Insects - Caterpillars
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  (April) We moved into this home last April and the entire season our Holly bushes had holes eaten in the leaves. I would sometimes see leaves hanging on by a web. A few limbs were dead, and pulled out easily, but mainly there were holes in the leaves. I'm not sure what type of Holly this is, or if it is a boxwood. It has red berries on it in the fall. I am in desperate need of a plan for getting rid of the pests and also advise on getting the size under control. Do you have any tips on pruning it? It is way up over the roof of our house and looking bad right now.

  If you have red berries, you probably have a holly, not a boxwood. Chewing insects that eat large holes are usually caterpillars or some type of beetle or grasshopper, and although they make the plant look less attractive, rarely will they kill an established shrub. Usually you can see them. For chewing insects you can use Sevin or similar insecticide. If it is caterpillars, you can use BT, or bacillus thurengiensis. I would not use a preventative insecticide, but I would monitor for problems, and spray if you see new damage this growing season. They can be pruned now as much as needed. Severe pruning may prevent berries for a season, but they should recover.

  (May) I have planted zinnias in a "butterfly flower bed." Something is eating them up and because they are in a bed I want to bring butterflies to, I don't want to use an insecticide on them. What can I do?

  If you aren't sure what is eating your zinnias, it is quite possible that it is some small caterpillar. Anything that would kill a chewing insect, would also kill any caterpillars -- the precursor to the butterfly. For now, simply live with the damage, and see if you can investigate to find out what the culprit is.

  (June) I have just harvested my first cabbage and it is pretty wormy. I refrained from applying any insecticide to it while it was growing because it seems to me the poison just gets worked into and imbedded in the leaves and because we prefer not to use poisons if they can be avoided.

Is there an alternative to Sevin dust? Is my assumption that the poison will get imbedded in all those convolutions correct or does the cabbage grow from the inside out in such a manner that that is not an issue?

  If you apply pesticides at the recommended levels and follow label directions, you should be fine in using them. If you prefer to go organic, for cabbage worms, there is an organic insecticide called Bacillus thuringiensis. It is sold under the trade names of Dipel, Thuricide and BT. This is totally safe, and only hurts caterpillars -- no beneficials or others.

  (July) I live in Warren, and we have many hardy hibiscus and Texas star hibiscus. They are both infested with some insect which strips the leaves, leaving only the veins. They are continuing to bloom as if nothing had happened. I have noticed many small black flying insects which have an orange spot on their back. Are they the culprits, and how could I kill whatever the offenders? My tropical hibiscus plants are not bothered this way.

  There is both a beetle and a caterpillar that can do a number on hardy hibiscus plants. While it does make the plants look less than appealing, it really does little to damage their hardiness. If the damage is so bad that you can't live with it, there are several remedies to try. It sounds to me like you have the beetle problem--sprays with liquid sevin or permethrin can help. You can also use the systemic Bayer Advanced Tree & Shrub insecticide as the plants begin growing next spring. For those with the caterpillar problem, you can also use Bacillus thuringiensis or BT, Dipel or Thuricide. Whatever pesticide you use, opt for one that mixes with water, I would avoid the dusts, since that also can take away from the aesthetics. If you are using the plants to attract butterflies, then avoid the insecticides and live with the lacelike leaves-tell people that's the look you were going for!

  (October) I planted Egyptian Starflowers in large pots on my front porch last spring and they have done beautifully. This week one of them was inundated with those horrific and huge green or sometimes brown thick caterpillars that plague tomato plants. The plant was 75% eaten in just a few hours. I pulled them off (yuck) and put Sevin dust on both plants. They seem to be okay now. What would you recommend I do next year to avoid this problem? These were the perfect flowering plant for this location (western exposure) so I'd like to use them again. Any advice you can give would be appreciated.

  Hopefully the caterpillars were a one time problem. Did you recently pull up your tomato plants? Often we see a pest move into new territory when their favorite host is gone. I would not recommend a spray program for Egyptian Starflower (Penta). They are pretty durable plants, and one of my favorite for full sun. If you see the pest beginning again in the future, handpick the big ones -- the larger they are the harder they are to kill. You can use Sevin, but I would prefer a liquid or wettable powder to avoid the white dusty appearance. You can also use an organic product called BT, Dipel or Thuricide.

  I have looked all over Hot Springs for an organic pesticide called "BT". I have not been able to find any of it. It is supposed to be very good in controlling caterpillars. I would like to try it, as I have a lot of trouble with these pests.

  BT is actually Bacillus thuringiensis. It is an organic insecticide that is specific to certain insects, depending on which compound you get. The one that is specific to caterpillars is sold under a variety of trade names, including: BT, Thuricide or Dipel. Most nurseries should have some form of it.

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