Joined: 30 May 2006 Posts: 2151 Location: West of Ireland
Posted: Mon Aug 18, 2008 12:03 am Post subject: Honey fungus "boot-lace", cause, treat, cure.
Honey fungus "boot-lace", cause, treat, cure.
Many trees, shrubs and a few "woody" perennials including.....
Apple trees both crab and eating varieties.
Cherry trees (Prunus) both flowering and fruiting are particularly susceptible.
Cypresses including Leylandii
All year round.
Signs and Symptoms. Above ground.
Plants attacked by Honey fungus have their roots weakened, weak roots are unable to support growth, this results in plant leaves turning yellow, wilting and dropping.
In springtime leaves may fail to appear, or if they do they emerge they will be smaller than usual and yellowed or off-colour.
Shoot and branch development will also be poor and shoot dieback is common during the growing season on infected plants.
In autumn, the plant may exhibitits autumn leaf colours prematurely, followed closely by premature leaf fall.
Depending on the initial strength and maturity of the plant before the disease is contracted, the plant may die quickly (one season) or over a period of years.
Trees affected by Honey fungus which are in senescence (about to die) often produce their greatest ever show of flowers and fruit just before dying.
On trees, especially conifers, the base of the trunk may crack and begin leaking a sticky gum-like substance.
Bark on the trunk appears to separate from the wood beneath for several feet upwards from the base of the tree. Peeling off a little of the bark will reveal a white fungal growth (mycelium) with a strong tell-tale smell of mushrooms.
. Honey fungus mushrooms found at the base of infected plants, photo / picture / image.
Yellow-brown or honey coloured mushrooms are often produced at the base of the plant each autumn, hence the common name Honey fungus. These fungi custered in their hundreds beneath mature trees, possess a collar-like ring on the stem below the cap just above a honey-coloured downy stem.
As if the disease itself was not frightening enough, both the mushrooms and the exposed mycelium on the trunk of infected plants are reputed to glow spookily in the dark.
. Honey fungus symptoms, photo / picture / image.
Black "boot-lace" like growths (rhizomorphs) branch out underground from the base and roots of infected plants, hence the other common name boot-lace fungus.
These rhizomorphs can resemble old roots, but if pulled at the black outer coating breaks away to reveal white fungal growth with a strong smell of mushrooms.
Honey fungus or boot-lace fungus is a disease occurring worldwide caused by up to eleven varieties of the fungus Armillaria.
The variety affecting most broadleaved trees and shrubs is Armillaria mellea.
The variety affecting most conifers is Armillaria ostoyae.
This is a very serious disease of trees, shrubs and "woody" perennials.
Because the fungal "boot-lace" like growths invade nearby plants below ground and through the soil and roots, it is like a form of creeping death with lots of potential for tree-to-tree spread.
If any of your prized plants become infected they may take a number of years to die, all the while looking sick, while you agonise over what you did wrong.
Organic or cultural control. Prevention.
Because Honey fungus thrives on old rotten tree stumps and spreads from them, you should avoid planting near these hosts. This means be careful of planting too close to or into old wooded areas and ditches. Also avoid sourcing soil for your garden from these locations.
Conifers are particularly susceptible to Honey fungus if planted into soil where broad-leaved trees once grew, so try to avoid such a sequence.
In short, when preparing your new garden for planting, ensure you remove all old stumps, dead plants and pieces of wood as they may harbour the disease.
If there are existing healthy trees/plants on site when you are house building/ garden creating, you should prevent injury to their roots by fencing their root system off from heavy machinery traffic during construction. Injured roots of trees/plants leave them open to Honey fungus invasion.
Planting trees and shrubs and "woody" perennials regarded as resistant to Honey fungus are reccommended, these include.....
Strong healthy plants have a good chance of fighting off the advance of Honey fungus, so it will pay you to keep your plants fertilised, mulched and watered regularly. However, don't overdo the artificial fertiliser, as this can promote excessive amounts of soft growth which is easily invaded by the fugus. Slow release artifical fertiliser or well rotted compost is your best bet.
