also: せいそう
Refers to grass that is green and growing, often in contrast to dry or withered grass. The reading あおくさ is the everyday term; せいそう is a formal or literary variant.
春になると、野原に青草が一面に生える。
In spring, green grass grows all over the field.
牛が青草を食べている。
The cows are eating green grass.
Standard kanji spelling for the common reading あおくさ.
Rare Sino-Japanese reading; mostly encountered in formal or literary contexts.
Compound of 青 (あお, 'blue/green') and 草 (くさ, 'grass'). The reading せいそう is the Sino-Japanese on'yomi reading of the same characters.