Thursday, August 19, 2010
Glyphosate damage on ash tree.
This photo of an ash tree shows symptoms of glyphosate uptake. Glyphosate, initially sold as Roundup by Monsanto, is now available in generic form at many farm cooperatives, and retail businesses. When this product is misapplied it can cause damage. In this case the owner sprayed glyphosate to control weeds at the base of the tree last year. These symptoms appeared this year.
Glyphosate may drift onto the buds or be taken in through green tissue at the base of tree .
Symptoms of glyphosate toxicity the year after glyphosate uptake results in clusters of leaves where shoots should develop. I've seen these same symptoms on trees in local retail nurseries where the wholesale nursery applied glyphosate to control weeds around the trees the previous year. These symptoms are also occasionally seen on grape vines when glyphosate is used to control weeds at the base of the vines.
Herbicides should be used with care. Don't assume they are safe.