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Honey fungus (Armillaria mellea and closely related species) is a fungus that lives by decomposing wood.

1 Honey mushrooms

The fruiting bodies of the fungus are mushrooms that grow on wood, typically in clusters. The cap is 3-15 cm in diameter, typically has a honey yellow-brown color, and is covered with small dark scales. The stem has a ring.

Honey mushrooms are edible and considered very tasteful, but certain species can lead to temporary stomach problems, especially when eaten raw. (Warning: do not rely on Wikipedia alone to identify mushrooms for consumption)

2 Honey fungus as a plant disease

Honey fungus is a potentially fatal pathogenic organism that affects trees, shrubs, woody climbers and, rarely, woody herbaceous perennial s. Honey fungus primarily lives on dead and decaying woody material. Most species are harmless, although one or two types are also able to attack living plants.

Honey fungus spreads from dead wood such as roots and stumps by means of black root-like rhizomorph s ('bootlaces') at the rate of around 1 m a year, although infection by root contact is also possible. Infection by spores produced by honey fungus toadstools (the fruiting body of this fungus) is rare. Rhizomorphs grow relatively close to the soil surface (in the top 20 cm) and invade new roots, or the root collar (where the roots meet the stem) of woody plants. An infected tree will die once the fungus has girdled it, or when extensive root death has occurred. This can happen rapidly, or may take several years. Infected plants will deteriorate, although may exhibit prolific flower or fruit production shortly before death.

Initial symptoms of honey fungus infection include the dying back of leafy branches or failure of leaves to appear in spring. Black bootlace-like strands appear under the bark and around the tree, and fruiting bodies grow in clusters from the infected plant in autumn and die back after the first frost. However these signs do not necessarily mean that the pathogenic (disease causing) strains of honey fungus are a cause of plant decline or death, so other identification methods are advised before a diagnosis is made. The presence of thin sheets of cream coloured mycelium, giving off a strong smell of mushrooms, beneath the bark at the base of the trunk or stem, sometimes extending upwards, or a gum or resin exuding from cracks in the bark of conifers, indicates that honey fungus is a likely cause of problems. If further confirmation is required, it is advisable to seek the advice of a qualified tree surgeon.

3 Preventing infections

Honey fungus can be prevented by removing tree stumps or other dead woody material such as roots from the soil, for example by mechanical stump-grinding. Killing stumps chemically is often not sufficient. Healthy growth of woody plants in the garden should be encouraged by correcting any drainage problems and adequate feeding and mulchIn agriculture and gardening, mulch is a protective cover placed over the soil, primarily to modify the effects of the local climate. A wide variety of natural and synthetic materials are used. Mulch is used for various reasons: to adjust soil temperatureing. There is often concern that honey fungus can live on woody mulches, especially when the rhizomorphs are seen under the mulch. It is in fact quite safe to use woody mulches where honey fungus is present.

If the presence of honey fungus is confirmed, all dead or dying woody plants should be dug up and any roots or stumps removed. If removal of a stump is impossible, the stump can ground, or chipped, by a contractor. The resulting woodchips should be burned or disposed of outside the garden, not used as a mulch. As a last resort, a stump can be treated with ammonium sulphamate (a stump killer sold as Amicide or Root Out) However this is not an approved organicOrganic gardening is gardening, without using man-made chemical pesticides or chemical fertilizers. It is said by some of its supporters to be more in harmony with nature. Organic gardeners emphasise the importance of "feeding the soil, not the plant". product, and should not be used by registered organic growers.

If plants in a hedge are infected, the plants either side of those contaminated should also be removed. Areas affected by honey fungus should be replanted with non-woody species, or by species showing resistance such as yewYews are small coniferous trees or shrubs of the genus Taxus in the Yew family Taxaceae. They are relatively slow growing and can be very long-lived, and reach heights of 1-40 m, with trunk diameters of up to 4 m. They have reddish bark, lanceolate, flat, (Taxus baccata), CornusThe genus Cornus is also known as the dogwoods, with about 30-50 species depending on taxonomic interpretation. Most species have opposite leaves, but alternate in a few. The fruit of all species is a drupe with one or two seeds. Flowers have four parts., beechFor the beech tree, see below. Beech is also the name of an aircraft manufacturer that was purchased by Raytheon. Fagus crenata Japanese beech Fagus engleriana Chinese beech Fagus grandifolia American beech Fagus japonica Japanese blue beech Fagus longipe (fagus) and HebeHebe Scientific classification Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Scrophulariales Family: Scrophulariaceae Genus Hebe Species Hebe acutiflora Hebe affinis Hebe albicans Hebe andersonii Hebe buxifolia Hebe cupressoides Heb. Fruit trees and bushes should not be grown on areas known to be infected, and particularly susceptible species such as birchmany species ''see text and classification Birch is the name of any tree of the genus Betula in the family Betulaceae, closely related to the beech/ oak family, Fagaceae. These are generally small to medium-size trees or shrubs, mostly of northern tempera, cypressCypress is the name applied to many plants in the conifer family Cupressaceae (cypress family). Most plants bearing the common name cypress are in the genera Cupressus and Chamaecyparis but several other genera in the family carry the name: Cupressaceae C, lilac, pine, privet, walnut and willow (Salix) should also be avoided. Without host plants the fungus will eventually die out.



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