January 10, 2015

1 - In mid-winter plant related insect pests may need management indoors, but do so carefully.

Q.

I have noticed some very small, fast moving insects in my kitchen. I do not have any fruit out and they seem not to be attracted to the garbage, so I do not think they are fruit flies. They are attracted to the outside of white cups, but will not go into vinegar and soap traps that my daughter suggested. I have tried to catch them with sticky tape, but when I get close to them, they fly away in the blink of an eye. What is this and what can I do?

A.

Without seeing the insects, it is impossible to be sure what pest you have, but I can make some suggestions. A common indoor nuisance pest is the fungus gnat that reproduces in the potting soil of potted plants. Their larvae feed on fungus in the soil and to some extent on the roots of house plants. The damage they do is minimal, but they are attracted to lights, computer and TV screens, and windows. There are pest control products in some garden stores containing materials safe to use indoors that you might want to use to treat the soil of potted plants. You may need to repeat treatments periodically in accordance with the directions on the product if you choose to use such a product. If you do use these, be sure to choose one of the products safe for use on indoor plants. This should reduce their reproduction, but will not remove the adults flying around now. They will eventually die, but you can reduce the number of insects using yellow sticky traps. Such traps are available as some local garden stores and on the internet. You may also make your own by taking a bright yellow plastic container, such as those in which you purchase some food products, coat the container with shortening or sticky oil. Place this on a window sill where the light strikes it or in a location where it is lit by a bright light to attract the insects. Once you trap some insects in this manner, you can take some samples to your local NMSU Cooperative Extension Service office to have the insects positively identified. This will help with proper treatment.

Some indoor plants may be harboring aphid insects. These may often be treated successfully by spray applications of insecticidal soaps which are generally safe for indoor use (protect carpets, draperies, and upholstery). The sticky traps may also be useful in this case.

Another indoor nuisance pest that may be the culprit is the drain fly. This is a very small, true fly. It breeds in the drains of sinks and bath tubs. They may feed on hair balls and other debris trapped in the drain. Pouring some chlorine bleach down the drain and removing as much debris as possible may help reduce the problem. The sticky traps should also be effective for this insect. Trapping will again allow your local NMSU Extension Service to positively identify the pest to determine the best possible treatment.


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.

Links:

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

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

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