Hey guys I hate to rain on your parade but you must have sunlight on the ground around the tree. Soil temp helps determine when the tree buds in the spring. You may push the budding time by weeks or more, shorting your growing season. I live in a frost pocket (no direct sunlight in winter) so I know of what I speak.
I have been noticing each spring the areas of our property that warm up super fast and those that keep their snow load the longest..it helps to plan that way also, by good observations during the seasons
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