Purple Nut Sedge is an Invasive Plant
Les Harrison is the Wakulla County Extension Director
Autumn is the season to harvest nuts for both the human and wild residents of Wakulla County. Hickories and oaks are producing a bumper nut crop for the squirrels, deer and other wildlife which are dependent on the fat and nutrients to make it past the cold season.
Pecans and peanuts are both available fresh for the picking or purchasing, as are chestnuts for those who can handle the burrs containing the nuts. However, there is one exotic nut not on any list of popular fall delicacies.
Purple nut sedge, Cyperus rotundus, grows from every possible sunny location with soil. This non-native plant is a rapidly spreading perennial which will take every opportunity to colonize new locations.
The identifier purple is in its name because there is a purple-tinged section of this sedge where it emerges from the ground. The plant is sometimes referred to as purple nut grass because of its long narrow leaves and its erect growth pattern originating from a nutlike basal bulb.
There are other sedges in Wakulla County, but only yellow nut sedge is identified by a specific color. It is sometimes called chufa and is a popular feed for wild turkeys, and turkey hunters.
The dark green, smooth leaves blend in easily with many turf grasses during the spring and summer. Beneath the soil’s surface and out of sight, the root system grows in every direction.
Purple nut sedge’s roots are a series of spreading rhizomes and tubers or bulbs identified as nutlets. Each nutlet sprouts a new bunch of grass-like leaves and continues growing the rhizomes.
The dense population of this sedge quickly crowds out most other plants, but especially turf and forage grasses. It can reach a height of 18 inches on its triangle shaped stem.
The root system’s design assures this plants continued success. If pulled, the rhizomes break off leaving a large number of nutlets to develop and emerge at a later date.
If plowed or tilled, the nutlets are detached and spread to new and inviting locations. Many times nutlets lodge in tillage equipment only to shake loose and deposited in un-colonized locations.
Most herbicides have little effect on this sedge’s hardy root system. Selected pre-emergent herbicides will prevent many of the nutlets from germinating in spring if properly applies.