Cyperaceae: Sedge Family
This family contains 4,000 species in 70 genera. They're most abundant in the temperate and colder regions of the globe. The largest genus is Carex which which has flowers that are unisexual on two parts of the inflorescence. Papyrus is made from a sedge, in particular, Cyperus papyrus which grows in Egypt along rivers.
Systematics: Just remember that sedges have edges. While this isn't always the case, it is usually a good way to differentiate grasses from sedges. Sedges usually have solid 3-angled stems with leaves alternate and also in 3 angles. Usually the perianth is lacking and when present is composed of simple scales and bristles. There are typically 3 stamen and branched styles.
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