Beneficial Pests

Beneficial Pests. I’m Greg Martin with today’s Line On Agriculture.

Creepy crawlies. A topic ripe for a Halloween story but in this instance it’s more a case of good news. Yes, I admit I’m not found of insects crawling around in my home but in most cases I will go out of my way to remove the critters to the great out doors where they can get on with their business. Agriculture has been dealing with the ups and downs of little critters for years but as any good gardener knows, there are some good insects out there. Researcher Bob Pfannenstiel says true to form though, nighttime is the fright time.

PFANNENSTIEL: One of the things we find is that in some locations predation is much higher at night. The predators that are active at night and that are causing this mortality to our pests are not necessarily things we would have expected. Our goal is to identify what predator might be important and then look at ways we can augment them in these cropping systems.

One instance that Pfannenstiel noted involved one of the creepiest insects out there, the cockroach.

PFANNENSTIEL: I started noticing a cockroach feeding on these moth eggs and at the same time in the field around me at night the population of these cockroaches was increasing exponentially to the point where this field had hundreds of thousands of these cockroaches.

The roaches were eliminating a soy bean pest. Another one of my least favorite crawlies are spiders. But again there are a number of them that are quite helpful.

PFANNENSTIEL: There’s a group of cursorial spiders, these are spiders that run up and down the plants all night long, they don’t hunt with a web, and these spiders are very important predators of lepidopteron eggs, essentially baby caterpillars so we found that these spiders were important and these spiders have never really been studied.

Mostly because we tend to stay out of fields at night when not only spiders but other monsters are out lurking around. He says they have found that a number of these predators also thrive on the nectar of certain plants which helps increase their numbers.

PFANNENSTIEL: With that discovery several years ago we are looking at developing nutrient sprays to put out into crops that either do not have these nectars and try to hold essentially the small spiders that balloon in the crop early in the year when they might not be able to find prey and then give us some augmented control of whatever pests we happen to be dealing with.

That’s today’s Line On Agriculture. I’m Greg Martin on the Northwest Ag Information Network.