root damage on young Ash plants

[Stumped2010]

As my log in name says...I'm stumped! I have 3 year old ash plants which have died. I can see evidence of below ground feeding and there are semicircular cracks on the above ground part of the stem (though I don't know if those are directly caused by insects, or if they are just the tree dying uot as it has root damage). I've attached a photo of the damage, but I apologise for the quality as it has been taken using my phone.
Any suggestions as to what might be causing this type of damage would be greatly appreaciated.
Thanks

[Cotham Marble]

Originally Posted by Stumped2010

As my log in name says...I'm stumped! I have 3 year old ash plants which have died. I can see evidence of below ground feeding and there are semicircular cracks on the above ground part of the stem (though I don't know if those are directly caused by insects, or if they are just the tree dying uot as it has root damage). I've attached a photo of the damage, but I apologise for the quality as it has been taken using my phone.
Any suggestions as to what might be causing this type of damage would be greatly appreaciated.

Welcome to WAB.

The picture doesn't really allow much in the way of diagnosis but .... it appears there is a lack of fibrous roots, if that is the case then an obvious culprit would be Vine Weevil grubs. Were these plants being pot grown ? if so Vine Weevil is a likely candidate.

CM

[Stumped2010]

Thanks CM. I cracked the roots open to see if there were any tunnelling larvae, as I would have thought their should be for Vine Weevil, but there were none. The feeding on the main root seems superficial, rather than something boring into the root. There is certainly is a lack of fibrous roots though. Plant were not pot grown as, if they had survivied, the plan was they would form a woodland.

[Cotham Marble]

Originally Posted by Stumped2010

Thanks CM. I cracked the roots open to see if there were any tunnelling larvae, as I would have thought their should be for Vine Weevil, but there were none. The feeding on the main root seems superficial, rather than something boring into the root. There is certainly is a lack of fibrous roots though. Plant were not pot grown as, if they had survivied, the plan was they would form a woodland.

Vine Weevil larvae tend to 'graze' on the tender fine roots, rather than 'burrow' and are usually found in the surrounding soil, and once the available roots have been consummed will move away in search of a new source. I wouldn't rule out Vine Weevil but as your plants were grown in open soil then perhaps one of the Chafer beetles (larvae are very similar to Vine Weevil) are responsible. The Chafers mostly feed on grass roots but may on occasion attack the roots of saplings. Did you by any chance plant into an area of old lawn ? More on Chafers here: Data Sheet - Chafer Grubs : Buzz Organics, Biological pest controls, green pest controls, organic pest control

I'm sure someone else will be along with other suggestions.

CM

[Stumped2010]

The habitat shound about right for chafers as the ash were planted in a pasture. Thanks for the info and links. I'll have a dig around and see if I can locate any larvae.

[The Woodman]

I'm struggling to make the damage out in your image but could it be voles?

They do kill young trees by ring barking at or just below ground level - but it depends on how far below ground level of course.

I've found a picture of roots damaged by subterranean feeding here
http://www.google.co.uk/imgres?imgur...26tbs%3Disch:1