If Honey fungus is found in your garden.
Cut the plant down, dig out the stump and as much of the root system/surrounding soil as possible. Be aware that the fungal "boot-lace" like growths (rhizomorphs) found in the soil can branch out underground for many metres to a depth of 70cm.
All saws, spades and other tools used in this process of Honey fungus removal should be washed afterwards and wiped down thoroughly with alcohol.
Many gardeners isolate the infected area by installing a encircling vertical barrier of builders film, radon barrier or pond liner to a depth of 60-100cm.
In the case of one hedging plant succumbing to Honey fungus eg. Griselinia, you will prevent the spread along the hedge by removing a healthy plant on each side of the infected one.
When replanting after Honey fungus select from the list of plants regarded as resistant, listed above.
Soil areas infected by Honey fungus were in the past drenched with diluted Jeyes Fluid or Armillatox to sterilise the soil. These are not currently approved by the EEC for use as a soil sterilant, pesticide, insecticide or herbicide within Europe. These products still work as honey fungus control although they are marketed as suitable for cleaning drains, patios only.
Irish home delivery.
UK home delivery.
US home delivery.
Video. An example of Armillaria (Honey fungus) rhizomorphs, and how one gardener feels about it.
If the video is missing, first check that you have the required player Adobe Flash Player installed on your computer. If you wish to download and install it , it can be got here.
If the video is still missing after you have installed Adobe Flash Player, then we suggest you please inform us by emailing here info(at) irishgardeners.com change the (at) for @
Please note that Irishgardeners.com does not advocate the removal of fungal, animal or insect life, instead, this forum encourages wildlife preservation. However, there are occasions where a wildlife becomes a problem within the garden for certain people. Be aware that wildlife is a link in the chain of life, benefiting something or someone down the chain. Please at least think about this before you remove wildlife from your site.
(DISCLAIMER: The control methods are suggested here as a matter of general information. Under Irish and EU law it is illegal to use any preparation as a pesticide/fugicide/herbicide that is not approved for such use. The author and the website accepts no responsibility for how a user may mix, use, store, or any effects the mixture or its elements may have on people, plants or the environment. The information here is for reference only and does not imply a recommendation for use. If you disregard this warning and make any of the preparations, you do so entirely at your own risk.
Joined: 31 Dec 2014 Posts: 1517 Location: West Fermanagh
Posted: Fri Jan 02, 2015 5:49 pm Post subject: Honey Fungus!
Monday (29th Dec) was a lovely day here. I decided to take a stroll around the garden and have a 'poke about' to see what needed doing and how the garden was surviving the winter so far.
I was saddened to see that the box hedge surrounding one bed was showing definite signs of Box Blight, (I thought it might have but was hoping the damage was Tom cat related!)
I then moved into the little wood/orchard that runs down the side of our garden. When we moved in, 16 years ago, there was a dead tree in the wood. We removed as much as possible, but I have experience of honey fungus from my previous garden. As a result I check the trees every year. I have already lost one that was growing close to the dead tree.
The bad news is one apple is riddled with it, as are 3 privet and a hawthorn. Three other apples and a Scot's Pine are also showing signs.
Having totally depressed myself, I was wondering if I can help protect the remaining trees with generous doses of Armillatox? I know, thanks to the EU, it is now sold as a patio cleaner. But the clue is in the name - Armillatox - toxic to Armillaria! It is very expensive and my worry is that just like creosote and Jeyes Fluid it no longer packs the punch that it did. Will I be wasting my money, or should I just resign myself to the inevitable?
An old gardener, when asked the question 'my garden has Honey Fungus, what should I do?' responded 'move house!' I really hope it doesn't come to that.
I would be very grateful for any ideas or solutions you might have.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You can attach files in this forum You can download files in this forum