cows gained 50.5 kg/hd and calves gained 91.2 kg/hd on Jose (1.82 kg/d/pair), while gains were 95.9 kg/hd and 94.4 kg/hd for cows and calves respectively on Barton (2.44 kg/d/pair). Therefore, total animal production was 134 kg/ha on Jose and 180 kg/ha on Barton. Cows and calves on native rangeland with a high population of indigenous western wheatgrass (18.8% in 2010) gained 97.3 kg/hd and 97.4 kg/hd (2.50 kg/d/pair) during this same time period. During the entire growing season of complementary grass grazing followed by native rangeland grazing from July through September, pairs on tall wheatgrass gained 1.34 kg/d/pair. Cow and calf pairs on western wheatgrass pasture followed by native rangeland grazing, and cow and calf pairs that only grazed on native rangeland from April through October, each gained 1.47 kg/d/pair. Results of this growing season reflect the average over four years; cow gain and calf gain on western wheatgrass and native rangeland during the early grazing season were similar to each other and greater than gain on tall wheatgrass. Introduced perennial cool-season grasses that were seeded under dryland conditions in a randomized complete block design suffered severe stand loss in the drought of 2006. Stands of grasses have slowly increased over 4 years. In 2010, yields of the grasses ranged from 2500-4715 kg/ha. The greatest yield was for Paiute orchardgrass, while summer dormant Flecha tall fescue had the lowest yield. In a separate study of ten perennial cool-season grasses, stand loss occurred in 2006 from summer heat and drought. Most all grasses, except Jose and Alkar tall wheatgrass, have increased stands by nearly 30% and have similar stands as when initially established. In 2010, with precipitation only 10% below normal at the time of harvest, an upland site produced 1700 - 4130 kg/ha of dry matter, while the lowland site produced 1625 - 4060 kg/ha of dry matter. Over the course of four years, intermediate wheatgrass cultivars Oahe and Slate had the greatest average yields of 5490 and 5430 kg/ha on the lowland soil. On the upland soil, Flintlock western wheatgrass and Alkar tall wheatgrass had the greatest average yields of 4835 and 4665 kg/ha. Oahe intermediate wheatgrass also produced an average 4525 kg/ha over four years on the upland soil. PARTICIPANTS: Keith Harmoney - Range and Forage Scientist -Dr. Harmoney is the principal investigator for the project, responsible for experimental design, data collection, data analysis, and interpretation. Collaborators- John Jaeger - Beef Cattle Scientist -Dr. Jaeger provided expertise in measurement of animal production traits, such as animal backfat, marbling score, and muscle depth parameters to distinguish differences in animal characteristics due to differing grazing treatments. Technical Support- Harv Jansonius - Plant Science Technician - Mr. Jansonius provided technical assistance in land preparation, seeding, fertilization, harvesting, sample preparation, forage quality analysis, and animal husbandry during this period of summarization. Wayne Schmidtberger - Animal Science Technician - Mr. Schmidtberger provided expertise in formulating animal rations and general care of livestock when placed in the feedlot to measure subsequent animal performance following grazing periods. Matt Woydziak - Animal Science Technician - Mr. Woydziak provided technical assistance in preparing animal rations for cattle placed in the feedlot. Mr. Woydziak also performed technical duties by scanning animals for backfat thickness, marbling, and muscle depth. Justin Bolte - Animal Science Technician - Mr. Bolte performed common animal husbandry duties for cow/calf pairs, from conception to placement in the feedlot. He also was responsible for collection of data for some animal performance traits. Tom Lang - Animal Facilities Maintenance - Mr. Lang provided technical assistance in feedlot resource maintenance for test animals. All participants are located at the Kansas State University Ag. Research Center at Hays, KS. TARGET AUDIENCES: Target audiences for this project range from scientific professionals, who apply data to related research in their own region, to local and regional producers that can utilize the information for their own agricultural operations. Information from this project is intended to be transferred through refereed publications for the professional scientific community, as well as through local producer informational meetings with oral presentations at county extension offices and field days. PROJECT MODIFICATIONS: No modifications to report.
