Issue: June 24, 2000

• Wasps and Hornets in Shed

Wasps and Hornets in Shed

I have a nest of what seem to be (feel like) hornets in my shed. How can I positively identify them and what should I do about them? George Chandler Corrales

Hornets are a possibility, as are wasps (paper wasps who make their nest from a paper-like material). If you want to identify them, you will need to collect a dead example and take it to your local Cooperative Extension Service office. The Extension Agent should be able to identify it for you or he can send it to the NMSU Extension Entomology Specialist for identification and recommendations.

Getting the sample may be a major trick as I am sure you don't wish to be stung again. Perhaps there is a dead specimen just outside the shed or inside the door where it is safe to collect it. Otherwise, you might wish to use a spray to kill them, and then collect a sample. The hazards when spraying are the same - don't let them sting you!

The hornets and wasps are least active when the temperature is lowest, that is, early in the morning about the time the sun rises. They will be slowest at that time, but since it is summer they may still be capable of flying, chasing, and stinging you.

There are special aerosol wasp and hornet sprays made for the purpose of treating wasp and hornet problems. The aerosol container of insecticide produces a narrow stream that can be directed at a wasp or hornet nest from a relatively great distance (relative to using a fine mist spray which requires that you be quite close to the target). If the wasp (hornet) nest is just above the entry door into the shed, the distance that the spray can be dispensed is not as relevant. The problem here is that a wasp or hornet nest in this location gives you no safe place from which to use the insecticide. If the contents of the shed will allow use of an aerosol insecticide "bomb", then that may be a safer way to treat the problem. Be certain there is no flame or potential for a spark which could ignite the fine mist of insecticide.

A fine mist of dishwashing liquid (about 2 tablespoons/gallon) is often effective at knocking down wasps and bees. This, used with a medium-fine mist from a pesticide sprayer, may allow you to get at wasps and hornets over the entry to the shed.

In any case, plan your escape and be certain that there are no obstructions to running for shelter indoors when they begin to pursue you. It would also be wise to have another person handy in case you have an allergic reaction to any stings and need medical attention. You might want to purchase a "bee suit" (contact some of the pesticide distributors), or you may find it easiest and safest to hire a professional pest control operator (exterminator). This last suggestion is definitely the safest for you. Be certain the exterminator is reputable, licensed, and insured.

Finally, remember that wasps and hornets have some beneficial characteristics. They eat other insects which are pests in our landscapes. However, even though it is beneficial, it can be painful and even dangerous to be stung by these insects.

Last year I burned a lot of plants using a spray-on fertilizer in the summer. Is there something organic that I can use without hurting my plants?

In defense of the spray-on fertilizers, a lot of people use them effectively. It is important to be careful not to make the concentration too strong and to apply them in the early morning while the temperatures are cool and evaporation minimized. The plants should be well-watered when these materials are applied.

To specifically answer your question: Yes, there are "organic" spray-on treatments. You can purchase fish emulsion fertilizer and, after diluting it according to the directions, apply it to your plants. You can also make compost tea or manure tea by soaking compost or manure in water until the water takes on the brown color of the compost or manure. This may also be sprayed over the plants. Don't make them too concentrated and, as with the commercial spray-on fertilizers, apply them early in the morning to well-watered plants. -->

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!