I have had a Jack pine for two years now I repotted it and removed one branch shortly after I purchased it. I have been avoiding working on it because I am not sure how to treat it. It has a tight tangled mass of branches and foliage. I don’t want to try wiring it out and ruin its character. How do you manage this chaotic growth habit
Treat it as a Short Needle Single-flush
I know nothing about them 
Very tight ramification? Nursery stock varietal? l hate to put it this way but you asked…but bonsai is partly creating beauty from chaos. Do structural wiring of trunk and primary branches first, then wire secondary and tertiary branches. Create foliage pads to reflect characteristics of trunk (thick trunk - wider pad, thin trunk - narrower pad.). Prune to form alternating branch placement. ln the process, you can impart what you consider to be the characteristic shape of “jack pine” to create a beautiful bonsai. ln the wild, their foliage is not dense but has a light feel about it. Look up Canadian painter, Tom Thomson’s masterpiece “The Jack Pine”.
Thanks David I guess I will have to force myself to try to do something with it this year.
I looks like there are quite a few spots with 3 branches (structural defects) so cleaning up some of those to leave the shorter, better ramified bits might help you see the future of the tree before you dive in full bore.
