Bag Worms & Evergreen Tree

Our Evergreen tree by our garage is/has been attched by bag worms. How do we get rid of them before they totally kill our tree?

 

A quick search on Google using the term 'bagworms' brought up this great information: http://www.uky.edu/Agriculture/Entomology/entfacts/trees/ef440.htm



Neil Z.
Resident since 1999

 

Oh! So that's what those creatures are! I was wondering if I should worry about them.



Pam D.

 

Generally we look to reduce the number of chemicals that eventually end up in our water system so spraying or dusting is not recommended.
Picking the bags off by hand and disposing of them is a much more effective control method anyway as the bags are almost impervious to chemicals and only those worms who have exposed themselves or just hatched actually get hit by the chemical.

So get a pair of gloves and get picking! Be careful not to pull off the bag and leave the worm. Grasp the entire thing at the threadlike base and pull gently. Some prefer to "cut" the silk attachment but I find it doesn't make a difference either way.

Once you get the worms off your tree drown them in soapy water, crush them or put them in a sealable vessel (like a coffe can with lid) and let them bake. If you just throw them on the ground the eggs will still hatch and you'll have the problem all over again.

Keep an eye on your trees. Now you know which ones are vulnerable to attack. Even if you pick off all the bags you see there still may be small newly hatched worms you don't catch the first time around. Be sure to check back about a week later.

Bag worms will usually attach to evergreens but can be found on decidous trees. The bag looks a little different because the leaves are a different shape but they house the same destructive insect.
To read the article from the February newsletter go to http://www.hoa.broadlands.org/newsletter/2005/02.pdf or see next post below.

 

February 2005 Broadlands newsletter article on bagworms is reprinted below:


Check for Bagworms

Check your trees (both deciduous and evergreen) for bag worms. These nasty critters are difficult to spot because they camouflage their skins with the leaves and bark debris of the trees and shrubs they inhabit. Bagworms overwinter as eggs within bags fastened to twigs. Infestations often go unnoticed because people mistake the protective bags for pine cones or other plant structures.

But these insect larvae will be deadly to their host plants when the weather warms up and nearly 1000 eggs hatch from the bag and begin feeding! Bagworms feed on the foliage of a wide variety of trees and shrubs, but are of the most concern on evergreens. Common evergreen hosts include juniper, arborvitae, pine and spruce. Heavy infestations are capable of completely defoliating a tree or shrub, which may be severely stressed or even killed if the control measures are not taken. Less severe injury will slow growth and stunt plants. Bagworms are especially damaging to conifers because destroyed foliage is not regenerated.

Bagworms also feed on deciduous shade, orchard, and forest trees, as well as many ornamental shrubs, but heavy infestations are unusual. Further, since deciduous plants can grow new leaves, damage is usually not serious. The growth of small or newly planted trees, however, can be slowed by bagworm feeding.

Bagworm infestations on smaller trees and shrubs can be controlled by picking the bags off by hand and disposing of them. This approach is most effective during fall, winter or early spring before the eggs have hatched. Destroy bags by crushing or immersing in soapy water. If bags containing larvae are discarded on the ground, the larvae may return to host plants.

The bag-like shell of this insect is all but impervious to chemicals. Insecticides only work on smaller bagworms.

Many trees and shrubs in our area have been found to carry this damaging insect. Check yours (or have the gardener do it) before they destroy your landscape."

 

a true story:

A friend of ours found several bagworms on a tree and so he plucked them off and casually threw them into a plastic bag. He then threw the plastic bag into his trash can. The next day, he found that the bagworms had crawled out of the holes in the bag, climbed up the inside of the trash can and had "glued themselves" all over the inside of the trash can. No amount of shaking and yelling at the can could dislodge the bagworms. They wouldn't come off. So, he had to reach deep into his trash can and literally scrape each bagworm off the inside of his trash can and re-dispose of the bagworms again! This time, he drowned them in soapy water first. Sorry, kinda gross, I know, but apparently bagworms are very durable.