Unknown fungus on my apple tree

[Chamber]

Hi,

I recently bought a house with a number of apple trees in the garden. On of them had an old hanging basket attached, and the tree had grown around the chain. I removed the chain, but obviously damaged the tree a little as I now have an unknown fungus growing over the wound (see attached photo).

I'm not much of a gardener, but don't want to loose this or the other trees in the garden.

If someone could take a look at the picture and give me any advice on what to do to kill it off, I'd be very appreciative.

Thanks,

Chris

[Leif]

I think it is too young for most people to id, but it might be Phellinus pomaceus. It may develop into a bracket. You could try asking on Association of British Fungus Groups. I do not know how to treat it. A bracket like that is simply the fruiting body, with the main part of the fungus in the tree. Given where it is, I suspect you might be best to chop the tree below the growth, and hope it sprouts new growth. Most deciduous trees do, though I am not sure about apple. Given the fungus, you might just end up with fungus on the cut end if you cut too close. Anyway, I suggest you get a second opinion. Maybe there is a less aggressive solution.

[FB.]

On such an old tree, any major pruning should only be done while the tree is dormant. Someone about a mile from me had a handful of beautiful apple trees in their garden, but which were getting a little on the large side. They pruned them all hard about August last year. They are now all dead from the shock.

Even if you prune the tree to try to remove the fungus, it might well be all through the inner wood and come back. You'll also find that the tree may well never be able to become an attractive shape again.

The fungus is probably there as a result of infecting the huge wounds where big branches were removed several years ago; you can still the the inner wood of the tree which the tree hasn't been able to grow over. The inability of the tree to quickly heal such a large wound is what let the fungus in. pruning wounds should, ideally, be no more than two inches and it is therefore wise to anticipate a troublesome branch and remove it before it gets too big to heal.

Personally, given the age of the tree and position of the fungus, I'd be inclined to leave it alone and enjoy the tree while it remains alive - which could be many years. Given time, the tree may be able to wall-off the fungus, although at a price of becoming hollow inside and therefore structurally weakened.

I would suggest a couple of light compost or manure mulches per year, in order to make sure the tree has a good, balanced supply of nutrients to try to heal itself. Synthetic pelletised fertilisers and liquid feeds are just not the same benefit as composts and manures.

[Leif]

At the risk of stating the obvious, what I was suggesting is known as pollarding, and it is an ancient technique for growing branches suitable for baskets etc. A Google did suggest that apple does not take well to pollarding, and as FB says, only do major pruning in the dormant period.

Adding to my earlier comment on the fungus, the brown pore surface is consistent with the Phellinus genus, and P. pomaceus grows on trees in the Prunus genus. It is not particularly pathogenic i.e. does not necessarily kill the tree.

[FB.]

Adding to my earlier comment on the fungus, the brown pore surface is consistent with the Phellinus genus, and P. pomaceus grows on trees in the Prunus genus. It is not particularly pathogenic i.e. does not necessarily kill the tree.

The fungus is already in the tree now, having got in through a large pruning wound, so even if it is pathogenic, the fact that it's got into the trunk means that it can't be cured.
However, old apple trees of vigorous (often triploid) varieties seem to have a remarkable ability to cling on to life by simply outgrowing the pests and diseases.
So the vigorous varieties tend to be able to live with the problem for a very long time; co-existing with a whole load of parastic fungi feeding on them, and often the tree ends up being removed by the owner simply because it became disfigured/mis-shapen or, quite often badly leaning, rather than actually dead.

The following thread showed an estimated 90-year-old tatty tree with a hollow and half-missing trunk, but it's a vigorous triploid (Gascoyne's Scarlet) that's otherwise healthy.

Link here:
http://www.growfruitandveg.co.uk/gra...unk_67241.html

Notice how the tree has grown bark over the edges of the missing trunk areas; it has walled-off the dead bits (which have since rotted away) but where it has walled-off the dead bits, it produced bark underneath which acted as a barrier to disease entry.

As with "Chamber's" tree at the start of this topic, the removal of a large branch is what let the fungus in because there was no bark present. However, as veggie's tree shows: the tree, if vigorous, will often find a way to cling on to life.

[Leif]

The fungus is already in the tree now, having got in through a large pruning wound, so even if it is pathogenic, the fact that it's got into the trunk means that it can't be cured.

An interesting an informative post, and it probably cannot be removed apart from chopping below the wound. Perhaps the OP could consider the fungus to be another ornamental 'plant' in the garden. Regarding pathogenicity, some fungi are very aggressively pathogenic, honey fungus being a common example. Others are parasitic, but do not really harm the tree, or at least not much. They get in at a wound site, where the tree is weakened, but they cannot really progress far into the healthy tree tissue. Laetiporus sulfureus, aka Chicken of the Woods, is an example of the latter. Trees produce some very toxic chemicals that repel most fungi, until they die, and then gradually as the chemicals break down, fungi move in and reduce it to humus.

I remember a beech tree in the New Forest with some lovely Volvariella bombycina growing from the side. That is one of the most beautiful mushrooms found in this country. Anyway, the tree was completely hollow, maybe a meter wide, and all but a 6" outer area had gone, but the top growth was very healthy looking with plenty of leaves. V. bombycina is also found on apple trees, although I've never seen it on that host.

[FB.]

Regarding pathogenicity, some fungi are very aggressively pathogenic, honey fungus being a common example. Others are parasitic, but do not really harm the tree, or at least not much. They get in at a wound site, where the tree is weakened, but they cannot really progress far into the healthy tree tissue. Trees produce some very toxic chemicals that repel most fungi, until they die, and then gradually as the chemicals break down, fungi move in and reduce it to humus

Yes, many old trees become hollow as a result of the inner wood having long since died. The fungi simply take advantage of the long-dead wood. By not allowing too many large wounds, the hollowing-out of the tree can be delayed, therefore delaying the day when the tree suffers a major breakage as a result of the weakened structure.
I tend to think that honey fungus (Armillaria sp) tends to prey on plants which are already stressed for one reason or another (whether it be old age, other pests or diseases, or the soil conditions not ideal for the tree or particularly good for Armillaria).

In any case, the fungus in that picture certainly doesn't look like Armillaria. As you say: cutting back hard might get rid of it, but since the whole of the wood deep in the trunk will be dead (especially some of the xylem and phloem tissue formerly connected to the now-removed branch), it's possible that fungal mycelium and hyphae already extend deep down and may be some distance from the point where the fruiting body is appearing, in the same way as a plant's roots can be some distance from where the plant is growing.

[Leif]

I tend to think that honey fungus (Armillaria sp) tends to prey on plants which are already stressed for one reason or another (whether it be old age, other pests or diseases, or the soil conditions not ideal for the tree or particularly good for Armillaria).

The reason why Armillaria species (Honey Fungus being one species) are so aggressive is that they send out underground rhizomorphs which search for the next victim. Other fungi have to rely on a weakness in the tree such as a wound, to allow the newly germinated spore to feed and grow. But Armillaria can attack a healthy tree, using the rhizomorph to sustain the attack until it can enter the target tree, and feed from its wood.

In any case, the fungus in that picture certainly doesn't look like Armillaria. As you say: cutting back hard might get rid of it, but since the whole of the wood deep in the trunk will be dead (especially some of the xylem and phloem tissue formerly connected to the now-removed branch), it's possible that fungal mycelium and hyphae already extend deep down and may be some distance from the point where the fruiting body is appearing, in the same way as a plant's roots can be some distance from where the plant is growing.

No I was not suggesting it was an Armillaria species.