Trees in terrible condition everywhere - advice and opinions needed

[Quercus Robert]

Hi,

 

I live in Portsmouth (UK). Since this Spring, I have begun noticing the condition of the trees in the area. At first, I focused on the horse chestnuts which, as we all know, are suffering greatly (I'd say catastrophically) from the leaf miner beetles. I know a guy who has for a little while been pretty alarmist about them, saying they'll be completely gone from our countryside inside two decades. I didn't agree with him at first but now I would go further; they're in a terrible way, even the trees with zero visible infestation - featuring simply scorched leaves and die-back. Old, young, it makes no difference.

 

The next species that drew my attention is the cherry - principally the blossom trees planted by gardeners and councils but cherries in general. I saw that the ones I passed regularly were showing defoliation (in June), die-back, leaf-scorch, but also horrific damage to the bark, and weeping resin. I have made a point of investigating hundreds of these trees, when I can (though I have seen thousands) and they all show the same symptoms. Looking up the symptoms, this is gummosis, with the advice being to remove the infected tree from the environment. Well, this presents a certain issue seeing as just about 99% of the trees I see are thus afflicted. The damage, to be clear here, is eye-watering: in many instances the bark has just peeled off and lifted right away from the heartwood, to the extent that it is obvious the tree will soon be dead. Amazingly, many of these trees are yet in reasonable leaf - though I now note the decline of local individuals on a weekly basis - causing me to wonder how recently the damage has occurred. The extent of this is so bad that I came here expecting to see a lot of discussion about this. I will be amazed if any of these cherries are still around two years from now.

 

It gets worse, however. The more I have learned to recognise defoliation, crown die-back and the various pathologies unique to each species, the more I see it. Go into any residential street in Portsmouth and you will see rowans with half the branches completely dead, sycamores displaying die-back, purple-leafed plums horribly defoliating, hazels with dead branches. Any road. I've surveyed a few roads near my workplace for the damages particular to each tree - I would conclude that about 80% have something seriously wrong with them, the majority displaying horrible bark damage near to the base. These are verge trees, however, for the most part, so I suppose it could be reasoned that they aren't in an optimum location, even though some have been there at least thirty years or more. (It is true that the more asphalt surrounds the tree, the worse they appear - the alders around the nearby Sainsbury's all look like they've been hit by lightning).

 

So I have also surveyed local parks and recreation grounds. If anything, the situation is worse. Some dead trees here and there, some half-dead (with that reduction in crown where the leaves appear to demarcate a smaller tree within the halo of dead branches), but when I walk among the trees I find that 90% show serious bark damage just above ground level, also with a kind of lateral eating away of the bark - through cambium and xylem layers to the heartwood. I take photos and am not selective because I don't have to be. This is alders, poplars, ash and aspen, and some absolutely massive weeping willows where the bark of the tree looks like someone took a blowtorch to a candle. There are two Eastern black walnuts with some minor leaf loss but nothing very worrying, unlike the English walnuts, which are starting to look quite ill.

 

I noticed when I am in Fareham that the plane trees all along the town centre have stunted and twisted leaves. There is a large-leafed tree (I think it's a foxglove tree) at the end of the pedestrianised area which is showing severe die-back.

 

There's an avenue in Portchester (Birdwood Grove FWIW) with a shaded walk down to the sea which is planted with (sweet) chestnut trees. There's been an amazing harvest there every year and the trees look fine - until you inspect the trunks (through the nettles) and find that every single one has that blowtorched candle effect.

 

I'm watching all the lime (tilia) trees in my neighbourhood. Some are fine, though I can't access the trunks (either because they're sprouting like crazy from the base or because they're behind hedges), but others are displaying die-back. Oaks, too. I passed a grand old pedunculate today which had been chopped in half; the remaining leaves were pretty pathetic and it was obvious the tree will be dead soon. I stopped my car, jumped out and assessed the trunk: mounds of particulated wood from insect infestation, black sap running down the trunk, and two large sections above the roots where there was only dead wood on display, no bark. On its own, this is simply a dying tree. But taken alongside everything else, it seems like trees en masse have lost immune function. If there's a pest or a disease that can attack a tree, it's just party time.

