出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2011/03/24 23:23 UTC 版)
Sword grass is a name used for some species of grasses with blades that are sharp enough to cut human skin. This is because they contain many silica phytoliths, a hardening material in many plants. The sharp blades help to discourage herbivores from grazing, protecting the grasses around it as well.