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Duration of Control from Preemergence Herbicides for Use in Nonburned Grass Seed Crops

Published online by Cambridge University Press:  12 June 2017

George W. Mueller-Warrant*
Affiliation:
Agricultural Research Service, USDA, National Forage Seed Production Research Center, 3450 SW Campus Way, Corvallis, OR 97331-7102. E-mail: [email protected]

Abstract

Legislatively mandated reductions in open field burning have increased grass seed growers reliance on herbicides to control seedling grasses in established stands of perennial species. In nonburned fields, a dense flush of seedling weeds and volunteer crop emerges with the onset of fall rains, and additional germination of some species occurs throughout the fall, winter, and spring. Because rainfall patterns in western Oregon are erratic during late summer and early fall, the choice of when to apply preemergence herbicides is difficult. Herbicides applied too early may dissipate before the rains arrive, whereas herbicides applied too late may not prevent germination and seedling establishment. Pendimethalin was least affected by a 3- to 4-wk exposure on dry soil waiting for rain, followed in order of increasing sensitivity by oxyfluorfen, metolachlor, and trifluralin. Most treatments controlled California brome less effectively than perennial ryegrass. Duration of 85% or greater control of subsequently oversown perennial ryegrass averaged 69 d for 2.2 kg/ha pendimethalin, 11 d for 0.42 kg/ha oxyfluorfen, and 4 d for 2.2 kg/ha metolachlor, and duration of 50% or greater control averaged 98, 33, and 18 d for the same treatments. Doubling of herbicide rates doubled the duration of control in 15 out of 27 cases but increased the duration only an average of 75% in the other 12 cases. Average time to doubling of weed populations over those occurring when herbicides and weed seeds were applied on the same day was 12, 10, and 11 d after application for pendimethalin, oxyfluorfen, and metolachlor, respectively. The similarity of these periods suggests that the major difference in performance of these herbicides with time was how close to complete control they had initially achieved. Pendimethalin was the superior preemergence herbicide for controlling California brome and perennial ryegrass in these established stands, but oxyfluorfen and metolachlor also were useful if applied near germination.

Type
Research
Copyright
Copyright © 1999 by the Weed Science Society of America 

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References

Literature Cited

Budd, E. G. and Shildrick, J. P. 1968. Preliminary reports of studies on Poa trivialis (rough-stalked meadow grass) in seed crops. Proc. Br. Weed Control Conf. 9:520526.Google Scholar
Chilcote, D. C., Youngberg, H. W., Stanwood, P. C., and Kim, S. 1980. Postharvest residue burning effects on perennial grass development and seed yield. In Hebblethewaite, P. D., ed. Seed Production. London: Butters-worth. pp. 91103.Google Scholar
Hoerl, A. E. 1954. Fitting curves to data. In Perry, J. H., ed. Chemical Business Handbook. New York: McGraw-Hill Book Co. pp. 5557.Google Scholar
Johnson, J., Scott, J. L., Dibb, C., and Greenwood, M. A. 1982. The effect of controlling volunteer cereals, Poa trivialis and ryegrass seedlings on the seed yield of perennial ryegrass. Proc. Br. Crop Prot. Conf. Weeds, pp. 407414.Google Scholar
Lee, W. O. 1966. Effect of Annual Applications of Diuron on Seed Yields of Perennial Grasses in Oregon. Washington, DC: U.S. Department of Agriculture Technical Bull. 1358. 23 p.Google Scholar
Lee, W. O. 1974. Field Burning Effects on Weed Control in Grass Seed Crops. Corvallis, OR: Agricultural Experiment Station, Oregon State University Research on Field Burning Circ. Info. 647, December 1974. 140 p.Google Scholar
Little, T. M. and Hills, F. J. 1978. Agricultural Experimentation. Design and Analysis. Chapter 14. Curvilinear Relationships. New York: John Wiley and Sons. 350 p.Google Scholar
Mueller-Warrant, G. W. 1994. Weed control in U.S. grass seed crops. Int. Herbage Seed Prod. Res. Group Newsl. 21(December 1994): 710.Google Scholar
Mueller-Warrant, G. W. and Neidlinger, T. J. 1994. Oxyfluorfen controls seedling grasses in established perennial grasses grown for seed. J. Appl. Seed Prod. 12:1425.Google Scholar
Mueller-Warrant, G. W., Young, W. C. III, and Mellbye, M. E. 1994a. Influence of residue removal method and herbicides on perennial ryegrass seed production: I. Weed control. Agron. J. 86:677684.Google Scholar
Mueller-Warrant, G. W., Young, W. C. III, and Mellbye, M. E. 1994b. Influence of residue removal method and herbicides on perennial ryegrass seed production: II. Crop tolerance. Agron. J. 86:684690.Google Scholar
Oswald, A. K. 1985. Effects of three herbicides used to control volunteer ryegrass on tillering and seed yield of two second year perennial ryegrass crops. Weed Res. 25:373379.CrossRefGoogle Scholar
Stahnke, G. K., Shea, P. J., Tupy, D. R., Stougaard, R. N., and Shearman, R. C. 1991. Pendimethalin dissipation in Kentucky bluegrass turf. Weed Sci. 39:97103.CrossRefGoogle Scholar
Young, W. C., Youngberg, H. W., and Chilcote, D. O. 1984. Post-harvest residue management effects on seed yield in perennial grass seed production: I. The effect of less than annual burning when alternated with mechanical residue removal. J. Appl. Seed Prod. 2:4144.Google Scholar
Zimdahl, R. L., Cranmer, B. K., and Stroup, W. W. 1994. Use of empirical equations to describe dissipation of metribuzin and pendimethalin. Weed Sci. 42:241248.CrossRefGoogle Scholar