I replied about your black branches on your thread "New sprouts on cutt down ELM tree"

See if the black rubs off with your thumb or a rag, if so it is probably sooty mold growing on aphid honeydew.

No need to prune this tree.

Pre-winter procedure is to make sure the tree has adequate water going into winter. Not drowning, but don't let a week go by without 1 inch of rain - make up any shortfall with a hose set on drip for several hours.

I see you said to use dish soap. How would you apply this? Wouldn't it damage the roots?

Obviously it went through some transplant shock at the begining and lost a lot of leave on top. Now it seems that quite a few branches are going black. I will try the dish soap trick. But again pointer on how to apply it would be good.

Also, this aphid honeydew, would it kill the tree?
and to the branches that are already black, do or should i have to prune them back?

Read the link about aphids, and check to see if the black can be wiped off - if so, there would be no use in removing these branches. People apply dish soap mixed with water in a spray bottle. A forceful jet of plain water from your hose can also sometimes remove the stuff, depending on how sticky it is. Also depends on how much surface area you're talking about - but I'd try wiping it off with my fingers or a cloth if this is practical, before using anything else.

I have no experience with weeping willow, so I don't have a clue if the older branches turn black. I take it that the leaves are not black, just the stems, right? Once again, if this is normal behavior for the tree as the branches mature, there would be little point in removing these branches.

Missed your question: Aphid honeydew will not kill the tree. Aphids are not especially awful as pests go, but they do not help the tree and the honeydew is unsightly.

From the hort.uconn page about golden WW, Salix sachalinensis

Liabilities:
numerous insect and disease problems: cankers, aphids, powdery mildew, rusts, leaf beetles, etc.

Aphids is just a a guess, based on the ants mentioned in your other post. Could be something else, but this is worth looking into first.

Here is a link that might be useful: GWW at uconn hort school

Or . . . .

Willows branches can turn black if they die naturally. For instance, on established trees, branches inside the canopy that don't get enough sun. The tree shuts them down, and they turn black. The black does not rub off, the branch is crispy and dead, without leaves. As long as the whole tree is not black branched, there should be no problem.

Willows in general are difficult to transplant if the don't come from a pot, i.e. digging them up yourself. Often the tree will almost immediately begin the black branch phenomenon, and these branches will be dead too.

Whether it is option #1 Aphids, or #2 here, the problem shouldn't be fatal.

This is exactly right. I also have a new 12' Golden Weeping Willow (planted in April) and throughout the year a branch here or there will turn black and die. It isn't a mildew problem.

Throughout the summer I have pruned back the black ones just to make it look not so ugly. This has caused no problems at all. Right now that the weather is cooler and there is more moisture it hasn't been blackening up at all.

On a side note, I call this tree my rain gauge. If it starts to dry out, I know all my new trees need water. It is very clear about when it needs water and perks back up immediately when watered. If you have the room (which is the key), and don't plant it near your house, it is a great tree. Mine is about 300 feet or more from the house out in an acre of grove planted trees.

Thanks. I will probably prune back some of those dead branches.

In any case, i will take a few of these branches to Sheridan nurseries (where i purchased it) and see what they have to say.
I'm sure it's something natural that the tree's going through. Aside from a few branches here and there, mostly on top. The tree seems to be doing fine.

Once I get an answer, I will let you all know.

Hi everyone,
It now almost November and it's pretty chilly at night 10 degrees or so.
I prunned back all dead branches, but it seems where it had prunned, the "blackness" keeps creeping upward on the same branch pruned........what does that mean?

Should I go ahead and prune the remaining black branches?...Or left them fall on their own?

Also, (ZONE 4, Toronto) is this a good time to prune back the willow?

The leaves are turning yellow and falling off, just wondering if this is common in the Fall/Winter?

Thanks......and help

Willows are prone to canker diseases, start by searching "willow canker". Have never seen any indication of them being hard to move, that's a new one for me.

I love this variety of Willow.. and we lost one last year. It started as black branches, nothing you could wipe off.. and then it spread to the trunk, eventually killing the tree. We still are not sure what it was, canker? Our local nursery guy said to get rid of it asap and burn it because it was highly catchy and would kill my other Willows. He was unable to determine what it was. Any ideas on what this could have been? I love Goldens and want to plant more, but want to control for losing another tree.

How do you control this issue of black branches if your tree is already established and quite large probably 18 foot, way too tall to spray it’s been in the ground for 7 years at least, a golden Willow?