3-4 years ago I bought and planted several Ash and Maple trees. I was told it would be a good idea to put a 2 foot tall 4 inch in diameter vertical pvc pipe next to the tree root bulb when planted, this would allow me put water down to the base of the bulb. The trees did fine and now I am wanting to know how long these tubes should stay or should I take them out, and is there a good time of the year to take them out? Any advice is appreciated! chris in mo.