Mulberry die back over winter

My mulberry trees, especially the alba, have a lot of dieback during the winter.  

On the Left Coast of Canada, we don't get very cold winters, but we do get wet ones.  Even if the nights get below freezing it usually warms up during the day.  That said, we can get a couple of weeks where the daytime high is below freezing.  We always get a bit of dieback on the Alba, maybe 10-20%.  It just doesn't like our winters.  But I trim off the dead branches in the spring and they grow like mad come summer.  

I've tried coppicing and pollarding them like they say we should, and that just increases the dieback.  What works best on a normal year is to prune for shape in the fall and then prune the rest of the way as the leaf buds start to break.  

Over the last 12 months, we've broken weather records for heat, drought, rainfall, and cold ever recorded.  Spring is very very late and the rainy season is almost a month longer than normal.  So it's been a rough year to be a tree.  But the mulberries took it all in stride... until now.

They are starting to leaf out and it looks like most of my Alba have died back to the main stem and a couple to the ground.  The other mulberry varieties aren't suffering so bad from dying back but the leaves are a bit yellow compared to normal.  

...

What can I do to lessen dieback?

What general care can I give them to make them stronger?

They seem to love having the chickens run next to them, but given the already acidic nature of the soil here do I need to be giving these trees lime from time to time?  

I noticed several of my mulberries died back to the main trunk.  They were all World's Best Mulberry and one Pakistan Mulberry never did come back but it was a recently grafted seedling.  My others (all wild) and a couple I got from England's nursery did very well.  We too, had a mild but wet winter.  

All 21 of my mulberries look very unhappy this spring. Either they have yet to leaf out, or what leafed out early died back in frost and hail. This is in contrast with most other species, (i.e. all 28 cherries look good). We have some difficult rocky serpentine clay soil, but I was told by a neighbor cherries seem to like it here, and alas they do. I would not have thought mulberries would be the thing to struggle given their supposed wide-ranging soil tolerances, but they’ve done the worst among the 600+ trees of dozens of species that I’ve planted so far here.

My Pakistan and another less cold hardy mulberry have died back previously.

Pruning them seems to increase their cold susceptibility. Since I stopped pruning them they barely have any dieback now.

I've got 2 mulberries, both in half-barrel tubs because there permanent homes haven't been determined yet. The one that is to the west of our metal well shed did much better this year than the one that had no shelter from any winds, but I don't know if that's a factor or just chance. It may be a factor because we not only had a much wetter than average winter/spring, we also had some bouts of unseasonably cold overnight lows.  I lost a Hazelnut that was planted on a hugel that must have been there close to 10 years and was if anything, the healthier of the two hazels in that area - but it was further from shelter than the other also.

My mulberries are supposedly "Morus alba" and the one that did better is a clone of the one that didn't do so well.

Steve Thorn wrote:My Pakistan and another less cold hardy mulberry have died back previously.

Pruning them seems to increase their cold susceptibility. Since I stopped pruning them they barely have any dieback now.

I wonder if this might be the ticket.

I'm not sure what variety is outside the goat barn where I live - it was here when my landlady bought the property 10-12 years ago. This 40-foot tree has not been pruned except for a huge chunk that split off and fell on the barn roof before I moved in, and then a large split branch that fell off the year I moved here (2020). There is even a second split branch that really needs to be removed (for 2 years now), but hasn't been touched.

It's loaded with berries. Haven't noticed any die off (besides the splits).

I'm outside of Carnation, though higher up in the forested hills surrounding the valley, not the valley floor or in town. We are 30+ miles east of Seattle, and just 40-some miles from the nearest pass over the Cascade mountains, so we are typically colder, and wetter than Seattle is. So not too dissimilar to your climate, I would think r.

The attached pic are the mulberries on this giant tree as they looked 3 days ago. Little babies!

I have a Mulberry in my back yard, but I would be hard pressed to give a name too it. Last Fall I pruned it back and this Spring I cut off dead limbs and so far so good-waiting for berries.

I purchased it when my granddaughters were little and loved picking berries from trees wherever we walked. If I was to rewind that decision, I would have researched a native version of the mulberry hoping they were in fact native in Ontario. Slowly, I am discovering we select hybrid trees (for I am sure many good reasons) that don't have the ancestral knowledge to adapt as the local climate goes through its wild shifts. I have non-native plants and yet all of the new ones I select will be native. They are better for the local bees and birds and bugs and they have a fierce determination to be here. One other idea is to find a "volunteer" tree somewhere that's already faced the challenges to building new life, and replant it in your yard.

