Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-27T23:11:55.152Z Has data issue: false hasContentIssue false

The Long-Term Effect of Picloram and Its Residue on Grain Production and Weed Control

Published online by Cambridge University Press:  12 June 2017

K. J. Kirkland
Affiliation:
Exp. Farm, Agric. Canada, Scott, Saskatchewan, SOK 4AO Canada
C. H. Keys
Affiliation:
Exp. Farm, Agric. Canada, Scott, Saskatchewan, SOK 4AO Canada

Abstract

The persistence of picloram (4-amino-3,5,6-trichloropicolinic acid) was measured each spring over an 8-yr period following repeated annual applications at rates ranging from 0.020 to 0.070 kg/ha. Picloram residue levels were proportional to rate of application but averaged approximately 45% of the original levels when measured 12 months following application and declined to 10% 24 months after application ceased. Control of wild buckwheat (Polygonum convolvulus L.) was good with major population declines over the test period. Crop tolerance and yields were not affected at rates of 0.035 kg/ha or less.

Type
Research Article
Copyright
Copyright © 1979 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Chang, In-Kook and Foy, C. L. 1971. Effect of picloram on germination and seedling development of four species. Weed Sci. 19:5864.Google Scholar
2. Gaynor, J. D. and Volk, V. V. 1976. Surfactant effects on picloram adsorption by soils. Weed Sci. 24:549552.Google Scholar
3. Goring, C. A. I., Youngson, C. R., and Hamaker, J. W. 1965. Tordon herbicide-disappearance from soil. Down Earth 20(4):35.Google Scholar
4. Grover, R. 1967. Studies on the degradation of 4-amino-3,5,6-trichloropicolinic acid in soil. Weed Res. 7:6167.CrossRefGoogle Scholar
5. Hamaker, J. W., Johnston, H., Martin, R. T., and Redemann, C. T. 1963. A picolinic acid derivative: A plant growth regulator. Science 141:363.Google Scholar
6. Hamaker, J. W., Youngson, C. R., and Goring, C. A. I. 1967. Prediction of the persistence and activity of Tordon herbicide in soils under field conditions. Down Earth 23(2):3046.Google Scholar
7. Herr, D. E., Stroube, E. W., and Roy, D. A. 1966. The movement and persistence of picloram in soil. Weeds 14:248250.Google Scholar
8. Keys, C. H. and Friesen, H. A. 1968. Persistence of picloram activity in soil. Weed Sci. 16:341343.Google Scholar
9. Saha, J. G. and Gadalla, L. A. 1966. Determination of the herbicide Tordon (4-amino-3,5,6-trichloropicolinic acid) in soil by electron capture gas chromatography. J. Assoc. Off. Anal. Chem. 50:637641.Google Scholar
10. Thomas, A. G. 1977. Weed survey of cultivated land in Saskatchewan. Rep. Ag. Can. Res. Stn., Regina. 103 pp.Google Scholar