Pine tree killer

[rogb]

Wonder if anyone can help with a depressing tree problem? The foliage on a few old pine trees (both the umbrella and Aleppo types) on our land has gone brown over the last few months. Some others are showing signs of going the same way, with brown needles near the top of the trees. We had a tree surgeon round today who says we have an infestation of 'ylessine' larvae - which is becoming common in the region and for which there is no viable cure. He says the only thing to do is to fell the trees as quickly as possible. This is not the processionary caterpillar pest, which apparently rarely kills mature trees. We can't find anything about this on the net, even with spelling variations, and we would be grateful for any assistance.

[Roger O]

Possibly European pine sawflies??
(I'm not really sure of this ID!!)
Here are some google pictures to followup (if you recognise "yours") via the links:
http://www.google.co.uk/images?um=1&hl= ... =&gs_rfai=

[rogb]

Thanks but I don't think it's these sawflies. Our larvae are apparently boring their way into the trunk and branches and cutting off the supply of sap from the inside. Once the tree is 'dry' and dead or dying, the moths then emerge and take over new trees.

[thumbelina]

A friend of mine is a forester, RogB. He confirms what your tree surgeon said.

In fact it is "grand hylésine des pins" or, in English "Common pine shoot beetle".

Here are a few articles about the disease.

http://imfc.cfl.scf.rncan.gc.ca/insecte ... ID=1000093

http://www.mnr.gov.on.ca/fr/Business/Fo ... 73970.html

http://www.ofme.org/documents/Sante/bilanMEDIT07-1.pdf

Hope this helps.

[rogb]

It does help - many thanks Thumbelina. We'd just about concluded the cause was either the common pine shoot beetle or its sibling 'tomicus destruens'. We'll be getting in more advice on this and will have to start felling soon.

It's quite staggering how quickly these tiny things can take over and kill magnificent trees, some huge and a hundred or more years old. It also seems that the rain shortfall in the PO over the last few years is an indirect cause of the problem, because the beetles tend to successfully attack stressed or weakened trees. So, sadly, expect to see more dying pines around the region.

[thumbelina]

It is very sad, isn't it?

There is a disease around now which is killing the plane trees too (can't remember the name off of the top of my head) and so a lot of those could end being felled.