Tridens flavus is a tall, warm season bunchgrass. While the leaves might not grow longer than 2 1/2', the culms can easily grow to a height of 6' or more, and when planted in mass its purple spikelets will create a floating purplish haze.

Purpletop tridens is easy to grow. It prefers full sun, but is not particular about soil. It is adapted to moist to dry, well-drained soils that can be shallow, rocky, sandy, or sterile. It is also salt tolerant, which makes it a common sight along roadsides that are heavily treated during winter. The blooming period begins in mid-summer and lasts 1 to 2 weeks, with the ensuing spikelets persisting through late fall.

This is a very attractive tall grass. It is also attractive to browsing mammals, however, its ability to self-seed makes it easy to establish permanent colonies. [izelplants.com]