glyphysate

Have 2 persimmon trees near the house that are turning brown(the leaves that is). Other persimmons elsewhere look o.k. The wife loves round-up and killed a mess of bermuda grass some of which was under these trees.She vehemently denies that this could be damaging the 2 persimmons.I suspect,however, tht round-up even applied to the ground near their roots may have harmed these trees. Anyone know much about this? thanks

In theory and by experience, glyphosate only acts on green leaves or applied directly to the sap flow. It binds up almost instantly with clay particles and does not stay active in the ground at all.

If the trunk was sprayed and had open wounds then perhaps it got into the sap flow, otherwise shouldn't have been a problem?

Paul

She's right. Roundup won't work through the ground or the roots. Has to be applied to the foliage of actively growing plants.

She might not have actually "sprayed the tree" but did she consider any wind drift that day?? Let's just say that her actions probably "caused" the problem.

In her defense, I'm doubting if it will actually kill the tree.........may defoliate it early this year, but probably won't harm it long term.

Somebody has to be the "peacemaker" here.

You can kill trees with round-up--frilling and drill and fill. Saturating the lower portion will kill some trees. Check a chart.

Larry

Glyphosate needs to be applied to green leaves or new (green) branches to kill a tree. Spraying a brown branch or trunk with no wounds does no harm to the tree.

So how could the glyphosate have killed the trees?

Not knowing your lawn care practices we are only guessing from here on.
It could have been caused by wind drift. (have fun proving that to her)
It could have been cause from wounds at the base of the trunk. (have fun denying this is not what happened if you ran a weed eater or mower around the base of the tree in the 2 days prior to her spraying)
But considering this is late summer and persimmon are grafted to a root stock that loves to sucker my best guess and #1 prediction of what happened is she sprayed small sucker shoots growing off the roots of the tree. You may not even notice them as you mow because they are so small and you cut them down with the mower.
Suckers are green and a direct link to the mother tree root system.
I would not give up on them just yet. Let them sit over the winter and see if they leaf out next spring or scrape a little bark at the base of the tree and see if the sap gap is wet and green or dry and brown.

Well to much of a good thing can always be bad. I have 2 spots in a field where I blew a hose on the sprayer. Nothing but round up and it is still bare soil after 3 years. That tells me that your trees could have been affected.