We always cut them short enough so when they do fail they won't hit a high value target. And yeah, we don't snag cottonwood, willow, etc.
Don't know the history there, but I know Clearance likes his spikes, hates hippies and he liked my snag, so he can't be totally evil.
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Trimmin' bush and caring for flowers is good 'n' all...
but sometimes ya gotta let the big wood fly and pound the garden.