Pruning questions

[Haro]

I have been doing a lot of reading but one question that I cannot find an answer to. I have quite a few maples that I call fence row trees some are fairly normal but about a dozen have a good size stump but split into as many as 10 trees/branches as big as 18" each. They say when the trees are young you should prune any branches that are growing like this, but these are not young trees. I'm not sure if I should cut all but one or just try tapping each branch. I did tap a some of them and got good results from two or three, others were not much at all. also would it be better to do this now?

[Thompson's Tree Farm]

If the stems are already of tapping size. I would put a tap in each one. I'd only "thin" them if one of the stems was very weak. diseased. had a lot of dead wood. or seemed to threaten the health of the rest of the stems.

[Haro]

Ok, even though I have the urge to thin them to one or two I'll just clean them up for next year. I do have one that may have to come down in the near future, so I may try thinning that one and compare the sap volume with another one that is of compareable size over the next couple seasons