Diseased cherry tree in garden

[Cotham Marble]

Originally Posted by animartco

The root you describe sounds like the cherry's own, and the fungus being a dead wood fungus is very strong evidence for a natural death.

That is a misstatement of what Armillaria is. While Armillaria does indeed digest dead wood, once it has developed rhizomorphs (and what Herd has photographed are undoubtedly rhizomorphs) the fungus becomes 'infective', with the rhizomorphs actively penetrating the roots of living trees. If the tree is a susceptible species, young, or under stress then it is liklely that the armarilla will kill it, and then use the nutrient of the dead tree to produce more rhizomorphs which extend to the next living victim. Anyone with Armillaria in their garden should take it seriously and take all precautions to limit it's spread - it won't stick to single garden and every woody plant within 10 metres of existing rhizomorphs should be considered to be potentially under threat.

CM

[Cotham Marble]

Originally Posted by Jez

One way to keep the beasts at bay is to place butyl liner or similar in borders or around specimen trees vertically at a depth beyond huney fungus limits. I forget the depth, though it can be found at the RHS site.

Actually the RHS have cast doubt on the value of plastic barriers, though I don't think the RHS site explains why. The problem is that there is no absolute depth at which the rhizomorphs can extend to, the limit is really only on how friable the soil is. Of course in the UK we don't have many areas where dense subsoil is more than 50cm below the surface and the rhizomprphs wil not usualy be found below that, but if lighter or uncompacted soil extends below 50cm, then so can the rhizomorphs. And that's where the problem with putting in vertical barriers comes up - because you have to dig into the subsoil, you actually make it friable. Even if the plastic is bedded into the subsoil, because te barrier extends to the surface water penetrates down the barrier, encouraging soil bacteria and invertebrates, which then proceed to build a friable soil below the barrier, providing an eventual ingress for the rhizomorphs. The only reasonably effective barrier against Armillaria rhizomorphs is an area of annually worked deep cultivation.

CM

[Jez]

Here's a link to resistant and susceptible plants.

http://www.rhs.org.uk/RHSWebsite/fil...ecd3ed1ed4.pdf

[animartco]

Hi Cotham Marble. I feequently find those rhizomorphs around dead trees, but they do no obvious harm to healthy living trees. If the Cherry tree was thirty years old it was past its use by. However it might be better just in case not to replace with a Malus. I advise try something completely different; amelanchier say, if you want early blossom, but better something that flowers later.

[Herd900rd]

Originally Posted by animartco

Hi Cotham Marble. I feequently find those rhizomorphs around dead trees, but they do no obvious harm to healthy living trees. If the Cherry tree was thirty years old it was past its use by. However it might be better just in case not to replace with a Malus. I advise try something completely different; amelanchier say, if you want early blossom, but better something that flowers later.

What is amelanchier in English? If the rizomorphs were alive, wouldn't they sprout some new shoots if put in water (see one of the pics I posted of them)? The ones I have put in water in a little plastic tray so no sign of life.

[Cotham Marble]

Originally Posted by Herd900rd

If the rizomorphs were alive, wouldn't they sprout some new shoots if put in water (see one of the pics I posted of them)? The ones I have put in water in a little plastic tray so no sign of life.

Rhizomorphs do not have the same characteristics as the roots or shoots of vascular plants, even though they look like plant roots. It is of course possible that desication following your digging them up has killed all the living cells in these particular rhizomorphs but even if they are alive you would need to provide nutrients to stimulate growth. Think more in terms of growing animal tissue in a test tube than taking cuttings from a shrub or tree. Fungi are not plants but a seperate type of organism that is actually genetically closer to animals.

CM

[animartco]

Hi Herd 900. Amelanchier? It's sometimes called snowy mespilus. Not much of an improvement! but it is a lovely slender dainty little tree with masses of white blossom fairly early in spring, and pretty leaves.

[hamadryad]

The Armilarias are ever present in soils, they can in some cases cause a lot of demise within a graden or tree population, especialy weak senescent trees like an old cherry. armillatox has been banned for this purpose so forget it and it isnt a very "holistic" approach iether.

as for resistent species i can assure you there isnt one, it is the health and vitality of the tree that holds off the colonisation of these reapers. they are an mportant organism in the arboreal system and like a predator take out the sick/dying genes from the pool.

Maintaining a healthy rhizosphere is key to fending off armilaria in YOUR soil, and any ornamental variety will be of poor genetic stock against this often strong pathogen, its pathogenicity is still a raging debate. there are many forms too.

if you really want to plant a new tree i would suggest finding a truly forward thinking nursery who not only advertise mycorrhizae inocluated stock but are ACTUALY able to achieve it! via a holistic transplanted system where a sapling is planted in ground already associated with the species and its associated mycorrhizaes.

This is a very effective system of defense against the armilarias.

Just to add my thoughts to this post.