Purpletop
Encyclopedia
Tridens flavus is a large, robust perennial bunchgrass native to North America. The seeds are purple, giving the grass its common name. The seeds are also oily, leading to its other common name, "greasegrass". It reproduces by seed and tillers. The grass is often confused with Johnson grass
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Johnson grass
Sorghum halepense, commonly called Johnsongrass, 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 archipelagos...
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