What time of year is best for getting rid of bittersweet vine?
Is November in Massachusetts too late to cut the trunk of bittersweet vines and apply Roundup to eradicate this menace? There are vines going almost 100 feet high in a pine tree. How can I get rid of that specific vine?
Middlesex County Massachusetts
While you can cut the trunks at any time, you want to apply Roundup or Brush Be Gone or another herbicide to the trunks when the plant is actively growing. Actively growing plants are taking up food and nutrients from the soil and transporting them up to the stems and leaves and at the same time the food made in the leaves by photosynthesis is being sent down into the roots.
So while you may get some translocation of the herbicide applied to the stems if this warm weather continues, it probably will not be enough to kill a large plant. So I would wait until the plant starts to leaf out in the spring. Although, if there are some stems of bittersweet that could be cut and yanked out of the pine tree now that would be okay too.
The roots will have enough energy to send up new shoots in the spring and these can later be cut off and herbicide applied to the stems. Often it takes several years of cutting and applying herbicide to defeat these plants.
As for how to get it out of the tree - your options are to let it die and decompose which will take a number of years, see if you can prune out any lower sections with a pole pruner, or talk to a local tree company and get an estimate of removal. This is one reason it is really good to catch a bittersweet invasion early. Take into account how much bittersweet is in the tree and whether this might cause problems during heavy snows and ice storms.