I have about 2 acres of johnsongrass in my hay meadow that is mostly bermudagrass. Would I be safe to bale the hay and feed it to horses?

Cyanide concentration drops to safe levels in johnsongrass when cured for hay, and it is safe to feed.
The leaves and stems of johnsongrass contain a cyanide compound, which when metabolized, inhibits the body’s ability to absorb oxygen, in effect suffocating the animal; young shoots of johnsongrass contain the highest concentration of the toxin. Because horses do not metabolize the cyanide compound as efficiently as ruminant animals do, grazing healthy adult plants is unlikely to harm them, but circumstances that …