草臥れる[kutabireru] to get tired
遺草[isou] posthumous works
一年草[ichinensou] annual (plant)
詠草[eisou] draft poem
下草[shitakusa] undergrowth

仮名草紙[kanazoushi] story in the kana
伽草子[togizoushi] fairy-tale book
海草[kaisou] marine plant
乾草[kansou] hay
甘草[kanzou] liquorice

藻掻く[mogaku] to struggle
海藻[kaisou] seaweed
褐藻[kassou] brown algae
珪藻[keisou] diatom
珪藻土[keisoudo] diatomaceous soil

紅藻[kousou] red algae
才藻[saisou] poetic talent
稚海藻[wakame] wakame (species of edible brown seaweed, Undaria pinnatifida)
藻草[mogusa] water-plants