If the material you applied contains glyphosate as the active ingredient, as most Roundup formulations do, and you followed label directions, it should not be affecting your tree in this way. Once it hits soil, glyphosate is not herbicidally active. Of course if it drifted off target or you applied it to the leaves, or green bark or branches, or sprouts of the Bauhinia it will be taken up and cause problems. I'm not familiar with the other herbicide you mentioned. Other herbicides can definitely move up in rootzones, even those used for selective weed control in turf such as dicamba.

Theoretically these products are not supposed to be uptaken by a plants roots, they are only supposed to be absorbed by the leaves and moved into the roots internally. In reality many so called weed sprays have been shown to also be absored by the non target plants roots and if not kill the plant at least cause problems with growth. If things a mild as 2,4,D can adversly affect a Lilac why would not something stronger adversly affect a larger plant?

Hey, I'm having a similar problem - sprayed Ortho Weed Be Gone Max around my Japanese red Maple that I planted last spring. I sprayed the area ~ 8 days ago & the next day, the leaves on the bottom of the maple became dark maroon & curled in on themselves, and the whole tree became rather 'sad and droopy'. I don't know if I killed it? It's 4 ft. tall.

missymar,

I responded in your other post -- time will tell.