Commentary
The word: شَجَر (shajar) in An-Nahl 16:10 ⧉: مِنْهُ شَجَرٌ فِيهِ تُسِيمُونَ (from which [ you grow ] plants, on which you pasture cattle) is mostly applied to a tree which stands on a trunk. Sometimes, it is also applied, in an absolute sense, to everything which grows on land. Included therein are grass on stems or tendrils. This is the sense meant in this verse An-Nahl 16:10 ⧉, because the pasturing of cattle has been mentioned immediately after which is mostly related to grass.
The last word: (tusimun) is a derivation from isamah which means to leave cattle to graze freely in a pasture.