Cyperus rigidellus facts for kids

Cyperus rigidellus is a special type of grass-like plant called a sedge. It belongs to the Cyperaceae family, which is a group of plants similar to grasses. This sedge is native to Australia, meaning it naturally grows there.

About Cyperus rigidellus

This plant can be a short-lived perennial (meaning it lives for a few years) or an annual (meaning it lives for one year). It usually grows to be about 5 to 40 centimeters (2 to 16 inches) tall.

What it Looks Like

Cyperus rigidellus has stems called culms that are three-sided with sharp edges. These stems are often rough near the top. They are typically 3 to 25 centimeters long and about 0.6 to 1.3 millimeters wide.

The leaves of this sedge are usually longer than its stems. They often have a curly tip and are about 3 millimeters wide.

Flowers and Seeds

The plant blooms between April and November, producing brown-red flowers. Its flower clusters, called inflorescences, can be simple or have one to four branches. These branches are usually 1 to 6 centimeters long.

Each flower cluster is shaped like a ball, about 30 millimeters across. It can be loosely or tightly packed with flowers. The flattened spikelets (small flower clusters) grow in groups of 5 to 15. Each spikelet contains 6 to 25 tiny flowers. These spikelets are 4 to 25 millimeters long and 2.5 to 4 millimeters wide.

After the plant flowers, it forms pale brown nuts. These nuts are three-sided and have a narrow, oval-like shape.

Its Discovery

For a while, Cyperus rigidellus was sometimes mistaken for other sedges, like Cyperus gilesii and Cyperus enervis.

The plant was officially described for the first time in 1929. This was done by a botanist named John McConnell Black. He included its description in his work called Additions and Corrections, which was published in Flora of South Australia.

Cyperus rigidellus has several other names it has been known by over time. Some of these include Mariscus rigidellus and Cyperus subpinnatus.

Where it Grows

You can find Cyperus rigidellus in all the mainland states and territories of Australia.

Specific Locations

• In Western Australia, it grows near streams and creeks. It is also found around clay pans, on flood plains, and in other damp areas. These places are in regions like the Mid West, Pilbara, Gascoyne, and Goldfields-Esperance. It prefers to grow in loamy-sand or clay-sand soils.
• In New South Wales, this sedge is found in inland areas. It usually grows in places that are wet only for a short time, such as floodways and roadside drains.