Removing Problematic Vines
Air potato is an invasive vine that quickly takes over and can be very hard to remove. Credit: UF/IFAS
What are a gardener's options when it's too late for "right plant, right place?" In dealing with any hard-to-remove plant, it's helpful to know a little about plant physiology, the study of the functions of a plant's tissues and organs.
Every part of a plant needs sugar to survive — the roots, stems, leaves, fruits, and seeds. Some parts, like mature leaves, are capable of producing enough sugar to sustain themselves and others. We call these organs sources, because they provide a source of sugar to the whole plant.
Other parts of the plant use more sugar than they produce; roots, fruits, seeds, and young leaves and shoots fall into this category. We call these organs sinks, because sugar must be sent to them. It doesn't go "down the drain" however. In the case of fruits, seeds, and some specialized roots, the sugar is stored.
To successfully remove a plant in the wrong place, a gardener must remove not only the sources of sugar, but also any sinks that are storing sugar. Below we offer suggestions for removing all parts of a plant. For tips on removing particularly problematic vines, please see our plant list, Invasive Vines of Florida.
Cutting it off at the source: leaves
Cutting off vines at ground level separates the roots from their source of sugar, and the leaves from their source of water. Credit: UF/IFAS
Removing a plant's sources of food is straightforward enough: cut off the vines as close to the root as possible. If there are multiple stems tangled together, cut them off a couple of feet from the ground and then again at ground level; this creates a "window" of empty space and ensures you didn't miss a stem. These are considered mechanical control methods and are among the safest for the surrounding vegetation.
Some vine species also have biological control options — insects or other plant pests that prey on the vines and help keep them in check. One excellent example is air potato, which is partially controlled in Florida by the air potato beetle. Native to Asia, these beetles and their larvae feed and develop only on air potato plants, skeletonizing the leaves but posing no risk to other plant species. This feeding negatively affects the growth of the plant, helping to control its spread.
Whichever control method you choose, do not attempt to pull vines down from their support structures. Whether the support is a tree, fence, trellis, or wall, vines cling tightly. Pulling on the vines can damage the structure itself. Leave the vines to decompose naturally and nature will do the work for you. If decaying vines still cling after a couple of years they will be much easier, and safer, to remove.
Likewise, don't attempt to pull cut vines out of the ground; often they will break off, leaving root and stem tissue to sprout again next season. Read on for suggestions on removing the underground parts of the plant.
Taking care of next year's vines: roots and fruits
Skeletonized air potato leaves.
Some problematic vines come back year after year, making last season's pruning a thankless task. When a plant resprouts, it means we neglected some roots, tubers, and or stolons that were storing sugars. These sinks are the reason many invasive vines, like cat's claw and invasive wisterias, sprout again so easily. Others disperse seeds or, in the case of air potato, aerial bulbils, that grow into new plants each season.
To remove subterranean plant structures, mechanical control methods are often your best option. Dig at the base of the newly cut stem, following it down to the root. Attempt to remove the entire root and all connected structures. Vines that have been growing unchecked for many seasons can have roots and tubers in excess of thirty pounds, though, so this may not be a one-person job.
A less labor-intensive option is to "paint" the freshly cut stem with glyphosate or Garlon. These chemical control methods are sometimes enough to kill the entire underground structure, keeping the plant from resprouting. Avoid spraying as the droplets may drift in the air and damage nearby plants. If the vine sprouts again next season, cut and paint again or start digging. As always, carefully read the label on all chemicals before you buy, use, or store them. Remember: the label is the law.
The good news is that it is possible to eliminate problematic vines from your landscape. The bad news is that it may take a number of seasons, and constant vigilance thereafter. Even if you've eliminated all the mature individuals of a problematic species, birds and wind may bring more seeds to your yard. Scouting early in the growing season is a cultural control method that can help you catch new sprouts before they're well established.
This air potato tuber probably weighed close to thirty pounds. Without destroying this source of food, the vine will resprout year after year. Credit: UF/IFAS
However you choose to control problematic vines, be sure to double-bag and dispose of all invasive plant material in the regular, landfill trash. Do not compost or send it to be composted as you would other yard waste.
For more information about controlling pest plants, visit the University of Florida IPM website. If you have questions about an invasive species, please contact your county Extension office. Finally, contact the UF/IFAS Pesticide Information Office for more information about herbicide safety.