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Percent Spotted Knapweed (Centaurea stoebe) in the Diets of Grazing Sheep

Published online by Cambridge University Press:  20 January 2017

Lisa M. M. Surber
Affiliation:
Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717
Mark E. Rude
Affiliation:
Montana State University, Bozeman, MT 59717
Brent L. Roeder
Affiliation:
Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717
Tracy K. Mosley
Affiliation:
Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717
Allison V. Grove
Affiliation:
AG Research, L.L.C., P.O. Box 892, White Sulphur Springs, MT 59645
John W. Walker
Affiliation:
Texas AgriLife Research and Extension Center at San Angelo, San Angel, TX 76901
Rodney W. Kott*
Affiliation:
Department of Animal and Range Sciences, Montana State University, Bozeman, MT 59717
*
Corresponding author's E-mail: rkott@montana.edu

Abstract

The objective of this study was to use fecal near-infrared reflectance spectroscopy (NIRS) to estimate the percent spotted knapweed in the diet of grazing ewes to fine tune grazing prescriptions. In trial 1, five ewes were randomly selected from a band of 900 ewes to estimate weekly variation in percent spotted knapweed in the diet. Fecal samples from these ewes were collected weekly from June 22 through August 17 (nine collections per ewe for a total of 45 observations). In trial 2, fecal samples were collected from 89 ewes in the band to estimate variability in percent spotted knapweed in the diet among sheep at two sampling dates corresponding to the bud (July 13) and postflowering (August 15) stages of spotted knapweed phenology. In trial 1, the percent spotted knapweed in the diet was similar (P > 0.05) on June 22, June 29, July 13, and July 20 but was greater (P < 0.05) on July 6 than June 22 and 29. Percent spotted knapweed in the diet was also greater (P < 0.05) from July 27 through August 17 than from June 22 through July 20. On July 13 in trial 2, 55% of ewes had 0 to 5% spotted knapweed in their diets, whereas 44% of ewes had 5 to 20% spotted knapweed in their diets. On August 15, only 1% of ewes had < 10% spotted knapweed in their diets, whereas 44% of ewes had 20 to 25% spotted knapweed in their diets. The estimated percent spotted knapweed in the diet of the 89 ewes in trial 2 was similar to that of the five ewes during the same time period in sampling trial 1 (5.3% compared with 5.0% for sampling trials 1 and 2, respectively, on July 13 and 22.0% compared with 20.7% on August 15 and 17 for trials 1 and 2, respectively). This is the first study to estimate percent spotted knapweed in the diet of individual grazing ewes. These data suggest that the best time to graze spotted knapweed–infested pastures would be in late July or early August, when spotted knapweed is flowering, but before viable seed production.

