Johnson grass is native to most of Asia and North Africa. It was introduced into North America in the 1800s as cattle forage and is also naturalized in South America and much of Africa and Europe. It is generally considered an invasive agricultural pest. It grows aggressively in dry, open habitats like grasslands and pastures.

Human poisoning from johnson grass may occur if mistaken for edible sorghum. Cats and dogs risk poisoning from ingesting johnson grass leaves, exhibiting symptoms of discomfort and illness. It is critical to keep johnson grass out of pets' reach and seek immediate veterinary care if poisoning is suspected. The risk increases under stress conditions like drought or frost.

Johnson grass is thought to be native to the Mediterranean region, though the exact range is disputed. It is now present throughout Africa, Asia, Europe, the Americas, and Oceania. It is considered a serious weed in at least 53 countries. In the United States, it is listed as invasive in over half the states and is reported as an agricultural weed in most states of the southeast. It has been cultivated as fodder or forage crop. However, it is toxic to some animals, presents a fire risk, competes with and can be toxic to other plants, and reduces soil fertility. Its extensive rhizome system and aggressive seed production allow it to establish and spread quickly. It commonly invades agricultural fields and is an alternative host for various crops. An integrative management approach using competitive crop rotation, repeated tillage, and herbicides is recommended to control johnson grass.

For effective removal of johnson grass, fall is the ideal season, preferably before the plant seeds. This not only restricts the spread of johnson grass but also lessens the chance of regrowth in the next season. Here are some methods to assist with the control or removal of this plant: