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Factors Influencing Commercial Aerial Applications of 2,4,5-T

Published online by Cambridge University Press:  12 June 2017

B. J. Eaton
Affiliation:
Oklahoma State University, Stillwater
H. M. Elwell
Affiliation:
Crops Research Division, Agr. Res. Serv., U. S. Dep. of Agr.
P. W. Santelmann
Affiliation:
Oklahoma State University, Stillwater

Abstract

Data were collected on 36 variables including application, environmental, edaphic, and plant conditions during a 3-year study of aerial brush control treatments at 79 sites. These then were correlated with defoliation responses of blackjack oak (Quercus marilandica Muenchh.) and post oak (Quercus stellata Wangenh.) to (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T). The stage of oak growth was of primary importance in obtaining maximum defoliation with 2,4,5-T; the oaks were most susceptible 6 to 8 weeks after the last killing frost. Air temperatures above 90 F, relative humidity below 60%, poor spray coverage and swath widths greater than 50 ft significantly reduced defoliation by 2,4,5-T. Total rainfall during the month before spray application was positively correlated with defoliation by 2,4,5-T, but correlations with rainfall for other time intervals before and after spraying were not significant. Wind above 6 mph at the time of treatment slightly reduced 2,4,5-T effectiveness, but wind direction and dew at spray time did not influence herbicide activity. Application rates of less than 1.75 lb/A were not as effective as higher rates. Aircraft design, spray-water carrier constituents, soil type, soil depth, soil temperature, and topography had no apparent influence on defoliation of oaks by 2,4,5-T.

Type
Research Article
Copyright
Copyright © 1970 Weed Science Society of America 

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References

Literature Cited

1. Basler, E., Todd, G. W. and Meyer, R. E. 1961. Effects of moisture stress on absorption, translocation, and distribution of 2,4-dichlorophenoxyacetic acid in bean plants. Plant Physiol. 36:573576.CrossRefGoogle Scholar
2. Behrens, R. 1957. Influence of various components on the effectiveness of 2,4,5-T sprays. Weeds 5:183196.Google Scholar
3. Dalrymple, A. V. and Basler, E. 1963. Seasonal variation in absorption and translocation of 2,4,5-trichlorophenoxyacetic acid and respiration rates in blackjack oaks. Weeds 11:4145.Google Scholar
4. Darrow, R. A. and McCully, W. G. 1955. Aerial application herbicides for control of post and blackjack oaks. Proc. So. Weed Conf. 8:265268.Google Scholar
5. Elwell, H. M. 1964. Oak control improves grazing land. Agron. J. 56:411415.Google Scholar
6. Elwell, H. M., Elder, C., Klingman, D. and Larson, R. 1954. Aerial applications on oak in Oklahoma. Proc. North Centr. Weed Contr. Conf. 11:91. (Abstr.) Google Scholar
7. Ennis, W. B. Jr. and Williamson, R. E. 1963. Influence of droplet size on effectiveness of low volume herbicidal sprays. Weeds 11:6772.Google Scholar
8. Fisher, C. E. and Young, Dale W. 1950. The effect of herbicide droplet size on the control of mesquite when applied by airplane equipment. Proc. North Centr. Weed Contr. Conf. 7:8486. (Abstr.) Google Scholar
9. Morton, H. L. 1961. Absorption and translocation of 2,4,5-T by mesquite seedlings as influenced by temperature and relative humidity. Proc. So. Weed Conf. 14:325.Google Scholar
10. Ray, H. 1957. New developments in chemical brush control in Arkansas. J. Range Manage. 10:151155.Google Scholar
11. Tschirley, F. H. and Hull, H. M. 1959. The susceptibility of velvet mesquite to an amine and an ester of 2,4,5-T as related to various biological and meterological factors. Weeds 7:427435.Google Scholar
12. Upchurch, R. P., Cobble, H. D., and Keaton, J. A. 1969. Rainfall effects following herbicidal treatments on woody plants. Weed Sci. 17:9498.Google Scholar