morphing into a doodad tree

i gave a unit an ability to morph into a doodad tree. this is to make AMBUSH ATTACKS MORE FUN. however, the team color in the is still showing in the minimap. although i set its unit priority to 0. that is to stop enemy units to auto attack it. i still want it to be unseen in the minimap. is it possible to make it seen in a minimap as a doodad tree?

tnx

only way i could think of is to give the doodad tree unit to a neutral player while in tree form.