Q.I’ve Just Planted My Japanese Maple. Can I Prune It?
I planted this weekend an Acer Palmatum Atropurpureum. It was imported from the mainland, which have a diferent climate. I live in an european island with very cloudy, and rainy winters. I can see that my maple needs some pruning due to several crossing branches. There is also a big branch comming out of the base that should have been cut off a long time ago. Since I’ve just planted the tree a few days ago, should I prune it now? Regarding that big branch comming from the base (shown on first picture), can I cut it right above the branch collar, or by doing it, I’m compromising the good health of the tree? And if I do so, should I use a sealant to give extra protection against all the humidity? What about the lichens (third picture) appearing, should I leave where they are or remove them? Thanks for your help.

Certified GKH Gardening Expert
You can do some pruning now to get your tree off to a good start. I would definitely remove the branch coming out of the base; be sure to preserve the branch collar. What is that coming out of the ground right where soil meets grass? Is that part of your tree? If so, cut that to the ground.
The lichens don't hurt anything. You can leave those.
They don't recommend sealing pruning cuts anymore. It prevents the tree from forming a natural callus.
https://www.gardeningknowhow.com/ornamental/trees/japanese-maple/japanese-maple-care-pruning.htm
https://www.gardeningknowhow.com/ornamental/trees/japanese-maple/japanese-maple-care.htm