Colorado Potato Beetle in Las Vegas? Maybe, Maybe Not.

Q. I've just spotted Colorado potato beetle bugs and larvae on my tomatillo plants. I didn't even know what they were until I did some research. I've never seen them out here before. I can't find an organic pesticide that will kill them without hurting the bees and other beneficial insects. Do you have any advice for me?

A. Make sure it is actually the Colorado potato beetle and not a look-alike insect called the Ten-Lined June Beetle. I have not seen the Colorado potato beetle in the Las Vegas area yet but it is possible. Until recently, Nevada was one of four US states that didn’t have this pest.

Ten-Lined June Beetle

            But I have seen the Ten Lined June beetle here and they look very similar to the Colorado potato beetle. I posted a picture of this critter on my blog. The safest way is to pick them off as you see them. In small garden plots this works well. You can also use a cordless vacuum cleaner and suck them up that way.

 

            As far as sprays go an organic/biological pesticide called Spinosad, which is available in many nurseries now, will give some control.

Colorado potato beetle adult (striped) and larvae without stripes on potato leaves in Kosovo.

            Another organic/biological control chemical is Bacillus thuringiensis (Bt) var. San Diego (also called variety tenebrionis) gives some control if they are not resistant. This particular type of Bt controls beetles. But this organic spray is hard to find locally. You will probably find it only online.

 

            There are Bt sprays in the nurseries but this is the wrong Bt spray for Colorado Potato Beetle. The one in the nurseries is Bt var. kurstaki (Btk). This Bt is used to control larvae or caterpillars that form moths and butterflies like the tomato fruit worm, tomato hornworm and grape leaf skeletonizer.