Answer: Your new trees should be watered deeply once each week until their root systems become established. If you water frequently (and shallowly), the roots will remain close to the surface - not a good thing for sequoia trees. Even though you have 20 trees and it will be labor intensive, I'd suggest turning off the drip system for now and building watering wells or basins beneath each of the trees (mound soil up in a 10" circle all around each tree). Then once a week fill the basins, allow them to drain, then fill them a second time. This will concentrate the water over the root masses, allowing it to trickle down and wet the entire root area. Don't feed your trees until next spring and don't spray with anything at this time. Just water deeply once each week and they should recover from their transplant stress.
Best wishes with your new trees!
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