Redbud. It’s got such pretty blossoms and the leaves are a really pleasing shape.

Plus birch beer is awesome

But why use such an awkward construction? Why not “please handle this” or “please take care of this”? Or even “please take the necessary steps to address this”? “Please do the needful” is saying Please [VERB] the [ADJECTIVE]. But the correct construction is to verb a noun. So you need a noun (e.g., “this”) to act on.

And additionally, “needful” is an adjective, and rarely ever used anyway. For example, you could probably describe a homeless person as “needful”, but it sounds awkward, and most people would say “needy” or “in need.”