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If the branch/trunk had to be removed in the first place, it was done reasonably well. There's nothing you can do at this point, except maybe apply liquid copper fungicide (see thread linked below). Willows are relatively short-lived trees anyway, so I wouldn't consider the wound to necessarily be determinative in the life expectancy of your tree. Ideally, the cut shouldn't have been made unless the branch just had to go, but what's done is done.

Here is a link that might be useful: Liquid Copper Fungicide Thread

Yup^. It's not bad really. As Brandon said, if the cut had to be, then this was a reasonably good job of it.

BTW, trees don't heal. Wounds on animals heal. In time, new cells completely replace the damaged or destroyed ones. On trees, the wound remains forever, or for the full length of that plants life. It is gradually walled off in all dimensions by chemical and physical barriers, and by the deposition of new wood as the tree grows. This is known as "compartmentalization". The walling off of wounds is least efficient in the vertical dimension. That's why there are hollow trees.

+oM

i agree.. that is the best cut that could be made ... on any variable i can contemplate ... it is enough of an angle to shed water ... it is not horizontal as you suggest ...

but as an aside ... IMHO.. willow is not a great tree for a small yard.. does it.. in any way overhang anything precious to you ... in the last pic.. is see a house very close by ...

you might want to start mulling its future removal ... and again.. it would have nothing to do with this cut ...

chill on the neighbor.. they did a good job.. IMHO ...

ken

That's not unreasonable -- maybe a bit lazy. I'm lazy like that cutting branches off my small (30') WW knowing it'll heal quickly. At least the adjacent branches don't look like they were cut-into.

Cracks are inevitable as the wood dries & shrinks.

Thank you for your responses.
They are most informative and helpful.