Adam is correct.  The nematodes are native to North America.

Sheilds presented the background on how they came up with the nematode solution at one of our pesticide points meetings.

The short version,,,, Sheilds went to Europe to find the bugs' natural predators.  He then searched North America for an equivalent pest.

He was able to find 2 species of nematodes that will go after the alfalfa snout beetle larve.

Sheilds developed ways to grow the nematodes and also developed methods to apply them.

Methods of growing them and applying them have evolved.  To get the nematodes in the sprayer, we used to have to rinse the nematodes out of bait cups through a screen, separating sawdust and worm casings from the nematodes.  Now , nematodes are delivered in a liquid jug, that can be dumped into the sprayer.

The early days,  home made applicators used UTVs and a PVC dribble pipe.  Today, my custom applicator applies with a side dress tubes, every other drop.

Several Land Grant colleges across the US were looking into it,, I don't have the article on which colleges.

I have heard from "someone"(CRS syndrome), that a large dairy in SW Texas or further west ,has had success using nematodes to fight rootworms. 

Currently Sheilds' research has moved on to other pests.  He used to raise nematodes in his lab, but now private individuals are raising the nematodes that we can order.

here is one link to an article about rootworm control

https://blogs.cornell.edu/whatscroppingup/2019/03/22/biological-control-of-corn-rootworm-with-persistent-entomopathogenic-nematodes-an-opportunity-to-try-them-on-your-farm/

Bill

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