Do you know that there is a maple forum and that much of the discussion there is about Japanese maples?

Not sure I'd do anything with it. Those sorts of congested joints/narrow crotch angles are not uncommon with many JM's. And this one is acting almost like a single trunk and in no danger of splitting. If it hasn't posed a problem to this point and would significantly alter the aesthetics of the tree if removed, I'd be inclined to leave it be.

welcome to the forums ...

i cant tell from the first pic.. how far apart the two main branches are ... it seems they are apart .... so i would leave them alone ... for now.. there is no emergency that requires fast action ... imo

but i see a smaller side branch ... that appears to be rubbing on the right trunk.. i would just take that off properly ... do you know about branch colors and what not???

if the main two trunks are not touching.. in tree time.. you have plenty of time.. perhaps a year or 3.. to figure out if you want to take one of those off ... there simply isnt any hurry ...

in the mean time.. and presuming sooner or later.. one has to go .. you would guide smaller branches on the other.. so as to not create a giant hole in the canopy when you remove one or the other ...

if you do decide to take one or the other.. do it in stages ... it would be quite a shock to a tree.. if you remove half the canopy any given year ....

i cant believe the graft would be that high ... but that is a weird junction .. after it leafs out.. make sure both parts.. are the same JM .... it wouldnt be great to cut off the prefer grafted plant ... leaving the more common root plant .. again.. this is just speculation ... im not sure i see it in your pix ....

ken

maybe if you took a pencil or something.. and put it in the gap.. and snapped another pic or two.. it would help us define the issue ...

It doesn't really matter if they are touching or not. Inosculation or the permanent fusing of touching branches is also quite common with JM's and actually creates a stronger structure to the tree than if the branches were just growing very closely.

Long term the two trunks will start to fuse. You may not have long term issues but there is a stronger likelyhood you would vs not having issues. I'm talking 10 to 20 years from now.

Based on the caliper and overall angle I may be inclined to leave it too.

I would at a minimum remove the interfering laterals that are near the area where the to two trunks meet. For example first pic - half way up the right side trunk - remove that branch from the left side trunk.

When to cut? Either early summer or late summer otherwise these these weep sap like crazy.

Like Ken, I am also wondering if the straight trunk is from the root stock and the other one is grafted. In the first photo it kind of looks like the graft might be just below ground level. Hard to say.

That is not the graft union. If that were the case, the appearance of the two major branches would be quite distinct whne they were in leaf. The differences would be obvious. Since it is unusual for a graft location to be very high on the rootstock for anything other than low growing weeping forms, I'd guess the graft to be at ground level where the bark color is slightly different. Skilled JM grafting will result in almost invisible graft unions.

thanks for all the comments.

here are some additional pictures that were requested.

should I cut a spacer to prevent the branches from rubbing where the pen is? at this point I will wait until later in the year to prune any interfering branches.

joel

With more detail on the included bark and angle I would make a subordination cut in early summer and then I’ll cut the whole thing off early summer next year

And from a different viewpoint, I would just leave it be :-) If there is no obvious sign of any rubbing (bark scraped off, etc.), I'd just leave the two main branches to inosculate with time. These unusual growth patterns and branch structures - which would never fly in larger growing ornamental trees - are part of what makes Japanese maples the highly sculptural specimens they are. But then I grow them in a climate where they grow like weeds and not much of anything....other than deer....bothers them.