We have used conduit, 20 feet for 6 years now, good and not too big in wind. Guy ropes are a key ingredient. I would hoist section by section against a tree trunk for stabilization. I see no reason the 10 feet more could not be added all working from the ground more or less. Conduit sizes are 1-1/4 and 1″, could add 1-1/2 at the bottom, all attach with screwed couplings (3 sections per 12′).
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