I adore Mulberries and I hope you find an answer.

We’ve got 2 young (about a foot tall) mulberries and live near the US zone 3/4 border. One is a dwarf weeping mulberry and i think the other was called Trader, maybe Moris Nigra. The dwarf looks pretty good, no dieback and a little new growth. But it has some protection from sun and wind. The Trader is out in the open with nothing but some comfrey nearby for protection. It definitely is struggling, probably for a variety of reasons, but is still alive. We’ve got quite a bit of clay in our soil and our winters get to -30F or below.

Ben Zumeta wrote:All 21 of my mulberries look very unhappy this spring. Either they have yet to leaf out, or what leafed out early died back in frost and hail. This is in contrast with most other species, (i.e. all 28 cherries look good). We have some difficult rocky serpentine clay soil, but I was told by a neighbor cherries seem to like it here, and alas they do. I would not have thought mulberries would be the thing to struggle given their supposed wide-ranging soil tolerances, but they’ve done the worst among the 600+ trees of dozens of species that I’ve planted so far here.

Mine have mostly kept dying back something awful every winter. This year, it is definitively worse. Of 26 trees/ bushes, I'll be elated to have 10 survive.
Since I live in zone 4b, I thought it was because they are at the limit of their range, but this thread tells me different: there seems to be something *this year*, this past winter that is different. I am in zone 4b, in extremely sandy soil, with water at 10 ft. The PH here is around 6.5. Our last winter was mild, with a little less precipitation perhaps, but not that different.

I'm not at all a mulberry expert; I have one old male alba that grows fine with no intervention from me, and a tiny baby nigra that is doing well so far aside from minor battles with chickens. I'm in zone 8a, so it's a different ballgame,  too. However, in my research when looking for what variety I wanted to add to my food forest, I happened to read that mulberry should only be pruned in winter because they have a hard time healing and branches will die back a bit where pruned.  Given the earlier comments about pruning, this seems to fit.  If it were me, I'd either stop pruning for a season, or only prune when the mulberry is 100% dormant.

How to make your mulberries happier? I'd try giving them a grape to hang out with. Supposedly they both grow better when planted together. (Jack Johnson songs playing in my head now).  I just planted a grape vine on my old alba and they both look cozy. So far, so good!

Best of luck!

Oh crap. When I posted above, bragging about how well the huge neglected mulberry has done, I hadn't even glanced at the small mulberry in a chicken paddock adjacent to the goat pasture.

This smaller mulberry, only 8 feet tall or so, is in the center of a chicken paddock, with comfrey growing at its base. It also has not been pruned, but looks like it had some serious die back on almost half of its branches.

Even though it is a small paddock, being in the center of it means the mulberry tree does not have shelter on any side.

The huge, massive mulberry nearest my living space is right up against a thick evergreen wooded area - which protects it from the *north* side. Said evergreen wooded area is full of mature, 80+foot tall evergreens such as cedar (Thuya plicata, not really a true cedar) and fir trees. Also, the building I live in is on the east side of the tree, which, while not directly adjacent, likely offers some protection as well. There is just one small, lower branch on the big mulberry - the most SW of all the branches, which happens to be the farthest out from the protected sides - that does look like minor die off on the end of the branch.

So I'd guess the northern evergreen wooded area protected the mulberry more than anything, and possibly its size/maturity, too; and to a lesser extent the building to the east--and not the lack of pruning.

(Edited to add the building to the east as another potential protection for the large mulberry.)

Thinking about last year.  I did the usual harvesting of branches in the first half of the summer.  But then I did a bit of a trim in Augest.  The tree that got the most trimming is doing the worse.

So maybe the key is not to cut the branches after Augest?  

Cutting back the dead wood yesterday, I noticed that one tree has a lot of orange dots (mould or fungus?) on the dead branches.  But it's not on the other trees.  

Ah. r, you asked about acidity and lime.

The mulberry in the open in a chicken paddock, has had occasional chickens around it in the two years I've been here, but not often. They were mostly kept out do to holes in the fencing here and there and no time to mend them. There has been no other care in that paddock.

The mulberry in the goat pasture has not had goats (or chickens) in the two years that I've been here. *BUT* I have been spreading my wood stove ashes in the pasture and around the tree a bit. Not much. Haven't wanted to over alkalinize.

Plus, I have put old goat manure and kitchen scraps along the NW part of the mulberry tree's drip line. Additionally, for a year and a half, I've mowed under the tree, leaving all clippings to fall where they may to improve the soil and pasture grasses.

