Oops, no worms!

September 2015

Photo Creative Commons

Earlier this year, we reported an Argentinean experiment in which a commonly-tested earthworm species was annihilated by a single spray of glyphosate herbicide [1]. Now an Austrian team have added data on two other earthworm species which fully support the self-same disaster-scenario.

Earthworms are vital to sustainable soil fertility. Up to 1000 individuals in each square meter of land act as ecosystem engineers: they shred plant litter and process it in their gut making nutrients available to plants; their burrowing aerates the soil and enhances water- and root-penetration.

Chemicals which harm the worms in soil are bad news.

Although it's heavily used on GM crops because most have been transformed to tolerate it, the very idea that glyphosate herbicide (active ingredient of 'Roundup') could be detrimental to earthworms has barely been entertained. After all, this chemical interferes with a biochemical pathway found only in plants, and the plant litter generated by the dying weeds will provide extra food for the worms. Glyphosate is obviously safe for animals, and obviously has benefits for nature.

Or does it?

Science says otherwise.