杜父魚[tofugyo] sculpin (any fish of family Cottidae, inc. the bullheads and the miller's-thumb)
杜撰[zusan] careless
杜漏[zurou] careless
杜宇[hototogisu] lesser cuckoo (Cuculus poliocephalus)
杜夫魚[kakubutsu] fourspine sculpin (species of fish, Cottus kazika)

杜絶[tozetsu] stoppage
鎮守の杜[chinjunomori] grove of the village shrine
杜氏[touji] chief brewer at a sake brewery (after name of sake's alleged inventor)
杜若[kakitsubata] rabbitear iris (Iris laevigata)

海棠[kaidou] flowering crab apple (Malus halliana)
秋海棠[shuukaidou] hardy begonia (Begonia grandis)

花海棠[hanakaidou] Hall's crab apple
棠梨[zumi] Toringo crabapple (Malus sieboldii)

杪欏[hego] Cyathea spinulosa (species of tree fern)