You get some light with trees all around, but not many amps out of the panel compared with being out in the open. A 100w panel does 6.3ish amps in full sun aimed right. You might get 1 amp in the trees. Only you can say if that 1 amp is "worth it"
When we will be camping in the trees, I don't even bother taking the solar along (360w all portable)
One good thing for in the trees in the summer, at least it is warm out so your daily AH use isn't too bad. No furnace and lights on all day like in winter.
"Shading" is quite variable too. Shading from something close to the cells is different (worse) from being shaded by tall hardwoods with dappled light coming through the leaves. If you are among cedars and firs forget solar.