Well-cured hay from healthy mature plants is usually safe. Symptoms of cyanide poisoning include a bluish coloration of mucous membranes, rapid deep breathing, muscular twitching, staggering, weak and irregular pulse, and death. Sudden death without exhibiting symptoms is common. Under certain conditions, plants may accumulate toxic levels of nitrates . Perennial with vigorous rhizomes .
Plants can rapidly develop colonies.
Johnsongrass is considered one of the 10 most noxious weeds in the world. It is especially troublesome in cotton fields in California. Introduced as a forage crop from the Mediterranean region. Summer annual that resembles grain sorghum and corn. It is a major problem in corn, sorghum, and soybean fields in the Central U.S., but is usually less troublesome than johnsongrass in California.