 

I've phoned tree surgeons and they seem oblivious, unaware even of the plight of cherries (which is amazing to me). I've spoken to park wardens, tree wardens - they know of a disease afflicting a particular tree, but then they simply shrug.

 

It makes me wonder about all the piptopori I was picking from birches last year. I now suspect their immune systems were compromised because these were harvested from standing as well as fallen trees.

 

Can anyone verify, dismiss, or explain what I'm seeing?

Edited September 6, 2015 by Quercus Robert

[treequip]

A lot of the problems you describe are just nature levelling things out, the problems with the flowering cherry is a good example, its a non native over hybridised mess. HC is questionable native, probably an introduction

 

Nature says 3/10, must try harder

 

Your personal life cycle rotation is far to quick, pests and diseases move in cycles measured in decades or centuries, DED is a good example, there is good evidence it a repeat of an event that happened centuries before.

 

Don't sweat what you cant change, we spent fortunes in time and money sanitising DED, phytopthora and the like, all to no effect whatsoever.

 

Plant native species with a diverse genetic provenance.

[Steve Bullman]

there is good evidence it a repeat of an event that happened centuries before.

 

 

interesting, any links to more info on that?

[treequip]

From memory it was part of a study of pollen records.

 

They took core samples in peat deposits that provided stratification evidence.

 

There was a huge furore about DED, bans on movement order and such like. They had found substantial absences of Elm pollen over periods of time that lead them to conclude that Elm was absent for an extended period.

 

I remember being secretly quite pleased at the time, I took it to mean there would be plenty of big climbs and fells in the offing, young and gung ho, break out the 076

[Yournamehere]

Oliver Rackham delved into the historic periodicity of DED in 'Woodlands' the Collins New Naturalist book what he wrote and the encyclopedic 'Ancient Woodland' what he also wrote.

[Mick Dempsey]

As for the op.

Have you just qualified or finished some kind of tree biology thing.

I ask because it may be that you are seeing these things with new eyes. It was perhaps ever thus and you just didn't notice.

A bit like this scene from "They Live"

[ame]

[/ame]

[Quercus Robert]

Yes, it is very much like I'm wearing Roddy's glasses (RIP).

 

Although, I'm not convinced by this being either a weakness of cherries (this could also apply to the purple-leafed plums IMO, but not to oaks, sycamores, walnuts, ash etc), or an affect of new knowledge - simply because it is afflicting so many trees. It's more than half; quite easily more than half, unless it's totally normal for all trees to have extensive sections of bark completely eaten away. I'm also noticing more severely-depleted and scorched crowns with each passing week.

[Quercus Robert]

Hi. Update:

 

I have continued examining trees of every kind in every location possible, including woodland.

 

Today I went to the forest of Bere. I had a dual purpose as I was also seeking birch polypore (in the end I found a beefsteak fungus on a rotting chestnut stump).

 

I want to be unconditional and categoric here: almost all the chestnuts, beech, birch and oak show incredible bark damage, some high up, others at the base, with absolutely incredible amounts of heartwood on show. Some of them appear almost circled. Sometimes the foliage is OK, other times there is massive dieback. These trees are dying.

 

I can see that the forestry people have been out removing and felling a lot of dead and dying trees - away from the paths where families walk with their dogs and children. Move 100-200 metres in from the paths and they've been pretty busy. So, I assume this is a recognised problem. I don't think there's any point talking about cherry gummosis, ash dieback, leaf miners on horse chestnuts, AOD etc etc; whatever this is, it's cross-species, i.e. it's environmental, and it's causing trees to lose whatever resistance they have to naturally-occurring pathogens.

