Leylandii aphid damage

Apart from chemicals or digging the whole thing out, what if anything is the best treatment for a stricken Leylandii, whose leaves/needles are all turning brown?

 

Cutting it down.

 

are you sure its aphid damage.

 

Are you sure it`s Leylandii?

 

I mentioned this in a post recently, I have seen lots of this over the last couple of years and none previously definatly on the increase. If it is and it could be lots of other things, depends how bad damage is this cold winter may have stopped the cycle and contary to popular belief brown patches in conifers can slowly green back up. If damage is really usightly and its brown right through, then removal is probably best.
Why do you think its aphid btw?

 

I have only seen the Leylandii once, it belongs to someone I garden for. All the research I have done suggests its aphid damage, but of course we will fully examine it and identify the problem. I just wanted to sound out the possible course(s) of action for the worst case scenario. Plus, I am writing an essay for a course on aphid damage to Leylandii and how to respond to it.

 

If it is the aphid damage that was reported a while back as destroying the much hated laylandii hedge up and down the country then not sure what can be done. There is one in a garden near the South Downs that has been brown and dead for the last two years and they're just left it. There doesn't seem to be any regrowth occuring and it looks dreadful (actually, I think they look dreadful even when they aren't dead).

From what I've read, the aphid starts on the inside of the hedge and eats it's way out, so by the time you notice damage it's too late to do anything about it in most cases...

 

I can eventually recover as the damaged area grows-in but it will take years to do so. In severe attacks the hedge may be so disfigured that removal and replacement may be the favoured option. How bad is it?

 

Okay - thanks for all your input. For anyone who is interested, here is the latest:

I told the old couple what our options were, and they wanted me to cut out all branches with affected needles/leaves, which effectively resulted in a whole chunk of the hedge being removed. There was further aphid damage along the other half of the hedge but they wanted me to leave that half standing for now. This old couple are nobody's fools, and certainly know their garden, but I was slightly concerned that leaving the remaining hedge, with its patches of brown damage, would mean the problem eventually got as bad on that side as it had on the other. However, the garden's owners seemed happy to take this risk.

The "gutting" of the hedge also meant that one half of their garden is "see through" which affects their privacy. The gentleman was very keen on the idea of leaving some branches, devoid of pedicels, which means we now have a few skeletal Leylandii trunks with odd bare branches jutting out, full of small stubs where the offending articles were cut off. I did explain that this might cause dieback, but they were determined that we should leave it.

Chris, in the post above, says that the hedge may regrow healthily but that it may take years, so I expect we may have to find something to fill the gap. I would be interested in what people here think - whether we have basically set up a dieback accident waiting to happen, whether the leaves will regrow successfully, or if we will just have to wait and see. Perhaps there are steps to take the ensure the successful regrowth?

 

Mmmmmm. Sounds really attractive. NOT! Still, it's their garden and they have to look at it so if they're ok with it...