Type
Research
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Benzel, K. R., Mosley, T. K., and Mosley, J. C. 2009. Defoliation timing effects on spotted knapweed seed production and viability. Rangeland Ecol. Manage 62:550556.CrossRefGoogle Scholar
[BLM] U.S. Department of the Interior–Bureau of Land Management 1996. Sampling Vegetation Attributes: Interagency Technical Reference 1734-4. Denver, CO BLM National Applied Resource Sciences Center. 163 p. BLM/RS/ST-96/002+1730. Supersedes BLM Technical Reference 4400-4, Trend Studies, dated May 1995.Google Scholar
Davison, J. C., Smith, E., and Wilson, L. M. 2007. Livestock Grazing Guidelines for Controlling Noxious Weeds in the Western United States. Reno, NV University of Nevada Experimental Station Bulletin EB-06-05.Google Scholar
Foss, . 2000. WinISI II Training Handbook. Silver Spring, MD Foss NIRSystems.Google Scholar
Ganguli, A. C., Hale, M. B., and Launchbaugh, K. L. 2010. Seasonal change in nutrient composition of spotted knapweed and preference by sheep. Small Rum. Res 89:4750.Google Scholar
Griffith, D. and Lacey, J. R. 1991. Economic evaluation of spotted knapweed [Centaurea maculosa] control using picloram. J. Range Manage 44:4347.Google Scholar
Hale, M. 2002. Developing Prescription Grazing Guidelines for Controlling Spotted Knapweed with Sheep. Pages 75 p. M.S. thesis. Moscow, ID: University of Idaho.Google Scholar
Kelsey, R. G. and Mihalovich, R. D. 1987. Nutrient composition of spotted knapweed (Centaurea maculosa). J. Range Manage 40:277281.CrossRefGoogle Scholar
Launchbaugh, K. L. and Walker, J. W. 2006. Targeted grazing—a new paradigm for livestock management. Pages 28. In Launchbaugh, K. L., Walker, J. W., and Daines, R. L. eds. Target Grazing: A Natural Approach to Vegetation Management and Landscape Enhancement. Centennial, CO American Sheep Industry Association.Google Scholar
Lyons, R. K. and Stuth, J. W. 1992. Fecal NIRS equations for predicting diet quality of free-ranging cattle. J. Range Manage 45:238244.Google Scholar
Mueggler, W. F. and Stewart, W. L. 1980. Grassland and shrubland habitat types of western Montana. Odgen, UT U.S. Department of Agriculture Forest Service. 155 p. Intermountain Forest and Range Experiment Station General Technical Report INT-66.Google Scholar
[NRCS] Natural Resources Conservation Service 2003. Soil Survey of Powell County Area, Montana: Pt. 1 (288 p.) and Pt. 2 (67 p.). USDA–NRCS.Google Scholar
Olson, B. E. and Kelsey, R. G. 1997. Effect of Centaurea maculosa on sheep rumen microbial activity and mass in vitro. J. Chem. Ecol 23:11311144.Google Scholar
Olson, B. E. and Launchbaugh, K. L. 2006. Managing herbaceous broadleaf weeds with targeted grazing. Pages 5766. In Launchbaugh, K. L., Walker, J. W., and Daines, R. L. eds. Target Grazing: A Natural Approach to Vegetation Management and Landscape Enhancement. Centennial, CO American Sheep Industry Association.Google Scholar
Olson, B. E. and Wallander, R. T. 2001. Sheep grazing spotted knapweed and Idaho fescue. J. Range Manage 54:2530.CrossRefGoogle Scholar
Patten, D. D. 2009. The Response of a Spotted Knapweed Dominated Community to Selective Defoliation at Different Phonologies. Pages 56 p. M.S. thesis. Moscow, ID: University of Idaho.Google Scholar
Roché, B. F. Jr and Talbott, C. J. 1986. The collection history of centaureas found in Washington State. Agric. Res. Cent., Wash. State Univ. Res. Bull. XB 0978.Google Scholar
SAS 2004. SAS Procedures Guide. Version 9.1, 3rd ed. Cary, NC SAS Institute.Google Scholar
Thrift, B. D., Mosley, J. C., Brewer, T. K., Roeder, B. L., Olson, B. E., and Kott, R. W. 2008. Prescribed sheep grazing to suppress spotted knapweed on foothill rangeland. Rangeland Ecol. Manage 61:1825.Google Scholar
Tyser, R. W. and Key, C. H. 1988. Spotted knapweed in natural area fescue grasslands: an ecological assessment. Northwest Sci 62:151160.Google Scholar
[USDA-NRCS] United States Department of Agriculture–Natural Resources Conservation Service 2009. The PLANTS Database. Baton Rouge, LA National Plant Data Center. http://plants.usda.gov. Accessed: July 2, 2009.Google Scholar
Walker, J. W., Campbell, E. J., Kott, R. W., Landau, S. Y., Lupton, C. J., Scott, C. B., Surber, L., Taylor, C. A. Jr, and Whitworth, W. R. 2010. Chapter 5: Fecal NIRS for predicting botanical composition of herbivore diets. Pages 5365. In Walker, J., Tolleson, D., and Byrns, S. eds. Shining Light on Manure Improves Livestock and Land Management. Jefferson City, MO Texas AgriLife Research and Society for Range Management.Google Scholar
Walker, J. W., Campbell, E. S., Lupton, C. J., Taylor, C. A. Jr, Waldron, D. F., and Landau, S. Y. 2007. Effects of breed, sex, and age on the variation and ability of fecal near-infrared reflectance spectra to predict the composition of goat diets. J. Anim. Sci 85:518526.Google Scholar
Walker, J. W., Clark, D. H., and McCoy, S. D. 1998. Fecal NIRS for predicting percent leafy spurge in diets. J. Range Manage 51:450455.Google Scholar
Walker, J. W., McCoy, S. D., Launchbaugh, K. L., Fraker, M. J., and Powell, J. 2002. Calibrating fecal NIRS equations for predicting botanical composition of diets. J. Range Manage 55:374382.Google Scholar
[WRCC] Western Regional Climate Center 2009. Historical Climate Information. Ovando 9 SSE, Montana (246304). http://www.wrcc.dri.edu. Accessed: July 8, 2009.Google Scholar
Wright, A. L. and Kelsey, R. G. 1997. Effects of spotted knapweed on a cervid winter–spring range in Idaho. J. Range Manage 50:487496.Google Scholar