Dekus have leaves where we have hair,so they are probably photosynthetic.
Dekus have red glowing eyes ,no Arms and their mouths are short, wide, hollow tubes that they can't shut tight. Because of this, they can't swim without drowning but they can "water-hop" (hop across the surface of the water). Dekus have bark rather than skin.Dekus with fairy magic can shoot bubbles of an unspesified liqud(most likely "magic" itself) out of there mouths.Non-magic Scrubs can shoot deku nuts.Deku Scrubs can and do live inside "Deku Flowers".
There are 3 main kinds of Scrubs:
Deku Scrub Biology
These are the most common.
These have red leafs and don't talk.
These have Arms
See also : Goron,Zora,Rito