Bulb Log 2019

[Ian Y]

Happy New Year everyone, I am back with another year of Bulb Logs and there is no shortage of work  or flowers this week.


http://www.srgc.org.uk/logs/logdir/2019Jan021546428317BULB_LOG_0119.pdf

[Steve Garvie]

Happy New Year Ian!
Another entertaining and informative read though I feel somewhat guilty that you are grafting in the garden while I sit in front of a warm fire supping Port. 

I’ve also had die back of a mature Sorbus which was followed by the “unexplained” death of a couple of mature Rhododendrons (augustinii and thomsoni). I fear that Honey Fungus was the culprit. The dead wood supported fungi not unlike the main image you posted though I could find no evidence of the characteristic “bootlace” rhizomorphs. Is it possible that a form of Honey Fungus could be causing the die back issues you have seen?

[Ian Y]

Steve I am very interested to learn your experiences and do know the problem that honey fungus can cause and I did consider it as a possibility but I do not believe that to be the cause in our garden.

There appears to be a number of fungi that can have the common name honey fungus but what is growing on the stumps I show is not The Honey Fungus also all woody plants surrounding are in good health.

I will be keeping a very careful watch on the situation.

[Alan_b]

I lost a mature sorbus unexpectedly a few years ago.  The death was followed by a good crop of mushrooms around the base which certainly resemble the ones in your picture, Ian.  But I am no expert on fungi so it might just be a superficial resemblance.  My crop of mushrooms I took to be Honey Fungus, but I'm no expert, as I said.  Here is a picture I posted at the time http://www.srgc.net/forum/index.php?topic=14346.msg366900#msg366900

[Steve Garvie]

Hi Ian,

I gather there are a number of species of Honey Fungus (Armillaria) which vary in the appearance of their fruiting bodies and in their plant pathogenicity. All have white spores and this can often be seen as a powdery “icing-sugar” coating on the tops of the lowermost mushrooms (falling from the “gills” of those above). I gather that trees are mainly infected by the thick bootlace-like roving rhizomorphs which grow out through the soil from infected plants at a rate of about 1m per year. Spores very rarely cause infection in living plant tissue. The fungus attacks the host plant just below the soil surface invading roots and the root collar. Death occurs when the fungus fully girdles the host.
These fungi thrive on both living and dead wood but the rhizomorphs themselves are only viable when attached to the “main body” of the fungus deriving their nutrition from the decaying host tree. It follows that removing all dead wood and infected woody plants is beneficial as is deep cultivation of the soil (by cutting through the rhizomorphs and depriving them access to their food source). Butyl liners sunk into the soil can act as a physical barrier to spreading rhizomorphs.

There are a number of resources on the internet regarding Honey Fungus -most make grim reading. In reality spread of infection is usually haphazard, slow, creeping and unpredictable but generally without the domesday scenarios predicted in the literature/online. I would certainly remove as much of the infected plants and deadwood as possible -preferably burning it or disposing of it offsite. Digging deep trenches around nearby treasured woody plants might prevent spread of rhizomorphs (which can be incredibly difficult to find) and avoiding mulching with brushwood chippings is probably also sensible as is clearing soil away from around plant collars. Armillaria target woody plants including trees, shrubs and some woody perennials. The appearance and spread of infection is complex being linked to fungal pathogenicity and host susceptibility.

Of course all of this is unnecessary if you do not have Honey Fungus and I think your first step is to obtain a true “diagnosis”. Look for white sheets of fungal tissue between the wood and bark of the infected tree at and just below soil surface level -this has a mushroom-like smell. Check the colour of the spores and look for evidence of rhizomorphs in the ground radiating out from the infected Sorbus. If this is Honey Fungus then I fear you will have some hard graft ahead of you. Conventional wisdom is that there is no chemical treatment for Armillaria infection. In the old days a 1:20 solution of Armillatox poured around the woody base of mildly infected or at risk plants seems to have been effective. Sadly my supply has long gone and I don’t think it is available online these days.

