by Sandy Garland

Once upon a time, 4-5 years ago, I pulled out the DSV that was growing under this walnut tree. I put down some newspapers to keep it from growing back (this doesn’t really work) and forgot about it. This year, I noticed there is almost no DSV under this tree. The few DSV plants there are small and wilted.

Another walnut tree, about the same age as the previous one, but this one has been ignored and is surrounded by DSV. A new volunteer has undertaken the job of pulling out this DSV in hopes of duplicating the experience just described, i.e., hoping the tree will inhibit regrowth of DSV.

Under it, inside the “drip line,” there is no DSV and, in fact some bare spots where nothing is growing.

An area that was sprayed with Roundup last summer and again this spring. DSV is yellow and wilted, but most other vegetation has also been killed.
A closer look at a DSV-free area next to the large walnut tree.
Very intriguing Sandy. Wouldnt it be wonderful if the juglone in the walnut trees could actually inhibit the growth of DSV. Congrats to you and your volunteers for continuing to work on the control of this monstor plant!
ClaudiaBurns
This is quite interesting and worth experimenting with! Should I husk any black walnuts this year I will take some to our local community orchard in Heron Park and draw a “line in the sand” to see if the juglone may hinder the invading front of DSV, yet allow grass & some other plants to grow.
Thanks for the feedback, Claudia and J. Garlough!! Gosh, yes. If anyone is experimenting with walnuts, please share your results. That said, we tried a similar experiment at the FWG. I gathered a bunch of walnut hulls (the fleshy part that surrounds the actual nut) last winter and tried burying them in a bunch of DSV this spring. I couldn’t see any difference, but probably because there were too many other things going on – like trampling the DSV while trying to bury the walnuts. I’m contemplating trying again, but this time with DSV in pots where I can keep an eye on it.
I wondered if there would happen to be any updates to this experimentation with using walnut trees to discourage DSV?