Guinea Grass, Colonial Grass, Tanganyika Grass

Guineagrass, Colonial Grass or Tanganyika Grass (Panicum maximum or Urochloa maxima) is extrremely invasive and hard to get rid of once e...Read Morestablished. It is VERY, VERY invasive throughout many tropical and subtropical areas, including parts of the southern United States, the Caribbean and Hawaii (zones 8a through 11).

Guineagrass is native to Africa. However, it has been introduced to many warm areas worldwide and is now a serious weed in those areas.

It is very invasive in much of Florida, especially from north-central Florida southward throughout the rest of the state, in both disturbed (including vacant lots) and natural habitats. It is especially invasive in abandoned fields, vacant lots and parts of sugarcane fields. It is also an agressive invader of natural habitats, where it chokes out and greatly displaces native vegetation.

Once in a yard, it can be difficult to eradicate. It is a tough grass, surviving drought and (even though it often dies during periods of dry weather or drought) growing back up when it rains.

Guineagrass in the U.S. has also been reported in Georgia, Alabama, Louisiana, Texas, Arizona and California, and is well-established and invasive in Hawaii.

If you have it, you won't want it. It is a pure weed!

In the United States, Panicum maximum is scattered in the southern states, but is most common in peninsular Florida (and perhaps southern...Read More Texas) - see Flora of North America, Vol. 25, p. 505. In central Florida it is a very common weed of citrus groves, roadsides, and "waste places". Even though there is a lot of it not far away, I have so far not noticed it seeding in to my Sebring, Florida garden (even though I have other Urochloa species as garden weeds!)

Do not plant it. If it shows up in your garden, you will face an alternative meaning for its scientific name (Panicum means millet...Read More, but could very well mean "panic", I tell you!) This is officially the most invasive plant in the tropics and subtropics, quickly covering any sunny area on any kind of soil. If it´s too dry, the plant will dry up and come back periodically along with the rains.

It´s a tall grass that came accidentally from Africa along with the slave commerce, with long and sharp leaves, and the inflorescence can reach up 2m tall. It produces lots of seeds (if the vegetative reproduction through rhizomes wasn´t enough), and will spread everywhere. In no time, your garden will be dominated by this plant. Dig any suspect seedling as fast as you can, not only in your garden, but anywhere, don´t let this beast propagate in your area.