So there is another difference with the two trees I suppose. Who knew there were so many differences? Ha.

r ranson wrote:Thinking about last year.  I did the usual harvesting of branches in the first half of the summer.  But then I did a bit of a trim in Augest.  The tree that got the most trimming is doing the worse.

So maybe the key is not to cut the branches after Augest?  

Cutting back the dead wood yesterday, I noticed that one tree has a lot of orange dots (mould or fungus?) on the dead branches.  But it's not on the other trees.  

When I prune trees it is in the winter. The tree is dormancy, diseases and pests are not very active. I think is may be a bacterial issue see link for more information http://ipm.ucanr.edu/PMG/GARDEN/PLANTS/DISEASES/baclfblight.html
If it is a bacterial issue I would clean my pruning equipment then follow up with sanitizing. So the bacterial would not spread to other plants or re-infect the tree.  

I have many seedlings and 5 full sized mulberry trees.
Only the one I actually paid for struggles.
The rest thrive no matter how I abuse them.
This doesn't include the 3-4 trees I half heartedly try to kill, because they are in bad spots.
I can shave these stumps bare repeatedly, but they just won't die.

Rather than rejecting the cultivars maybe the thing to do is landrace them.
Normally I wouldn't suggest that for trees, but mulberry trees are so prolific and precocious it wouldn't take too top long to get some results.

William Bronson wrote:

I can shave these stumps bare repeatedly, but they just won't die.

I have heard about several places in the USA where Mulberries are pretty much considered a pest. Alas, that is not true of the Pacific Northwest, where both I, r ranson, and I think Jocelyn might describe her location as PNW as well.

We had a very wet spring. We also had intermittent cold snaps that were also wet. I was told that Mulberries like damp places, but maybe this is pushing "damp" to the extreme?

When I looked today at the more sheltered of my 2 trees, it had lost a lot of its small branches lower down. It's *very* slow to be showing leaves and I don't think I've seen flowers at all yet. I will try to remember to have a good look at the other tree later.

I have seedlings and saplings of all three species (Red, white and black) mulberries in various locations around my place. These have all been grown from seed by me. I did notice that with the colder than normal April and May we had in Michigan this year, all of them took longer to leaf out than last year, but only had dieback on trees that were browsed by deer or other critters over the winter. I also had deer peeling strips of bark off of my black locust and mulberry saplings for the first time, fortunately they only actually killed a couple.

What surprised me about what OP said, is that they are growing white mulberry, which is the most cold hardy, so I honestly doubt the dieback is due to the very mild winter (compared to here in Michigan). I would look at possible browsing or maybe even some cause for late season growth last fall, as new growth will almost certainly not survive winter. Pruning before dormancy will certainly encourage this new growth, so the comments related to that make perfect sense to me.

I had massive die-back in my 3 year old mulberry silvopasture this year.  I thought I had done something wrong like prune them during the wrong season... but this thread makes it seem like something else is going on.

I too have noticed the little orange "spots" on the bark just above any branch that died back.  It also seems that the bark itself is affected and looks like the vascular tissue dies and sort of caves inwards towards the trunk at each affected branch.

I had some trees make it through winter, leaf out just fine, and THEN succumb to whatever is killing the vascular tissue.  After leafing out and looking great, they wilted and dried up in the sun.

This happened in about 2/3 of my dwarf-everbearing mulberry trees that I cloned and had in the ground, a good 6-8 feet tall this year.  The ones that did survive the winter have fruited for the first time, but the others have essentially died back to the ground.  I have never had this issue in the last few years of growing these trees.

The two 10 year old wild-type mulberries that I grew from collected seedlings appear just fine.

It appears to be something fungal that enters at dead or cut branches, but hard to tell.  I have decided to not prune anything from here on out and just let them do their own thing!

I've had severe dieback every winter and I'm starting to wonder if it is even worth the effort as I am not even getting any fruit.
The few that form are small and detach very easily. Right now, their main attraction is that while the birds are busy with those, they leave my cherries alone.
Mine were grown from seed from wild specimens and are not pruned. Deer may nibble on them, I suppose, but there is no evidence of drastic attack coming from them. Grown as a bush or trimmed to make them as trees, it seems to make no difference: In the spring, when they fail to grow, they still have all the branches they grew last year. I may have to ask an arborist...
I am truly at a loss to figure this one out. Zone 4b, extremely sandy, first water at 10 ft.
Since they come from wild, local specimens, I have not added fertilizer except for the first year. They made exceptional growth that first year. I mulched some with my chickens' manure and watered others with my comfrey tea.
I will have a closer look for lesions or bugs or spots or???