Insects - Bagworms; Tent Caterpillars; Fall Webworms
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  (January) I have a Flowering Cherry Tree that we planted three years ago. We planted in the spring and that first year caterpillars stripped off every leaf and it stood bare for the rest of the season. The second spring caterpillars again came, but as soon as I noticed a few munched leaves I wrapped aluminum foil around the base and lathered it with Vaseline. This worked to keep the caterpillars away, but when I removed the foil in the Fall the trunk looked terrible. The trunk healed and the tree is healthy, but Spring is coming again. What should I do to keep the caterpillars away?

  It sounds to me like you have the eastern tent caterpillars. They often have their preferred tree hosts, and try to visit annually. Using the preventative barrier is a good idea, but remove it in June. Instead of aluminum foil, why not try either a tree wrap or even plastic wrap coated in Vaseline, or similar sticky substance, wrapped in a small band near the base of the tree. The foil would attract extra heat. The eastern tent caterpillars are one of those "here today, gone tomorrow" type of insects. They seem to be the plague of locusts for awhile, but are relatively short lived. They are quite the nuisance while they are here.

  (July) I need your help quickly. I have a cedar bush that has just gradually died, so I am beginning to cut it down. As I was lopping off limbs, I noticed these little pods that were moving and looked closer and the pods have little worms in them! A friend told me they were bag worms. Is that correct? Now, they are all over the ground. Will they infect my other bushes and trees? And how do I get rid of them. How do I dispose of the limbs I cut and the stump when I can get it pulled up? I’ve never seen anything like this before

  You do have a problem with bagworms. These insects usually begin feeding around mid May and are done with their feeding by mid to late June. By then, they have constructed the sacs or bags made of the host plant. These bags protect them from predators and insecticides. Spraying now is not very effective, and I do not think they will have time to move to other plants in your garden. They tend to prefer conifers—cedars and junipers in particular. Usually a first time attack won't kill a large established plant, but it can do some damage. This late in the season, hand-pick and destroy the insects, preventing them from completing their life cycle, and hopefully reducing your chances of problems next year. If you have plants which repeatedly get attacked, you can spray weekly with BT or liquid Sevin from mid May through mid June. They should not be on the old stump, but do dispose of the plant debris.

  (August) I have a problem with sack worms (don't know proper name) in my trees. I know they can be burned out, but these are too high to reach. Is there any other way to eliminate them. I understand they will kill the trees eventually.

  There are several insects that you could be referring to -- Eastern Tent Caterpillars which are now gone for the season but still have the remaining ugly webs, or Fall Webworms, which we have now and will have a couple of generations of. Both of these insects form large, unsightly webs in the trees. They can attack a wide range of trees, but prefer certain species, and often return annually to the same trees. The messy webs and large volumes of larvae cause concern, but their "bark is usually worse than their bite". They are unsightly but rarely do any major damage for a large tree. If you can reach the web, pull them out and dispose of them. Otherwise I would try not to worry. The other possible insect you could be referring to is a bagworm--the type that forms an individual sack or bag around themselves. They feed primarily on needle type plants such as junipers and cedars, and construct their sacks as they feed. By now the damage is pretty well done. You can handpick and destroy. Spraying the plants with Sevin or BT next May and June will kill them before they do damage. Since you mentioned the insects were up high, I believe it is one of my first two possibilities. While sprays can be effective, timing and thorough coverage is important, and if they are up high that is hard to do.

  (August) I caught your article in the Arkansas Democrat Gazette about bagworms, but I didn't catch when exactly to spray, and what to spray. I have just noticed bagworms on my large cedar trees, which are about 8 years old. The plants seem to be covered with them. What and when do I spray them? I really don't want to lose them. Thanks again.

  Spraying now is ineffective, since they are protected by the bag. Try to pick off as many as possible this fall. Sprays are effective next year as they begin to emerge and feed. For best results, spray weekly from early May until early to mid June with an organic spray of BT, Thuricide or Dipel, or with a non -organic Sevin.

  Are the fuzzy caterpillars that appear to be everywhere, officially known as tent caterpillars? That seems to be the closest definition we can find in our encyclopedia. At any rate, one of our trees had an infestation, which we attempted to destroy, but it seems like many of the worms survived. What is the best means to destroy these pests and discourage their return? Any suggestions would be appreciated.

  We have two types of caterpillars that make large webs in our trees. In the spring, they are eastern tent caterpillars and in the summer and fall, it is fall webworms. The tent caterpillars are really more of a nuisance than deadly. They usually leave their webs to eat during the day, congregating back into their webs at night, or during rainy weather. Spraying the surrounding foliage with dipel, thuricide or BT can help control them, or try to get rid of the entire web when they are inside it by pulling it out of the tree, if you can reach it.

  I am getting overrun by bagworms. They are fuzzy caterpillars and they have made obnoxious bags in my tree. I think they are going to eat my plants alive. What can I do to control them before they destroy everything?

  Eastern tent caterpillars are a nuisance every year, and this year is no exception. Although they look bad and seem to be everywhere, they really aren’t that much of a problem. They are relatively short-lived. If you can pull the webs down during cloudy days, or in the evening, when they are clustered in their webs, you can destroy them easily. Be patient, and they should soon be gone.

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