Glue-banding of tree trunks is an effective technique for controlling various pests of fruit trees. A waterproof band covered in horticultural glue, an aggressive long-lasting adhesive, is wrapped around the trunk of the tree to create a sticky barrier which prevents climbing insects from making their way into the tree canopy to feed, mate, and lay eggs. Glue barriers are also a useful way to keep ants away from hummingbird feeders without harming wildlife.
The use of horticultural glues is recognized as an effective pest control method in organic gardening, and is used to deny pests access to trees without the use of harmful chemical pesticides.
Which Pests Can Be Controlled?
The following pests can be controlled with glue-banding:
- codling moths
- elm leaf beetles
- gypsy moths
- procession caterpillars
- spotted lanternflies
- tent caterpillars
- winter moths
Please note that some of the pests listed above may be specific to certain locations around the world only, while other may be more widespread or universal in their occurrence
It’s important to point out that the reason ants may need to be controlled is because they ‘farm’ sap-sucking pests such as aphids, scale and mealy bugs to provide ant colonies with honeydew, which they use as a food source. Ants will shelter these pests in their underground colonies in winter, then carry them up into the tree canopies in springtime and strategically place them on new growth. When these pests suck the sap of the tree, they excrete a sugary liquid, termed ‘honeydew’ which the ants harvest. Since these pests are valuable to the ant colonies, the ants will protect them from predators such as beneficial predatory insects.
Glue-banding can make all the difference in respect to whether pest populations survive or perish. In a Japanese study of how ants manage aphid herds on mugwort plants (“Color polymorphism in an aphid is maintained by attending ants” by Saori Watanabe, Taiga Murakami, Jin Yoshimura and Eisuke Hasegawa), it was found that when the stems of the mugwort plants were protected with horticultural glue to deny the ants access, the aphid populations soon became extinct due to the action of predators, an indication of how effective the natural controls are. When the ants aren’t able to protect the pests, the beneficial insects such as parasitic wasps, ladybirds, lacewings and hoverflies get rid of them up much more quickly and easily.
Looking at the list of pests which can be controlled by glue-banding, it may be apparent that some are flying insects rather than climbing insects.
You may be wondering how glue-band barriers stop flying insects such as moths? By understanding the nature and habits of pests we are better placed to control them. Moths have four stages in their life cycle – adults lay eggs which turn to caterpillars, the caterpillars pupate in their cocoons and drop into the soil where they overwinter, emerging when the soil warms up in spring. When they first emerge they don’t fly freely, they tend to climb up the trunk of the tree flapping their wings, which is why the barrier is effective against them. Additionally, if any caterpillars fall from the tree canopy, they wont be able to get back up, and if they decide to move from an unprotected tree to a protected one for more favourable conditions their journey will be halted.
Weevils are a type of beetle, and even though they have wings, many adult weevils do not fly, and so can be stopped by the use of glue bands on tree trunks.
How to Glue Band a Tree Trunk
Horticultural glues are they key component of a glue band barrier, they are a very sticky, non-drying, waterproof and that remain effective over a long time. The are sold under various product names, such as Tanglefoot in the US, Trappit in the UK, Tree Guard in Australia.
You can also purchase ready-to-use products such as the On-Guard Fruit Tree Grease Band which comes on a roll and is easy to cut and fit.This product is fastened 45cm above the soil level, and tied in place with the provided fastening material.
Horticultural glues are never applied directly onto the bark of a tree, as trees with thin bark, especially young trees and citrus trees can be sensitive to direct glue application. If the tree bark gets damaged right around its circumference, the tree will be ring-barked and die! Furthermore, the glue makes a sticky mess once it’s covered with insects. Always apply a protective banding material around the tree trunk first, then apply a layer of horticultural glue onto that, this way it’s removable and replaceable.
Tanglefoot make a tree banding product Tangle Guard, which looks like a very thin cardboard-like material, The manufacturer recommends wrapping the band 1.5m (5’) above the ground (if your tree trunks are that tall! – I recommend 45cm or 1.5’), overlapping it 1.25cm (1/2”), then fastening with duct tape and applying the horticultural glue over the banding.
Banding materials are oil resistant, as this prevents them soaking up the glue, which means less glue is needed, and the glue stays sticky for longer. They are also waterproof and rot-proof for obvious reasons, they need to last for a while outside in the elements.
You can make your own banding materials from duct-tape, masking tape or electricians tape, use the widest tape you can buy, if it’s close to 7cm (3”) wide, that’s ideal. Unlike the way most people do it, I recommend wrapping the tape with the sticky side OUTSIDE, not on the tree bark!
Some gardeners use cling-wrap which is used in the kitchen as tree banding, it may require a few layers to get a strong surface that doesn’t tear when applying the glue layer. Pallet Shrink Wrap, which is a much heavier duty wrapping plastic could possibly work also.
Where to Band a Tree Trunk
Banding trees at 45-50cm (approx 1.5’) above the ground is a good practical height as most backyard trees are pruned so the trunks are between 60cm-100cm )2’-3’) tall when they’re purchased from a garden nursery.
Some of the horticultural glue manufacturers recommend banding trees around 1.2-1.5m (4’-5’) above the ground, that would only be relevant to very tall trees whose trunks are very tall and branching begins at a height much higher than the banding height.
Before applying tree bands to tree trunks, make sure that there aren’t any low hanging branches touching nearby plants which pests can use as an alternative path to get around the glue barriers to get into the trees.
If the tree bark is rough or has cracks and crevices, it’s often recommended to use cotton balls to close up big gaps to stop insects getting underneath the tree banding material.
Applying the Tree Banding
How to glue band a tree using adhesive tape:
- Place the smooth non-sticky side of the tape against the tree bark
- Stretch the tape around the tree trunk with the sticky side on the outside (not on the tree bark side), then overlap it around 10cm (4”) to secure it in place, then cut.
- Fold over the top corner to create a small tab to make it easier to peel the tape off when it needs to be replaced.
- Using a disposable spatula, icy-pole stick or putty knife spread a wide band of horticultural glue around 10cm (3") wide over the banding material.
- When the tree band is covered in insects or is no longer sticky, remove and replace.
- Remove tape at the end of the pest season to avoid girdling the tree and restricting its growth
When to Apply Glue-Banding
Timing of tree banding will vary with location and pest being controlled. Many pests emerge in spring, such as ants and codling moths, whereas other pests may be active in autumn, such as fall cankerworms. It’s best to place banding on the trees before the season of pest activity, such as late winter for springtime pests, so the controls are in place before the pests emerge.
What about Elm Leaf Beetle?
Glue banding will work on elm leaf beetles because their larvae (grubs) need to crawl down the tree to pupate near ground level. This happens between December and early February in Australia (summer) depending on weather. By placing a wide band around 20cm (8") wide made of sticky-side-outward facing adhesive tape around the tree trunk (spiral several overlapping layers around the tree trunk to make up the required width), the larvae will be caught, breaking their life cycle. Spreading the horticultural glue over the tape will be more effective but apparently the sticky side of the tape will work reasonable well on its own. The larvae that fall out of the tree canopy won’t be caught, but the rest will.