Issue: July 7, 1997

Elm leaf beetles invading new home

I found these insects (sample enclosed) in the new house I bought in Raton. I don't want to use insecticides which are dangerous to pets and my young children. What do your recommend?

The insect samples you sent were elm leaf beetles. While these insects can make elm trees look pretty bad, they usually do very little damage to the health of the trees. The primary problem is that they can become nuisances as they get lost and enter our homes.

Since they cause little actual permanent damage to the trees, we don't normally recommend insecticide applications except for cosmetic purposes and to protect a tree which is at risk due to other problems. Insecticides which may be used include Sevin(TM) or Bacillus thurengiensis var. San Diego. The Bacillus thurengiensis (B.t. San Diego strain) is a toxin made by bacteria. This toxin has little effect on people, birds, pets, or even other insects. It is specific for beetle larvae. It does not persist long in the environment and may need to be reapplied frequently.

Insecticide application will probably not solve your problem since the real problem is indoors. Spraying the trees around your home will be of little benefit because there are so many other elm trees in Raton which are not treated. You will still see invasions of these lost insects. The best solution for you is to improve the weatherstripping around your home, make sure window screens fit tightly, and seal any point of access from outdoors to the inside of the house, attic, or crawl space; or, close access from the attic and crawl space to the living space in the home. Ceiling light fixtures, electrical outlets, and pipe runs into the house are points of insect entry. By caulking, or otherwise sealing these entry points, you can reduce, but probably never eliminate, the problem. For those insects which still manage to sneak past all your protective measures, the only recourse is to vacuum them and discard the contents of the vacuum bag. Remember, don't empty the vacuum bag into the garbage inside; the insects will find their way out of the garbage and into your living quarters.

You can also get pest control information as well as information about many other topics from your local County Extension Office.

Waterlogged African violet

I have a beautiful African Violet in my home. Recently went on a vacation for about 45 days. While I was gone, I had a friend come in and water my plants. I believe she was a bit over zealous with the water. My violet was soaked, completely. I immediately transplanted my violet, and when I did, the old pot was a mess of runny mud. I now have my violet in a new pot, and she seems to be doing better, but some of her leaves are turning brown and are soft and mushy in the middle. Should I just leave them or would it be better to trim them?

I would remove the leaves that appear damaged. How does the base of the plant (the crown) look. As long as it is healthy and the leaves are not dying from the point where the petioles attach to the crown, I wouldn't worry too much.

Be sure to water carefully. There may have been some suffocation of the roots and you do not want to make that worse or to have root and crown rot begin. Water enough to keep the plants from wilting, but do not keep the soil too wet. I assume you have been caring for the African violet for a while and have a good idea regarding watering.

If you are concerned that there is a rot problem beginning, check with your local Cooperative Extension Office or a local nursery. They may be able to advise you of fungicides or other products labeled for use on African violets.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!