Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: August 20, 2008
Publication Date: August 20, 2008
Citation: Rice, C., Bialek Kalinski, K.M., Hively, W.D. 2008. Atmospheric Delivery of Herbicides to Riparian Buffer Zones. Meeting Abstract.
We have evaluated the ability of a riparian buffer to intercept herbicides from the air and deliver them directly by rainfall to a receiving stream in the buffer zone. The study was conducted over a four year period at a site in an agricultural watershed in Maryland. The rain collections included through-fall, stem-flow, and rain collected outside the buffer area. Herbicides are deposited on the leaves of trees and later washed off during rain events. Late application of herbicides, accompanied by high temperature and high humidity and dense foliage, resulted in a very small portion of herbicides in rain collected downwind of the forested area, i.e., less than 5% of that measured beneath the tree canopy. In contrast, these values were nearly 50% for metolachlor and around 30% for atrazine for the early spring application, when temperature and humidity were low and tree foliage less developed.