Johnson Grass
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
(unranked):	Commelinids
Order:	Poales
Family:	Poaceae
Genus:	Sorghum
Species:	S. halepense
Binomial name
Sorghum halepense Pers.

Johnson grass (Sorghum halepense) is a plant in the grass family, Poaceae, native to the Mediterranean region, but growing throughout Europe and the Middle East. The plant has been introduced to all continents except Antarctica and most larger islands and archipelago. It reproduces by rhizomes and seeds.

Johnson grass has been used for forage and to stop erosion, but it is often considered a weed for the following reasons:

1. Foliage that becomes wilted from frost or hot dry weather can contain sufficient amounts of prussic acid to kill cattle and horses if it is eaten in quantity.
2. The foliage can cause 'bloat' in such herbivores from the accumulation of excessive nitrates; otherwise, it is edible.
3. It grows and spreads so quickly that it can 'choke out' other cash crops that have been planted by farmers.

This species occurs in crop fields, pastures, abandoned fields, rights-of-way, forest edges, and along streambanks. It thrives in open, disturbed, rich, bottom ground, particularly in cultivated fields. In Argentina the plant is causing new problems as it is growing resistant to the popular herbicide glyphosate^[1].

[edit] References

1. ^ http://money.cnn.com/news/newsfeeds/articles/djf500/200709261554DOWJONESDJONLINE000700_FORTUNE5.htm

[edit] External links

• Johnson grass - US Department of Agriculture
• Kansas Wildflowers and Grasses - Johnson grass page. Includes photos.
• University of Missouri Extension - Johnson grass