Tim,
In the Rockies, I try to leave a minimum of 3-5 larger diameter snags per acre for cavity nesters and others. Often, I’ll have to leave a few more anticipating that once I open a stand up I am going to lose a few to windthrow. They really need to be a minimum of 10-12″ diameter to make a decent snag. Bigger is better.
I have found that girdling trees to create snages is a mixed bag. Out here the wind blows so hard that often those girdled trees will snap off at the kerf. My preferred method to create a snag is to make a decent slash pile at its base and then torch it…
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