Ash dieback

[Mark Wileman]

1 hour ago, openspaceman said:

The reason for retaining ash trees seems to be in order to establish some sort of resistant genetic strains, I would say if you can see it's chalara (as opposed to other)induced dieback then there's no resistance worth keeping As ash is relatively perishable it's best cropped soonest.  Detieration of ash has been mentioned in threads today by GaryP and @Alycidon

As the infection is annual, chalara needs healthy trees to infect is my understanding? Therefore if it gets so bad that trees get so bad that they wont come into leaf then all it takes is those mature tree with a root stock large enough to survive one or two years of having no canopy? Does that then mean that even of all ash gets hit then by default larger trees will survive?

[gary112]

I like the idea of a government scheme for replanting hedgerow trees but dont suppose it will happen

[Hank]

Are there any preventative measures that can be taken?

[openspaceman]

4 hours ago, Mark Wileman said:

As the infection is annual, chalara needs healthy trees to infect is my understanding? Therefore if it gets so bad that trees get so bad that they wont come into leaf then all it takes is those mature tree with a root stock large enough to survive one or two years of having no canopy? Does that then mean that even of all ash gets hit then by default larger trees will survive?

This is the first I've read of that suggestion. With elms it is true that the disease was restricted to the current annual ring  but I see nothing to think the same with chalara.  From what I have seen the necrotic tissue is quickly colonised by secondary diseases.

[oldgustav]

Planted 4,000 ash whips in 2007 to 2010 as part of a new native species woodland in west Wales. Up until 2015 they were doing well. Now 3,950 are dead or seriously unwell. It's very depressing

[Mark Wileman]

59 minutes ago, openspaceman said:

This is the first I've read of that suggestion. With elms it is true that the disease was restricted to the current annual ring  but I see nothing to think the same with chalara.  From what I have seen the necrotic tissue is quickly colonised by secondary diseases.

Yeah that wasn't meant as a theory of how to tackle it, my knowledge is limited to writing a short report the life cycle of Chalara during my level 3 diploma ?

[headgroundsman]

In a small woodland, 750 trees with a mix of 12 different species, I have included a few ash. Maybe they will survive maybe they wont but worst case will be a bit of natural thinning.    

[Gary Prentice]

I seem to remember that reports from Scandinavia were that large infected trees were surviving for 5-10 years. I suspect that the spores are so endemic that any new growth that may sprout from leafless trees will just get re-infected the same year. 

[devon TWiG]

10 hours ago, Woodworks said:

Not widespread here (West Devon) but few are showing early signs. Only completely dead ash trees are some whips we planted on our hedges and still not positive as to cause of death of those. 

Look at the trees in the verges on the A30 from Exeter to Okehampton , lots of it ...

[Mark Wileman]

1 hour ago, Gary Prentice said:

I seem to remember that reports from Scandinavia were that large infected trees were surviving for 5-10 years. I suspect that the spores are so endemic that any new growth that may sprout from leafless trees will just get re-infected the same year. 

Ah, I thought entry was through the leaves only, not the new stalks. Pretty much they have no hope then. I wonder if Elm will come back one day or will the cycle of young trees getting reinfected be infinite...