Tree Watering Bags

     We've all seen them on trees: those plastic watering bags.  They go by a variety of trade names and are easy to find and buy on line.  But I have always wondered if they are a good idea.  It seems to me that these bags, while they probably do provide water to the trees, also keep the soil and the tree bark consistently damp.  I don't see how this can be good for the tree, and will only invite fungal rots and other infections, plus insects, to attack the tree and the roots.  In addition, it seems that these tree bags could create a nice cozy home for various small rodents that may girdle the tree and potentially kill it.  I did some online research and could not confirm these suspicions, but recently heard Mike McGrath, the organic garden guru, on his show on NPR "You Bet Your Garden" suggest the same thing.  He said the the best way to water a newly planted tree is to let a hose drip next to it overnight (just a slow drip) and that watering bags can do more harm than good (for the reasons I mentioned).  Instead of an open hose, I like to use a soaker hose that is in a circle shape specifically designed to slowly water new trees and shrubs.  I might turn it on to slowly drip soak for 6 to 8 hours once or twice a week for a few weeks, then weekly thereafter until the tree seems established.
     One more note:  it is best to plant trees in the fall, but most nursery stock is best in spring with greater variety available.  I don't hesitate to plant in spring, as long as I am committed to watering the tree regularly throughout the growing season (hiring a garden helper when I go aay on vacation).  Mike McGrath gives his full tree-planting advice, worth reading, at:  http://www.gardensalive.com/article.asp?ai=1241

(U. Minnesota Extension Service has a photo of a growing bag, which they recommend, even though I do not agree with their advice, at:   http://www.extension.umn.edu/yardandgarden/YGLNews/YGLNewsAugust12007.html  ).  Seems like we need someone to really research this practice!

Happy gardening!   Spring is coming!