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Quackgrass (Agropyron repens) Control in Established Alfalfa (Medicago sativa) With Pronamide

Published online by Cambridge University Press:  12 June 2017

R. S. Fawcett
Affiliation:
Dep. of Bot., and Plant Pathol., Iowa State Univ., Ames, IA 50011
R. G. Harvey
Affiliation:
Dep. of Agron., Univ. of Wisconsin, Madison, WI 53706
D. A. Schlough
Affiliation:
Ashland Exp. Farm, Ashland, WI
I. R. Block
Affiliation:
Marshfield Exp. Farm, Marshfield, WI

Abstract

The degree and longevity of quackgrass [Agropyron repens (L.) Beauv.] control provided by autumn applications of pronamide [3,5-dichloro(N-1,1-dimethyl-2-propynyl)benzamide] was influenced greatly by alfalfa (Medicago sativa L.) stand density, as well as by rate of application and soil type. When applications were made to a field with a sparse alfalfa stand (10 to 20 crowns/m2), quackgrass yields were reduced the year following pronamide application, but quackgrass reinfested the plots the second year after treatment. Quackgrass yields one and two seasons following autumn treatment with 2.2 kg/ha pronamide were 1480 and 3890 kg/ha compared to 4480 and 4870 kg/ha for control plots. Annual applications of pronamide were necessary to maintain quackgrass control in the sparse alfalfa stand. Pronamide application to a vigorous, dense alfalfa stand (40 to 50 crowns/m2) provided quackgrass control which persisted into the second year after treatment. Quackgrass control ratings one and two seasons after application of 1.1 kg/ha pronamide were 100 and 90%. Pronamide treatments reduced first cutting quackgrass yields, and increased first cutting alfalfa yields. Treatment of the sparse alfalfa stand with 2.2 kg/ha pronamide resulted in first cutting alfalfa and quackgrass yields of 2420 and 990 kg/ha compared to 1430 and 3940 kg/ha for controls. Treatment of a dense alfalfa stand with 1.1 kg/ha pronamide resulted in first cutting alfalfa and quackgrass yields of 3850 and 300 kg/ha compared to 1710 and 1660 kg/ha for controls. Total herbage yields from all cuttings were either slightly decreased when fields with sparse alfalfa stands were treated or remained constant or slightly increased when more dense alfalfa stands were treated. Pronamide applied with potash as the carrier was as effective as when applied in water. Pronamide treatment resulted in increased crude protein concentration in first cutting herbage at all locations in all years. Crude protein concentration in first cutting control herbage ranged from 13.3 to 16.1%. Crude protein concentration in first cutting herbage from plots treated with 1.1 kg/ha pronamide ranged from 17.7 to 20.6%, depending on year and location. In vitro digestible dry matter (IVDDM) concentrations were increased by most rates of pronamide in first, second, and third cutting herbage. IVDDM for first cutting control herbage was 51.4% compared to 61.3% for herbage treated with 2.2 kg/ha pronamide. Acid detergent fiber concentration in first cutting herbage was not affected by pronamide.

Type
Research Article
Copyright
Copyright © 1978 by the Weed Science Society of America 

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References

Literature Cited

1. A.O.A.C. 1970. Official Methods of Analysis (11 ed.). Association of Analytical Chemists. Washington, DC, p. 123.Google Scholar
2. Duke, W. B. 1969. RH-315 for quackgrass control in established alfalfa. Proc. Northeast. Weed Control Conf. 23:26.Google Scholar
3. Duke, W. B. 1970. Effects of RH-315 on quackgrass and established alfalfa. Proc. Northeast. Weed Control Conf. 24:220.Google Scholar
4. Fawcett, R. S. and Harvey, R. G. 1975. Long-term studies with pronamide for quackgrass control in alfalfa. Proc. North Cent. Weed Control Conf. 30:4546.Google Scholar
5. Harvey, R. G. 1973. Quackgrass control in alfalfa with pronamide. Proc. North Cent. Weed Control Conf. 28:38.Google Scholar
6. Harvey, R. G. and Baker, C. R. 1974. Influence of herbicides on couch bud development. Weed Res. 14:5763.Google Scholar
7. Harvey, R. G. and Connor, S. R. 1971. Selective control of quackgrass in alfalfa with RH-315. Proc. North Cent. Weed Control Conf. 26:6869.Google Scholar
8. Ilnicki, R. D. and Hist, L. P. 1969. Weed control in dormant alfalfa. Proc. Northeast. Weed Control Conf. 23:222.Google Scholar
9. Johnson, B. G. and Buchholtz, K. P. 1962. The natural dormancy of vegetative buds on the rhizomes of quackgrass. Weeds 10:5357.Google Scholar
10. Peterson, R. L. and Smith, L. W. 1971. Effects of N-(1,1-dimethylpropynyl)-3,4-dichlorobenzamide on the anatomy of Agropyron repens . Weed Res. 11:8487.Google Scholar
11. Schirman, R. and Buchholtz, K. P. 1966. Influence of atrazine on corn and rhizome carbohydrate reserves of quackgrass. Weeds 14:233236.CrossRefGoogle Scholar
12. Smith, L. W., Peterson, R. L., and Horton, R. F. 1971. Effects of a dimethylpropynyl benzamide herbicide on quackgrass rhizomes. Weed Sci. 19:174177.Google Scholar
13. Tilley, J. M. A. and Terry, R. A. 1963. A two-stage technique for the in vitro digestion of forage crops. J. Br. Grassl. Soc. 18:104.Google Scholar
14. Viste, K. L. and Sanborn, J. M. 1970. Control of quackgrass (Agropyron repens) in alfalfa. RH-315 (Kerb). Proc. Northeast. Weed Control Conf. 24:227231.Google Scholar
15. Van Soest, P. J. 1963. The use of detergents in the analysis of fibrous feeds. II. A rapid method for the determination of fiber and lignin. J. Assoc. Off. Agric. Chem. 46:829.Google Scholar
16. Walker, J. D., Triplet, G. B., and Van Keuren, R. W. 1974. The influence of herbicides on quality and yield in forage management systems. Proc. North Cent. Weed Control Conf. 29:57.Google Scholar