I have a beautiful 30' blue spruce in my front yard which is beginning to overwhelm the yard. For this reason and to improve curb appeal and neighborhood watch security I would like to prune to raise the skirt from the current one foot ground clearance to seven feet. Are there any precautions or procedures that I should be aware of that are unique to blue spruces? I live in the Denver Colorado suburbs. We just had our first hard freeze so I am think now is a good time to avoid any possible infestations and allow some healing over before insects beome active in the spring.