Determination of herbicide spread factors
Authors: Yoshida, K. And J. Maybank
Description: One of the inherent problems in pesticide spraying is that of control ling droplet size. A few attempts have been made to determine the droplet sizes, or number of droplets per unit area receiving surface, which would be biologically most effective for the various types of treatments. The importance of droplet size on herbicide efficiency has been investigated. With low-volume applications, Ennis and Williamson (9) observed higher effectiveness with decreasing droplet size. On the other side, Behrens (2) reported that droplet spacing was of major importance in herbicidal effectiveness on mesquite, with no direct influence due to the droplet size or the volume. The minimum number of droplets needed to obtain maximum effectiveness was 72 per square inch, regardless of size within the range of 200 to 800 microns diameter. Excessively large droplets result in a serious waste of material, and very small droplets present a serious drift problem. While investigating the factors affecting the use of airblast sprays, Brann Jr. (4) indicated that in New York state the cost of spray materials represented about 75% of the total cost of insect control spraying. For these reasons, spray droplet size and the range of sizes or droplet spectrum in a given spray have be come important factors in evaluating a spray distribution and in predicting a spray drift.
Keywords: determination of herbicide spread factors
Citation: Yoshida, K. and J. Maybank 1969. DETERMINATION OF HERBICIDE SPREAD FACTORS. Canadian Agricultural Engineering 11(2):66-70.
Start page number: 66
End page number: 70