Glyphosate Injury on Apple
Return to Herbicide Injury
Glyphosate (e.g. Roundup) injury symptoms can become evident in spring following a late summer application the previous season. Trees are much more susceptible to injury when this herbicide drifts onto or is inadvertently applied to trees after about July 15. Glyphosate translocates within the tree, moving down to roots in late summer and fall. It is then moved up into the foliage the following spring to produce small willow like leaves. The herbicide may repeat this cycle within the tree for several years. Late season drift is more likely to be lethal to trees than early season drift. The surfactant in Roundup often affects the development of tree winter hardiness, leading to trunk cracking and tree death.
Localized symptoms of glyphosate injury.
(Photo: Mark Longstroth, Michigan State University)
Foliar symptoms of glyphosate injury.
(Photo: Mark Longstroth, Michigan State University)
Management:
- Avoid contact with apple
- Minimize drift (shielded sprayers, low pressure spray, calm days)