[Maggi Young]

 Yes Steve, there are a number of  "Honey Fungus" types which are in the genus Armillaria - as well as a good number of  honey coloured fungus of innocent mien, which may be tarred with the same brush, while  being harmless.

 I believe the  fungus pictured  by Ian on the cover of  Bulb Log 0119 (shown on  on a dead  cotoneaster trunk) is harmless. Not least because  it has no "collar" on the stem.

[ian mcdonald]

I lost a birch, a plum, a rowan and a rhododendron through fungal infection (honey fungus) and it even grew on the garden shed.

[bibliofloris]

I’m very pleased that the Bulb Log will continue for another year — thank you for all the work you put into it every week, Ian! (And to Lee for the index, too!)

Now I’m waiting for a break in the rain to check the progress of my galanthus and hellebores... In my area, it’s recommended we cut old hellebore leaves now to get rid of any botrytis they might be harboring. Maybe this will be the year I finally get around to putting limestone chips around them too, like I’m supposed to! (Said to keep any botrytis spores from splashing up onto the leaves in our rainy weather.)

[Ian Y]

The Bulb Log where Narcissus continue flowering plus preparing the drive for spring flowering.


http://www.srgc.org.uk/logs/logdir/2019Jan091547033129BULB_LOG_0219.pdf

[Robert]

Ian,

You have tremendous success selecting worthy varieties from a very small number of plants (relative to commercial plant breeding). I hope other gardeners are taking note.    You have demonstrated that even open pollinated plants (Narcissus), and small populations numbers can yield excellent results if one has a keen eye. Worthy new plants must arise in many gardens.

[Ian Y]

Shoots, sprouting seed, flowers, DNA and mulching are among the things to see and read about in this week's Bulb Log.


http://www.srgc.org.uk/logs/logdir/2019Jan161547637640BULB_LOG_0319.pdf

[Robert]

Hi Ian,

You mentioned Sudden Stratospheric Warming (SSW) in your latest Bulb Log. Are you experiencing a minor, major, or final event? I have been observing high amplitude Rossby Waves over the eastern Pacific Ocean / western U.S. this winter (ridge/tough pattern on a continental scale). Are they of the “type”, of high enough amplitude to trigger SSW? This is something I do not know. This exaggerated pattern is not unusual, but then minor SSW events generally occur every winter season. I frequently (generally daily) monitor IR time loop planetary circulation patterns. I will pay closer attention to the Polar wind patterns. I missed last winter’s event.    Thanks for mentioning this atmospheric phenomenon. It is certainly pertinent to gardeners in Europe and most likely elsewhere.

I enjoyed another visit to your garden (through the Bulb Log). When I can, I handle winter leaves in the same manner. Lately, I have not had the time to grind the current season’s leaves, but fortunately I have plenty of leaf mold to spread over the areas that I cleared of matted winter leaves. This certainly enhances the survival of germinating seedlings, something I too wish to encourage. In other locations I remove all the leaves. Many of our California native annuals germinate well on mineral soil without organic cover.

 

[Ian Y]

Thank you for all your comments Robert, I am not sure what the severity of the SSW is all I know is what was reported by the official weather folks and the exact consequences have not fully played out yet - I will as always record any extreme weather events in the Bulb Log.

[Robert]

Hi Ian,

As stated, I enjoy visiting your garden through the Bulb Log.

I will be very interested in any extreme WX events. I have my hands full with our mesoscale WX (Sacramento, California to the crest of the Crystal Range - especially the western slope of the Sierra Nevada in El Dorado County, California). Having said that, teleconnection is still very relevant in my world. As I read the Bulb Log, sometimes I need to ask questions for clarity. I know very little about SSW and at some point I will look deeper into the topic. Thank you for answering my question regarding the current status of the SSW.

[Robert]

For those interesting in delving into Sudden Stratospheric Warming there is a good article in the journal Eos, the Journal of the American Geophysical Union, on this topic. It is very easy-to-understand. If I can find a link to the article I will post it here.

Here is a graph that may illustrate the concept of Sudden Stratospheric Warming.