Voles attacking apple tree?

[hellomabel]

Hi.

I have four three-year-old apple trees, all planted on a north-facing slope in a valley in East Cornwall. I gave them all deep mulch (including old carpet), cleared the pervasive bracken away and erected seven-foot-high wire netting cages around each to ward off deer (I have seen roe deer around). This year for the first time three of them cropped and look healthy.

Sadly, the remaining one ? although the same variety as one of the others ? briefly showed leaflets and buds in the spring, which then withered and died. I could see no telltale bites, scrapes or insect infestation, or any canker so I left it alone to see whether it would regrow the leaves (we had a very dry April, which might have had an effect).

This week, with no signs of growth, I scraped bark away and then snapped twigs off and it's all brown inside. I'm no expert so I can't be sure but I suspect the tree is dead.

Somebody suggested either honey fungus as the cause (what does this look like?) or voles burrowing underground and nibbling the roots. I have removed all the old carpet and mulch but can see no holes. We do have holes in a bank about 30 feet away and the cat has caught a few rodents in the garden, so it is quite possible.

I have three questions:

1. How do I check to see if voles are the culprit?
2. How do I get rid of them?
3. How do I stop reinfestation?
4. What else could it be if not voles? I am convinced the cause is either airborne or underground, as there is nothing visible topside. I do have a black mulberry about 40 feet away which has canker, but one of the other apple trees is closer to it and appears fine.

It is a damp climate but the trees are two old local varieties so shouldn't suffer. The soil is on the acidic side but otherwise fine. I had a soil expert from a local university analyze the soil before I bought the land and she produced a long list of ingredients and pronounced it highly suitable (she also has an orchard so I trust her knowledge). Unfortunately I have lost touch with her!

Thanks for any tips and suggestions.

[echinosum]

Honey fungus produces fairly large toadstools in clumps and thick bootstrap-like mycelium by which it spreads. You'd see it if the tree was already dead. 'Armillaria - Wikipedia, the free encyclopedia'

It's unlikely it would kill a new fruit tree if it wasn't already in your garden killing lots of other stuff.

If the tree is just 3 years old, and died, you should be able to pull the tree up fairly easily and have a look at the roots, and see what is going on. There's one area of my garden, along a south facing wall, where I'd like to grow fruit trees, but I've tried a few times and they just die when I try. The roots never get going. I've decided it must be something in the soil, building waste or something. Maybe the tree you were given was no good. Perhaps it was potbound. Maybe there are insect pests (eg vine weevils) eating the roots. Voles seems unlikely.

[songbird]

drought can kill a newly planted tree. carpeting and mulch can prevent moisture from leaving the soil but it can also soak up moisture or form a crusty layer that sheilds the soil from soaking up moisture too.

some mulch is ok, but carpeting might be enough to suffocate the roots of a tree or otherwise limit the growth. remember the soil and roots need oxygen too (unless the plant is suited to wetland/water habitat, which isn't the case for apple trees).

voles often will leave tracks through the grass that you can see where they are running. also you can trap them with mice traps and that will tell you if you have them about. you can use peanut butter, old bacon ends, as bait (they are omnivores). they look nothing like a mouse. you'll know if you catch one, they are dark grey and shaped like a plug not pointed like a mouse and they have tiny black teeth.

songbird

[hellomabel]

Thanks for the tips. I doubt the soil is too dry (it's a damp area) and the other trees haven't suffered at all.

The vole info is particularly useful, but how big are they? Mouse-size or bigger - a year ago I saw a rodent that was plug-shaped but much bigger. There's no grass in the area - it's all tall weeds like bracken (hence the need for weed-suppressing matting).

Thanks again.

[songbird]

hellomabel wrote: ...

4-6 inches. shaped like a plug. heftier.

songbird

[hellomabel]

Thank you. That sounds like what I saw.

[echinosum]

Because there are so many things that can cause your fruit tree to die, and voles would be a very rare reason in England. Voles do eat succulent roots, like bulbs and potatoes, but they don't normally eat woody tree roots. When they do damage fruit trees, try do it by ring-barking. But that doesn't happen often in England, if your tree had been ringbarked by small animals, then here in England it would be much more likely to be rabbits. Voles is much more of a garden nuisance in America, where they will rearrange all your garden bulbs, and eat most of them, most years.

Voles nevertheless are extremely common in England, they are basically everywhere if you are anywhere near fields or open country. They form

90% of owls' diet, they are that common. I caught two voles in traps in our kitchen just the last two weeks. I've seen them in the compost bin. I've seen them pinching the seeds from the bird feeder that the birds drop. I've found their nests in the shed and the garage. I regularly hear owls, so they must be hunting the voles hereabouts. But they have never damaged any of our trees.

[echinosum]

Some more research. There are two common kinds of vole in Britain (plus a few rarer ones). After a bit more research, I read that the one that might do tree damage, by chewing bark of young trees, is the field vole, Microtus agrestis. What they mostly eat is grass. They are more likely to damage the bark of young trees if the tree trunk has long grass around it. The other common vole is the bank vole, M glareolus. Bank voles mostly eat fruit, nuts, leaves, seeds and a few small animals.

[hellomabel]

Thanks for the helpful answer. To take your points individually:

ech> My late mother had a similar problem with a black mulberry, likewise

In my defence there is a grass-free mulched ring around the tree so it's not due to lawnmower damage!

ech> Bearing that in mind, ie, unless you do something drastic it is probably > doomed anyway

If I do need to chuck it, would it be safe to plant another one in the same hole or do canker spores linger in the soil?

ech> what I would do would be to try drastic pruning to see if it would

So prune in, say, November? And should I apply anything to the stumps to stop any bleeding? I'm assuming there's no point in giving the tree a feed at the same time as it will be asleep, but what about in the spring?

Thanks again for the helpful info.

[echinosum]

Prune once you can tell it is dormant, because the leaves are properly falling off, whenever that is. In mild autumn, it may take a little longer. No hint of autumn on mine yet, we are still picking berries...

RHS says don't do anything about any bleeding, but pruning in the dormant period it shouldn't bleed much.

In general mulberry trees shouldn't need feeding. With that Victorian hardcore, and deep tree roots, there should be plenty of good stuff for it down there. And in general one doesn't feed sickly plants.

I think if you are replacing a tree with another one of the same type, it is always a good idea to plant it somewhere slightly different.

[hellomabel]

Thank you. I'll try chopping it before I give it the final chop though.