Product Used: Roundup® Poison Ivy & Tough Brush Killer Plus
I have a hill side approximately 20' x 50' filled with thorn vines
approximately 6 to 10 feet tall. I sprayed each vine from top to
bottom with Roundup® Poison Ivy & Tough Brush Killer Plus Concentrate
yesterday and again this morning. This morning I noticed the vines are
turning dark brown. (I hope that's a promising sign that they are
-How long will it take for the vines to die completely? I would like to
clear the hill side as soon as possible (definitely before it gets to
-Will the thorn vines return this year or next year?
-Can I plant a ground cover in the same area. I am considering low
growing drought tolerant --possibly phlox. I am eager to through seeds
in the area next month.
ps. This is a long weekend for yard and garden projects, i.e.,
spraying the vines again or removing the vines from the hill side.
Some thorn vines can be *extremely tough.* However, I have used Roundup
(very carefully and selectively) for many years, usually with good results.
The head of the grounds crew at the local university told me several years
ago that it is actually better to use Roundup at a slightly *lower* rate
than what is listed on the bottle (whereas most people want to increase the
proportion). He also said that the plants sprayed will be "dead" after 9-12
hours, even though they will not look like it. Roundup is a systemic, and
it will have entered the root system by that time.
I am actually a little concerned that your plants look brown after such a
short time. It sounds like your application may have been too heavy.
First, Roundup needs for the plants to be actively growing for it to
effectively kill them. If the vines are still dormant, it may take
another application. If you try to kill weeds in early Spring or late
fall it's far less effective than if you use it when the weather is
warm and the weeds active.
You can reseed a week after using regular Roundup. Not sure what is
added to the Plus concentrate, so I'd check the label or website.
If applied right, you should be rid of the vines without them
reappearing, but it's always possible a small amount could require