I have been using 3/4" Sch 40 PVC pipe to stake my tree tubes. They have just enough flex that the trunks of the saplings move sufficiently in our relentless Kansas winds to build up some strength.

I used to get 10' sticks for $2.19 in bulk and cut them to 5'. The current price is now exactly double!

I just pull them up and re-use them when it is time to pull the tree tube (or the d*mn gophers kill the tree).

Have you guys had better success with another option?

(I also think they would hold a Treegator well, but I have not yet used any of those saturation bags.)