Impacts
Beef gain from complementary western wheatgrass cool-season forage was similar to beef gain during the same time period from grazing native rangeland with a high population of indigenous cool-season forage. However, beef production from tall wheatgrass during this same early grazing period was lower. Tall wheatgrass is not as beneficial as western wheatgrass for early season beef production at similar stocking rates. Although prior evaluation showed that both tall wheatgrass and western wheatgrass were productive and persistent under moderate to heavy grazing, actual animal performance in this test was greater for the western wheatgrass pastures. Also, the benefit of a cool-season pasture system as a complement to warm-season grass dominated rangelands will be lessened if environmental trends or management allows the cool-season grass component in those native rangelands to become a major dry matter contributor. Since the severe dry season of 2006, most perennial cool-season grasses tested for forage potential have slowly increased in stand percentage and have increased forage production compared to 2006. Recovery of some of these grasses saved potential overseeding or reseeding costs of 195 to 500 dollars/ha to revegetate thinning stands. This emphasizes the need to evaluate animal performance, persistence and production of grasses under grazing and environmental stress and the ability to recover following the stress. Some cool-season forages evaluated may even be useful as both a forage or bioenergy crop.
Publications
- No publications reported this period
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: Introduced Jose tall wheatgrass and native Barton western wheatgrass were seeded in 2005 in 5.3 ha pastures as part of a cool-season grass/native rangeland complementary grazing system with three replicates to collect animal production and vegetative data. In 2009, moisture was approximately 28% below normal for grass growth through July, however, grazing commenced with 5 cow/calf pairs per pasture as in prior years. Animals grazed from early April to early July for 3.1 months on the cool-season forage. Available forage was 1894 kg/ha and 1967 kg/ha for Jose and Barton at animal removal, and animals removed 44% and 54% of season available forage in Jose and Barton pastures respectively. Cows gained 52.4 kg/hd and calves gained 100.7 kg/hd on Jose (1.63 kg/d/pair), while gains were 66.0 kg/hd and 107.8 kg/hd for cows and calves respectively on Barton (1.85 kg/d/pair). Therefore, total animal production was 144 kg/ha on Jose and 164 kg/ha on Barton. Cows and calves on native rangeland with a high population of indigenous western wheatgrass (42.3 % in 2009) gained 84.0 kg/hd and 111.3 kg/hd (2.08 kg/d/pair) during this same time period. Introduced perennial cool-season grasses that were seeded under dryland conditions in a randomized complete block design suffered severe stand loss in the drought of 2006. Paiute orchardgrass and Jose tall wheatgrass had approximately 20% increases and Regar meadowbrome had a 37% increase in stand density from 2006 to the spring of 2009. Flecha summer dormant tall fescue increased in stand 24% from 2006 to 2008, but declined in stand by 12% from 2008-2009 from an extremely dry winter and spring. Forage produced ranged from 751-2667 kg/ha. In a separate study of ten perennial cool-season grasses, stand loss occurred in 2006 from summer heat and drought. Most all grasses, except Jose and Alkar tall wheatgrass, have increased stands by almost 30% to near full stands since 2006. In 2009, with well below normal total spring precipitation, an upland site produced 475 - 2740 kg/ha of dry matter, while the lowland site produced 736 - 3088 kg/ha of dry matter. PARTICIPANTS: Participants: Keith Harmoney - Range and Forage Scientist - Dr. Harmoney is the principal investigator for the project, responsible for experimental design, data collection, data analysis, and interpretation. Collaborators- John Jaeger - Beef Cattle Scientist - Dr. Jaeger provided expertise in measurement of animal production traits, such as animal backfat, marbling score, and muscle depth parameters to distinguish differences in animal characteristics due to differing grazing treatments. Technical Support- Harv Jansonius - Plant Science Technician - Mr. Jansonius provided technical assistance in land preparation, seeding, fertilization, harvesting, sample preparation, forage quality analysis, and animal husbandry during this period of summarization. Wayne Schmidtberger - Animal Science Technician - Mr. Schmidtberger provided expertise in formulating animal rations and general care of livestock when placed in the feedlot to measure subsequent animal performance following grazing periods. Matt Woydziak - Animal Science Technician - Mr. Woydziak provided technical assistance in preparing animal rations for cattle placed in the feedlot. Mr. Woydziak also performed technical duties by scanning animals for backfat thickness, marbling, and muscle depth. Justin Bolte - Animal Science Technician - Mr. Bolte performed common animal husbandry duties for cow/calf pairs, from conception to placement in the feedlot. He also was responsible for collection of data for some animal performance traits. Tom Lang - Animal Facilities Maintenance - Mr. Lang provided technical assistance in feedlot resource maintenance for test animals. All participants are located at the Kansas State University Ag. Research Center at Hays, KS. TARGET AUDIENCES: Target audiences for this project range from scientific professionals, who apply data to related research in their own region, to local and regional producers that can utilize the information for their own agricultural operations. Information from this project is intended to be transferred through refereed publications for the professional scientific community, as well as through local producer informational meetings with oral presentations at county extension offices and field days. PROJECT MODIFICATIONS: No modifications to report.
