Sedges have solid, triangular stems, and their leaves come off the stem on three sides. Oftentimes, their fruits are clumpy and a bit bristly. Nut "grass" and McCoy "grass" are two common sedges I find in my yard. Water chestnuts and papyrus are also sedges. Remember, it's the stem that has the triangular shape; the leaves may be quite flat. Hawaii has eight endemic species of sedge. The beautiful Cyperus trachysanthos, or ka'a can get as large as a couple of feet, and looks striking when planted in groups. |
Rushes are most often associated with wetlands. They have a round shape, and may have round or flat leaves. They feel spongy when compressed. Juncus effusus is one member of the juncus genus that is present in Hawaii, but is considered invasive, as it displaces natives in forests and bogs. |
Grasses have stems that are hollow. Try clipping a stem and you'll see. Note also that the stems are round or flattened, and there are nodes where the leaves attach and wrap around the stems. The leaves grow out from the stem on two sides, and have parallel veins. Heteropogon contortus, or pili grass, is one species that is familiar here, although it is less prevalent than it once was. Pili means to stick, or adhere, which refers to the way the spike and awn can drill there way into the soil, or whatever brushes by. |