Do nothing, apply nothing. Sure, it's bad that this happened, but trees have been losing limbs since long before us hairless apes showed up, and are programmed to deal with it. No, there is no magic potion that should be applied to that wound. One occasional member here has in fact developed a "liquid copper fungicide" which from his accounts I believe actually works, but that is for large wounds on valuable timber trees, not this little pear ornamental tree. No need to do anything.

properly prune it off at the trunk ... do you know how??

remove all hanging weight.. before you make the last cut ...

apply nothing.. its against nature ...

ken

@wis & ken, thank you for the responses. I've read elsewhere that cutting the limb may be best for the tree, but, "do nothing," also resonates. Which leaves me a bit torn, no pun intended. Any other thoughts?

Other thoughts?

Is that a maple of some kind?

Maybe post a pic of the whole tree.

From the bit I can see the limb looks low on the tree and a bit large for the trunk. It might have been up for pruning consideration anyway.

Ditto what Toronado (and Ken) said. If it were me, I'm pretty sure I'd remove the branch. There's a small chance I'd change my mind if I saw it in person, but looking at the pictures leads me to believe that pruning would be my choice.

BTW, the third options (and maybe the best one), is to leave it for now, see what happens, and make the final decision in a year from now...or two years from now. You could even do some minor pruning in the mean time to lesson the percentage of the canopy that that limb was responsible for. Doing that, in a happy coincidence, would likely increase the trees ability to close off the pruning wound more quickly, later on (kind of a subordinate pruning type of thing).

Remove it now. You are lucky the season is right and it didn't pull bark off trunk. The water and nurshment that would have gone into it will redirect to remainder of tree increasing overall growth. It should have been gone long before now anyhow unless the picture is realy decieving. In the fall,stand back and consider if one or more other limbs should be removed next winter to balance tree.

It's obviously a short little pear or some such, not a shade tree. Therefor, no recommendations from my corner to do much of anything, except leave it well enough alone. In ten years-which is nothing in tree terms-that tree won't even be there anymore. Why make a big deal out of essentially nothing?