Impacts
Beef gain from complementary cool-season forages in 2009 was slightly lower than beef gain during the same time period from a native rangeland with a high population of indigenous cool-season forage from two years of high precipitation. This indicates that the benefit of a cool-season pasture system as a complement to warm-season grass dominated rangelands will be lessened if environmental trends or management allows the cool-season grass component in those native rangelands to become a major dry matter contributor. Since the severe dry season of 2006, most perennial cool-season grasses have slowly increased in stand percentage and have increased forage production compared to 2006. Recovery of some of these grasses saved potential overseeding or reseeding costs of 195 to 500 dollars/ha to revegetate thinning stands. This emphasizes the need to evaluate persistence and production of grasses under grazing and environmental stress and the ability to recover following the stress.
Publications
- No publications reported this period
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Native Barton western wheatgrass and introduced Jose tall wheatgrass were seeded in 2005 in 5.3 ha pastures as part of a cool-season grass/native rangeland complementary grazing system with three replicates to collect animal production and vegetative data. In 2008, average moisture was available for grass growth, and grazing commenced with 5 cow/calf pairs per pasture. Animals grazed from mid-April to early July for 2.67 months on the cool-season forage. Available forage was 2760 kg/ha and 1790 kg/ha for Jose and Barton at animal turnout, and 2990 kg/ha and 2390 kg/ha for Jose and Barton at animal removal. Cows gained 41.2 kg/hd and calves gained 72.0 kg/hd on Jose (1.42 kg/d/pair), while gains were 58.6 kg/hd and 76.2 kg/hd for cows and calves respectively on Barton (1.69 kg/d/pair). Therefore, total animal production was 107 kg/ha on Jose and 128 kg/ha on Barton. Cows and calves on native rangeland with an increasing population of indigenous western wheatgrass (59.5%) gained 47.2 kg/hd and 86.3 kg/hd (1.67 kg/d/pair) during this same time period. Introduced perennial cool-season grasses that were seeded under dryland conditions in a randomized complete block design suffered severe stand loss in the drought of 2006. Paiute orchardgrass and Regar meadowbrome had 25-27% increases in stand density from 2006 to the spring of 2008. Jose tall wheatgrass and Flecha summer dormant tall fescue had 21-24% increases in stand from 2006 to 2008. Forage produced ranged from 2610-3480 kg/ha in 2008. In a separate study of ten perennial cool-season grasses, stand loss occurred in 2006 from summer heat and drought. In 2007, grasses produced abundant forage on much above normal precipitation. In 2008, with near normal total spring precipitation, an upland site produced 2330 - 3740 kg/ha of dry matter, while the lowland site produced 2900 - 4810 kg/ha of dry matter. Four of the five highest yielding cultivars in 2008 had an average increase in stand density from 68% to 92% of full stand from the drought of 2006 to the summer of 2008. PARTICIPANTS: Participants: Keith Harmoney, Range and Forage Scientist, is the principal investigator for the project, responsible for experimental design, data collection, data analysis, and interpretation. Collaborators: John Jaeger, Beef Cattle Scientist, provided expertise in measurement of animal production traits, such as animal backfat, marbling score, and muscle depth parameters to distinguish differences in animal characteristics due to differing grazing treatments. Technical Support: Harv Jansonius, Plant Science Technician, provided technical assistance in land preparation, seeding, fertilization, harvesting, sample preparation, forage quality analysis, and animal husbandry during this period of summarization. Wayne Schmidtberger, Animal Science Technician, provided expertise in formulating animal rations and general care of livestock when placed in the feedlot to measure subsequent animal performance following grazing periods. Matt Woydziak, Animal Science Technician, provided technical assistance in preparing animal rations for cattle placed in the feedlot. He also performed technical duties by scanning animals for backfat thickness, marbling, and muscle depth. Justin Bolte, Animal Science Technician, performed common animal husbandry duties