I purchased a 50# bag of powdered selenium YEARS ago when we had llamas. I still have a lot of it left. Is there any use for it with cows, gardening, pastures, compost? Or something else?
Deschutes County Oregon small farms
https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9094.pdf Check out this publication using Selenium as a "fertilizer" (plants do not need Selenium to grow, but animals and people do need). if you use it as a "fertilizer" you will want to be very careful and precise in the rate of actual selenium that you apply. There are different sources of Selenium products. We have just finished up fieldwork at 3 sites across Oregon looking at Selenium rates with and without sulfur. We found that Sulfur did not restrict Selenium uptake by plants. Probably be this winter or next spring till published.
Deschutes county is Selenium -deficient. One could use it on gardens or hay fields or pastures. Again be precise with application rates. I think one could raise and sell Selenium -enriched hay. or Selenium-enriched vegetables or fruit….
Area Extension Agronomist
OSU Extension Service
OSU Crook County Extension Service
Prineville, OR 97754