Two words: Beware Borers.
I had a seedling that was developing into a nice shohin - it was my "cut to shape" guinea pig. Planted it on a tile. Nice nebari / root flare developing. Fine twiggy-ness, ramification going well with small internodes & tiny buds. And I happen to like young prunus' shiny bark patterns.
Operative concept in previous paragraph: past tense verbs.
Borers got it (last summer). It was on a back bench (the "grow-out" rows); I didn't notice anything wrong 'til it was too late.
Aside: Still don't know what a good borer remedy would be. I'm open to suggestions - something commercially available today to the average person without a pesticide license using moderate personal protection at most - Space suits out, but I do have one of those masks with filter cartridges & rubber gloves. [Please - nobody suggest lindane & other great borer remedies that are no longer available to the average person, if at all.
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Anyway - the seedling came from my woods (it was in the way of a small clearing I needed). I have mature black cherry around; I'm not sure I'll bother with one again until I have a "borer plan". I was told they were "borer magnets", and it unfortunately appears to be true in my neck of the woods....
So - practical advice to you - the tap root can be managable. It might have been better to spend a season or two developing some side-roots before collection, but you've already collected it. I didn't have any trouble with my initially-nothing-but-a-tap-root seedling when I nipped the tap. Granted, seedlings are more vigorous (don't know how old your collected tree is). Assuming your tree survives the initial collection - you can develop a good root system.
Do watch out for pests, and have a plan for "what if..."
Hope that helps, and good luck with your black cherry.