for cow/calf pairs, from conception to placement in the feedlot. He also was responsible for collection of data for some animal performance traits. Tom Lang, Agricultural Technician, provided technical assistance in feedlot resource maintenance for test animals. All participants are located at the Kansas State University Agricultural Research Center in Hays, KS. TARGET AUDIENCES: Target audience for this project ranges from scientific professionals to cite data that can be applied to related research in their own region, to local and regional producers that can utilize the information for their own agricultural operations. Information from this project is transferred through professional, refereed publications for the professional scientific community, as well as through local producer informational meetings with oral presentations at county extension offices and field days at the local research center. PROJECT MODIFICATIONS: No modifications to report.
Impacts
The abundant precipitation of 2007 revealed that some perennial cool-season grasses can slowly increase in stand percentage and produce abundant forage in only one season after a drought. With normal precipitation in 2008, some grasses were again able to increase stand density. Recovery of some of these grasses even during a normal precipitation year saved potential overseeding or reseeding costs of 195 to 500 dollars/ha to revegetate thinning stands. This emphasizes the need to evaluate persistence and production of grasses under grazing and environmental stress and the ability to recover following the stress. Furthermore, beef gain in 2008 from a native rangeland with an increasing population of indigenous cool-season forage from two years of high precipitation was nearly equal to beef gain during the same time period from complementary cool-season forages. This indicates that the benefit of a cool-season pasture system as a complement to warm-season grass dominated rangelands will be lessened if environmental trends or management allows the cool-season grass component in those native rangelands to become a major dry matter contributor.
Publications
- No publications reported this period
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Native Barton western wheatgrass and introduced Jose tall wheatgrass were seeded in 2005 in 5.3 ha pastures as part of a cool-season grass/native rangeland complementary grazing system with three replicates to collect animal production and vegetative data. Drought and heat conditions during 2006 did not allow enough cool-season grass growth for grazing on those pastures. In 2007, well above-average moisture was available for grass growth, and grazing commenced with 5 cow/calf pairs per pasture. Established stands were excellent, with a plant frequency in a 0.01 m-square frame of greater than 50% for Jose tall wheatgrass and greater than 80% for Barton western wheatgrass. Grass production was over 9300 kg/ha for Jose and over 6400 kg/ha for Barton during the spring growing season. Animals grazed for 3.3 months on the cool-season forage. Forage disappearance during the early growing season was 4070 kg/ha in Jose and 3880 kg/ha in Barton. Cows gained 34.5 kg/hd and calves
gained 115.6 kg/hd on Jose, while gains were 33.6 kg/hd and 116.5 kg/hd for cows and calves respectively on Barton. Therefore, total animal production was equal at 141.6 kg/ha. Introduced perennial cool-season grasses that were seeded under dryland conditions in a randomized complete block design, suffered severe stand loss in the drought of 2006. Paiute orchardgrass, Regar meadowbrome, and Fawn and Kentucky 31 tall fescue suffered 50 to 90 percent stand loss in 2006. Jose tall wheatgrass and Flecha summer dormant tall fescue had 30 percent or less stand loss. All stands rebounded and increased at least 7 percent by the end of 2007. Paiute and Regar had 17% increases in stand during the much above normal precipitation year of 2007. In a separate study of ten perennial cool-season grasses, stands were not harvested in 2006 because of severe stand loss and lack of growth from summer heat and drought. In 2007, grasses on the upland site produced 5600 - 9700 kg/ha of dry matter, while the
lowland site produced 6770 - 10250 kg/ha of dry matter. Tall wheatgrass and intermediate wheatgrass cultivars that had the greatest stand losses of 2006 recovered to produce some of the greatest yields in 2007.
