The Ground Beetle: Weed Seed Predator

[Badass beetle photo credit: Nick Sloff of Penn State]

In the comments section of my last youtube video (because I have the best comments section on YouTube) someone posted an article about seed predators and I couldn’t resist.

Essentially, it details how different types of macro (insects, birds, rodents), but also micro (fungi) organisms consume weed seed, and almost exclusively weed seed. Obviously, there is some amount of crossover, but as the article states “While some weed seed consumers will also take crop seeds, many appear to be sufficiently selective to qualify as predominantly beneficial organisms unlikely to hurt crop establishment or yield.”

And, of course, how do you promote more of these? “Weed seed predators require suitable conservation and habitat protection in order to remain active in crop fields. Broad spectrum insecticides are likely to wipe out ground beetles and other seed-eating insects. Frequent tillage disrupts ground beetle habitat, and any tillage that inverts or deeply mixes the soil buries weed seeds out of reach of most predators. Seed predators prefer habitat that includes at least some ground cover—organic mulch and/or living vegetation—and ground beetles have shown a clear preference for cover cropped plots over adjacent clean-cultivated plots (Shearin et al, 2008).”

Not only do ground beetles consume weed seed, they are also veracious predators of pests like cabbage loopers and aphids. Check out the article, it’s not too long and definitely worth the read. It’s part of a series at Extention.org, Twelve Steps Toward Ecological Weed Management in Organic Vegetables.