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Area-of-Influence of Herbicide Granules

Published online by Cambridge University Press:  12 June 2017

D. C. Erbach
Affiliation:
Agr. Res. Serv., U.S. Dep. of Agr., Ames, IA 50011
W. G. Lovely
Affiliation:
Agr. Res. Serv., U.S. Dep. of Agr., Ames, IA Agr. Res. Serv., U.S. Dep. of Agr., Beltsville, MD 20705
C. W. Bockhop
Affiliation:
Agr. Eng. Dep., Iowa State Univ., Ames, IA 50011

Abstract

The area influenced by individual herbicide granules was determined by rating control of weeds planted in fixed patterns around granules. The area of foxtail millet [Setaria italica (L.) Beauv.] controlled by alachlor [2-chloro-2′,6′diethyl-N-(methoxymethyl) acetanilide] was larger than the area of velvetleaf (Abutilon theophrasti Medic.) controlled by atrazine [2-chloro-4(ethylamino)-6-(isopropylamino)-s-triazine]. Control was most consistent when granules and seeds were near the same depth and was most variable when granules were on the soil surface. Control of foxtail millet with alachlor increased with increasing soil moisture, with decreasing granule depth, and with increasing seed depth. At low soil moisture, control of velvetleaf with surface-applied atrazine was better with simulated rain than with subirrigation. When soil moisture was high and atrazine granules were placed 1-cm deep, control was better with subirrigation. The area-of-influence, or the control (y) as function of distance (x) from granule, was described by y = 10e-A(x-B)2. The radius-of-control (ROC), defined as the radius of the circular area around a granule within which weeds are effectively controlled, was estimated from this relationship.

Type
Research Article
Copyright
Copyright © 1976 by the Weed Science Society of America 

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References

Literature Cited

1. Amsden, R.C. 1970. The metering and dispensing of granules and liquid concentrates. Brit. Crop Prot. Coun. Monogr. 2:124129.Google Scholar
2. Atkinson, J.D. 1966. TARSIER (FitTing non-lineAr regRession functions by leaSt squares, using the modIfied Gauss-Newton mEthod by H.O. HaRtley): Reference Manual Iowa State University, Statistical Laboratory, Numerical Analysis-Programming Series, No. 8. 18 pp.Google Scholar
3. Byass, J.B. 1968. The physical factors in herbicide application. Brit. Weed Contr. Conf. Proc. 9:13181328.Google Scholar
4. Gunkel, W.W. and Hosokawa, A. 1964. Laboratory device for measuring performance of granular pesticide applicators. Amer. Soc. Agric. Engr., Trans. 7:15.Google Scholar
5. Herr, D.E. and Stroube, E.W. 1970. Velvetleaf control as influenced by herbicide placement and seed depth. Weed Sci. 18:459461.Google Scholar
6. Holly, K. 1970. What is efficient spraying. Brit. Weed Contr. Conf. Proc. 10:11501154.Google Scholar
7. Holzhei, D.E. and Gunkel, W.W. 1967. Design and development of new granular applicators. Amer. Soc. Agric. Engr., Trans. 10:182184.Google Scholar
8. Molnau, M.P., Lovely, W.G. and Johnson, H.P. 1973. Micromovement of propachlor from granules in soil. Weed Sci. 21:185188.Google Scholar
9. Price, D.R. and Gunkel, W.W. 1965. Measuring distribution patterns of granular applicators. Amer. Soc. Agric. Engr., Trans. 8:423425.Google Scholar
10. Reichard, D.L. and Hedden, O.K. 1970. Evaluation of distribution from granular insecticide applicators. U.S. Dep. Agr. ARS-42–169.Google Scholar
11. Ritter, W.F., Johnson, H.P., and Lovely, W.G. 1973. Diffusion of atrazine, propachlor, and diazinon in a silt loam soil. Weed Sci. 21:381384.CrossRefGoogle Scholar
12. Walker, P.T. 1961. Distribution of granules by a commercial hand-operated distributor and their retention on maize plants. Agric. Engr. Res. 6:112118.Google Scholar
13. Whitehead, W.K., Garner, T.H., and Webb, B.K. 1970. How uniform mixing of trifluralin affects weed control Agric. Engr. 51:470471.Google Scholar