PARTICIPANTS: Participants: Keith Harmoney - Range and Forage Scientist - Kansas State University Ag. Research Center at Hays, KS. Dr. Harmoney is the principal investigator for the project, responsible for experimental design, data collection, data analysis, and interpretation. Collaborators- John Jaeger - Beef Cattle Scientist - Kansas State University Ag. Research Center at Hays, KS. Dr. Jaeger provided expertise in measurement of animal production traits, such as animal backfat, marbling score, and muscle depth parameters to distinguish differences in animal characteristics due to differing grazing treatments. Technical Support- Harv Jansonius - Plant Science Technician - Kansas State University Ag. Research Center at Hays, KS. Mr. Jansonius provided technical assistance in land preparation, seeding, fertilization, harvesting, sample preparation, forage quality analysis, and animal husbandry during this period of summarization. Wayne Schmidtberger - Animal Science Technician -
Kansas State University Ag. Research Center at Hays, KS. Mr. Schmidtberger provided expertise in formulating animal rations and general care of livestock when placed in the feedlot to measure subsequent animal performance following grazing periods. Matt Woydziak - Animal Science Technician - Kansas State University Ag. Research Center at Hays, KS. Mr. Woydziak provided technical assistance in preparing animal rations for cattle placed in the feedlot. Mr. Woydziak also performed technical duties by scanning animals for backfat thickness, marbling, and muscle depth. Tony Krizek - former Animal Science Technician - Kansas State University Ag. Research Center at Hays, KS. Mr. Krizek performed common animal husbandry duties for cow/calf pairs, from conception to placement in the feedlot. He also was responsible for collection of some animal performance traits. Tom Lang - Facilities Maintenance - Kansas State University Ag. Research Center at Hays, KS. Mr. Lang provided technical assistance
in feedlot resource maintenance for test animals.
TARGET AUDIENCES: Target audience for this project ranges from scientific professionals to cite data that can be applied to related research in their own region, to local and regional producers that can utilize the information for their own agricultural operations. Information from this project is transferred through professional, refereed publications for the scientific community and oral presentations at local producer informational meetings and field days.
Impacts
The heat and drought conditions of 2006 revealed perennial cool-season grass cultivars that are capable of withstanding extreme environmental stress and cultivars that may not survive extreme heat and drought stress. The abundant precipitation of 2007 revealed that these grasses can slowly increase in stand percentage and recover to produce abundant forage if conditions following drought are favorable. Recovery of these grasses from timely rains the season following a drought could save substantial overseeding or reseeding costs of 195 to 500 dollars/ha to revegetate thinning stands if drought conditions had persisted. Avoiding such costs can significantly increase net annual income, and emphasizes the need to evaluate persistence and production of grasses under grazing and environmental stress. Furthermore, beef production in kg/ha from complementary cool-season forages in 2007 was significant, approximately 4 times the beef production from regional native rangelands
at typical stocking rates for the same time period. This indicates producers may be able to generate equal beef production from less native rangeland acres by converting some cropland areas to cool-season forage complements.
Publications
- Harmoney, K.R. 2007. Persistence of Heavily-Grazed Cool-Season Grasses in the Central Great Plains. Online. Forage and Grazinglands doi:10.1094/FG-2007-0625-01-RS.
- Harmoney, K.R. 2007. Grazing and Burning Japanese Brome (Bromus japonicus) on Mixed Grass Rangelands. Rangeland Ecology and Management. 60:479-486.
