By Bob Phillips,

The milk jug defense is not a new formation of football players designed to crush opposing quarterbacks. It has nothing to do with the NFL or any sport or game. This is a war maneuver whose purpose is to give the woodland owner a means of protecting young trees from the ravages of Aplodontia rufa, also known as "Boomers".

This strategy was borne of frustration in trying to reforest boomer habitat. You know what I am talking about. After you have spent several years tubing, trapping, controlling brush, and otherwise trying to get your young trees to the free-to-grow stage, and when they are almost there, you turn your back for a few weeks, and the next time you look, your stand of vigorous six and seven foot Douglas fir sapling field looks like a field of broom handles.

What is the milk jug defense? Well, it is a one gallon plastic milk jug modified to clamp around the main stem of your conifers two to four feet above the ground. It fits between the whorls.

The ordinary milk jug is modified by first cutting a two inch hole in the center of the milk jug bottom. Then you cut the jug on the side opposite the handle from the opening in the neck to the newly made hole in the bottom. Next, the milk jug is placed on the tree by opening the jug slightly like a clamshell and placing it around the tree so that both holes fit around the stem. And there it sits as a baffle to stop boomers from climbing the tree and lopping off the terminal and laterals.

Will it work? I don't know, but I'll try anything when I'm desperate. I have placed about 100 on small Douglas fir trees in boomer habitat. They have only been in place for a couple months. So far, they seem to be working. Of course, this is not the season when one expects an all-out attack of boomers. The proof will come in late winter and early spring before other food plants become plentiful. Then I will know whether the milk jug defense really baffles boomers or whether it is just another great idea that didn't work.

Epilogue: Yes, it did work quite well. While it may be a bit labor intensive, losing trees and having to replant is much worse. Remember, not every tree needs to be protected. Boomers usually forage no more than 30 feet from their underground nesting place. Aplodontia rufa is also known as mountain beaver, but are different animals than the familiar beaver that gnaw down trees and build dams in streams.

Master Woodland Manger Bob Phillips is a Clackamas County Tree Farmer.

From the Forest-Tree Leader, a newsletter published by the Clackamas County Farm Forestry Association