 

This is not strimmer damage or compaction in the middle of woodland; it isn't drought or deluge or heatwave or a cold summer or oscillating hot-wet weather. It's not restricted to urban areas. I have a cherry, two sycamores and a cultivated plum positively dying in my back garden. To the front there are limes, oaks, birches and those ubiquitous purple-leafed plums, all dying back (looking at the trunks of these usually confirms what I expect to see: nasty trunk damage along with insect infestations - always nice to see a few thousand woodlice and a couple of hundred earwigs fall out when I tug at a piece of cracked bark). Woodland environment: different trees but exactly the same situation. The public aren't seeing this because they're either blind or stupid.

[Paul Barton]

Can you post photos, or a link to some?

[Kveldssanger]

I have noticed a lot of poorly trees as well - limes, horse chestnuts, oaks, ash, ornamental cherries, birch, hornbeam, a few field maple. Everything does seem to be struggling.

 

Here's my thoughts:

 

1. Horrifically poor genetic provenance / pool - when man enters (virgin) forest with timber production in mind, what trees are the first to go? The ones that are best. The best trees are removed. Man ignores the 'naff ones. From the offset, we are altering genetic pools, removing the trees that should be reproducing, and facilitating reproduction of less 'optimal' specimens. At times, man ever clear-fells an area to plant with non-native stock with genetic progeny that would very likely not have 'made it' naturally. We throw the plasticity of forests out of whack, remove the best specimens, fragment, damage, and plant new trees in the wake of the old ones. Coppice woodlands are time-locks due to a lack of natural regeneration - it's all vegetative (layering, suckering, etc). Seed banks are permanently destroyed. We introduce game to forests. Damage is rife, across the entire spectrum of woodland characteristics. Heck, lots of our cherries in woodlands come from jam factory seeds, and our ash stock 'aint much better (thank the rapid planting in the 70s on farmland for that!). Chalara will certainly hit harder than it would if we had actually considered genetic progeny back then with our ash.

 

2. Man acting as a vector for disease - transport brings over diseases far more rapidly than they would ever be able to naturally succeed (Asian Longhorn Beetle, for example). What would have taken decades takes mere years, and what may never arrive can do. Phytosanitary measures are lacking, despite the good intentions of many, and the lack of desire to limit international and intranational trade and transport will only fuel further issues down the line. Diseases may become pan-mundi, so to speak. All the while, man is planting genetic stock that would not make it through the proper means of species competition and 'survival of the fittest'. Recipe for disaster, no? And we're not even talking about urban areas - genetic stock of our streets is probably shocking.

 

3. Pollution - soil acidification, salts, aluminium, etc etc etc. Industrial waste. Dumping chemicals in river 'by accident'. Fracking, underground coal gasification, cars, planes, water vapour, CO2, methane... Nitrogen, too much nitrogen on already suffering trees = so very bad. Trees aren't designed for such rapid adverse change. Pulling the carpet out from beneath their feet (roots), no? We never learn as a species.

 

4. Lack of natural regeneration (woodland and urban) - "I don't like this native oak that is growing in my garden, let me take it out and replace it with a nice japanese maple". trees that are making it naturally are neglected in favour of nursery-bought trees. Want to make a difference? collect local seed, grow that seed, and plant it locally. Not to mention seedling recruitment in woodlands - over-browsing, humans trampling through stuff in the pursuit of experiencing natural beauty (whilst trampling it all down at the same time), disease, pollution, fragmentation.

 

Everything is wrong. It's so bleedin' obvious as well, yet we still harp on about how we can do something about it. Well I don't see that, if I'm honest. Too many people, too little care. We'll be watching the demise from our TV screens, not even bothering to look out the window.

 

Reminds me of the Milgram Experiement, but with our very natural world in the chair instead of another human. Cries of "STOP!" are ignored, even if we recognise we need to stop.

 

/rant.

 

Just my mental notes. Probably little coherency.

Edited September 20, 2015 by Kveldssanger