I have seen some moths around town lately and received calls about the number of moths locally. Some caterpillars over winter and others migrate north as moths.
The moths this year will probably be either a cutworm or armyworm of some type. The life cycle of the moths is around 10-14 days. That is the good news! The bad news is they can have up to three generations a year. Also, each moth can lay between 500 to 1,000 eggs so there is some potential to have more moths later this summer.
The problem with trying to control an adult insect is frustrating for two reasons. One being that it is highly mobile and secondly it takes quite a bit more insecticide to work on adults than immature insects. This is why we recommend controlling the immature insects so we do not have to try to deal with the adults.
In controlling these insects, you should try to use preventative measures first, then resort to spraying later. One thing you could try is putting a light in your yard if you do not have one and placing a pan of soapy water under it. This should catch some of the moths. Also try closing your curtains early in the evening so as not to have the moths attracted to your inside lights. Electric bug zappers might offer some relief also.
If these types of measures do not work, then try one of the following controls. Bacillus thuringiensis: this is a bacterium that will eventually kill the caterpillars but it will not work on the adult moths. Insecticidal soap may offer some help but it is only a contact insecticide. Pyrethrum is a general insecticide that is a safe chemical. This can come in sprays, foggers and liquid. Vapona — (DDVP) I have seen this in an aerosol spray and should work around the home. The biggest problem is that these control measures are only temporary since other adults can fly in tomorrow and start things all over again. And, the material has to be sprayed directly on the insect. Robins and other birds will eat some of the moths, so at least the birds appreciate having the moths around.
Did you know that 90 percent of the insects around your home are beneficial to or do not harm your plants? They eat pest insects, recycle organic debris, or feed on plants without causing any noticeable damage. Always try to use the least toxic means of control first so as not to eliminate our beneficial insects.
Insects of all kinds will probably be a concern this year with the cool, wet weather, including mosquitoes. Therefore, it will be important to check your plants regularly for insects and control them before the pest population explodes out of control. There are some very good chemicals available for gardens and yards and for those who would like to use an organic approach those products are also available at most retail garden stores. Also keep an eye out on evergreens again this year for borers. Some just leave holes and others will have sap coming out of the holes.
Now is also the time to be checking for spidermites.
Cool wet weather can negatively affect vegetables; stunting them or promoting diseases. Keep a watchful eye on your plants for diseases or other health issues and treat early.
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Scott Hininger is with the Sheridan County Extension office.