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Progress 01/01/06 to 12/31/06
Outputs
Introduced perennial cool-season grasses were seeded under dryland conditions in a randomized complete block design and were evaluated for plant density and early production while being intermittently grazed. Winter temperatures were mild, and allowed excellent winter survival of already established plants. The spring and summer of 2006 were exceptionally dry, with January through July precipitation at 50 percent of normal. Yields ranged from only 230 to 1150 kg/ha. Summer heat and drought resulted in a 50 to 90 percent stand loss of Paiute orchardgrass, Regar meadowbrome, and Fawn and Kentucky 31- tall fescue. Jose tall wheatgrass and an experimental summer dormant tall fescue had 30 percent or less stand loss, but had much reduced yield compared to prior seasons. In a separate study, two successive years of heavy grazing were imposed on ten perennial cool-season grasses. In 2006, stands were not grazed, but suffered severe stand loss from summer heat and drought. On
both upland and lowland sites, tall wheatgrass, smooth bromegrass, intermediate wheatgrass, and pubescent wheatgrass suffered 13 to 45 percent stand loss. Native Barton and Flintlock western wheatgrass and introduced Bozoisky Russian wildrye survived the heat and drought without any stand loss. Native Barton western wheatgrass and introduced Jose tall wheatgrass were also seeded the previous year in 5.3 ha pastures to enable collection of animal production data. However, drought and heat conditions during 2006 did not allow enough growth to enable commencement of grazing on those pastures. Pastures will be grazed and animal data collected when ample grass growth has accumulated.
Impacts
The heat and drought conditions of 2006 revealed perennial cool-season grass varieties that are capable of withstanding extreme environmental stress. The heat and drought conditions also revealed cool-season grass varieties that would result in extensive production and stand losses, which in turn results in substantial economic loss from lack of grazing or haying potential. Grasses with less than 75 percent stand survival would likely benefit from overseeding, or reseeding if stands were less than 50 percent, to other adapted grasses or legumes. Depending on variety and seeding rates, reestablishment could cost 195 to 500 dollars/ha, a substantial financial investment in addition to production losses resulting from the lack of stand persistence. Avoiding such costs associated with production and stand losses can significantly increase net annual income, and emphasizes the need to evaluate persistence and production of grasses under grazing and environmental stress.
Publications
- No publications reported this period
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Progress 01/01/05 to 12/31/05
Outputs
Introduced perennial cool-season grasses were seeded under dryland conditions in a randomized complete block design and were evaluated for plant density and early production. Next season, grasses will be evaluated for winter survival and will also be intermittently grazed through the spring and fall to determine effects of defoliation on initial growth and regrowth. Perennial cool-season grasses in a separate respective study had already been established and were extensively defoliated throughout two grazing seasons. Native western wheatgrass cultivars were able to tolerate extensive heat, drought, and grazing stress and had greater persistence in terms of tiller density than introduced smooth brome (SB), tall wheatgrass (TW), intermediate wheatgrass (IW), pubescent wheatgrass (PW), or Russian wildrye (RW) included in the test. In the first recovery year after two seasons of extensive defoliation stress, early spring yield was greatest for Bozoisky RW, largely
resulting from to early maturation compared to other grasses. Spring yield of Barton and Flintlock WW was greater than only one introduced grass cultivar in early spring. By peak production in early summer, Jose and Alkar TW and Barton and Flintlock WW had the four highest yields of grasses included in the test. But western wheatgrass yields were statistically greater than only one introduced cultivar at peak production. Persistence of WW varieties in terms of tiller density was much greater than for other cultivars in early summer. Density was nearly 1200 and 1400 tillers/sq meter greater for WW varieties than for other grasses at two respective locations. Barton WW and Jose TW, which have performed well in yield and persistence trials, have been fall seeded in 5.3 ha pastures. Grasses will be allowed to establish as complementary forage to warm-season grass dominated native rangeland and will be grazed to analyze animal performance.
Impacts
Advancements in forage breeding may be providing new perennial cool-season grass lines that will be adapted to western Kansas. Field trials will determine if these lines are capable of persisting under heat, drought, and grazing stress while providing forage during key periods in early spring and late fall to reduce the need for stored feed for efficient beef production. Stored feed costs $20-30 per month per cow, and reducing stored feed costs by grazing can reduce the major annual cost in beef cow/calf production.
Publications
- Harmoney, K. R. 2005. Growth responses of perennial cool-season grasses grazed intermittently. Online. Forage and Grazinglands doi:10.1094/FG-2005-0105-01-RS.
- Harmoney, K. R., and Thompson, C. A. 2005. Fertilizer rate and placement alters triticale forage yield and quality. Online. Forage and Grazinglands doi:10.1094/FG-2005-0512-01-RS.
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