POACEAE

Heteropogon contortus

Spear Grass

Grasses & Sedges

Local Context

Common grass of average grazing value, often found on road verges in Raptor's View.

Identification

Growth: Tufted perennial grass (usually 30–100 cm tall), sometimes growing from underground rhizomes, with upright stems and flattened bases.
Flowers: Arranged in a single spike-like raceme (3–10 cm long); the upper flowers feature distinct, long, dark brown to blackish awns (5–8 cm long) that are velvety and characteristically twist together into a tangled knot or spire as they mature.
Leaves: Narrow, flat or usually folded (3–30 cm long and 2–8 mm wide) with a rounded, often hood-shaped tip; they frequently have a blue-green (glaucous) appearance.
Texture: The long twisted awns are hairy; the base of the seed-bearing flowers (callus) is ferociously sharp and densely covered in stiff reddish-brown hairs.
Fruit: The seed unit (spikelet) falls off entirely when ripe (5.5–10 mm long), using its highly pungent, bearded base and long, twisted awn to attach to passing animals or clothing.

Did You Know?

The hygroscopic seeds of Spear Grass are famous for their ability to "dance" and move on their own. Each seed has a long, hair-like tail that reacts to moisture like a tiny spring. When it gets wet, the tail uncoils, and when it dries, it twists back up. This constant twisting and turning creates a drilling motion that physically pushes the sharp seed into the ground, allowing the plant to literally plant itself without any help.

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