Chufa (Cyperus esculentus)
This very common plant has a triangular stem and grass-like leaves that are very tough and fibrous. It grows to a height of 20 to 60 centimeters (8 to 24 inches). The mature plant has a soft, distinctive fur-like bloom, with a cluster of flat oval seeds, that extends from a whorl of leaves and four hanging, leaf-like bracts. Tubers 1 to 2.5 centimeters (1/2 to 1 inch) in diameter grow at the ends of the roots.
Edible Parts: The tubers are edible raw, boiled, or baked and have a slightly sweet, nutty flavor. They are quite hard and are typically soaked in water before eating. You can also grind them and use them as a coffee substitute.
Other Uses: The boiled nuts may be used as bait. Soak the nuts in water for 24 hours and then boil for 20 minutes or until fully expanded. Leave them to ferment for 1-2 days.