Severe cypress die back!

[Danavan]

Dose that suffocate the little blighters? Have used that method on some of my bonsai trees in the past to rid them of aphids.

 

Cheaper too

[Langur]

I've Just arrived at an annual hedge cutting job to see this. I've trimmed them every year for the last 8yrs.

Last year there was minor evidence of drought stress and the previous two years I saw some aphid damage.

I'm amazed at this and can't see an obvious reason but I've got a suspicion.

 

Has anyone else encountered this?

 

I could be wrong but it looks like Cypress canker ( Seiridium cardinale) to me.

Most of the Thuja hedges around here looks like the one in your pics.

Very rare now to see someone planting them . Maybe that's the reason why the disease now is spreading more and more on Leylands.

A big problem.

Did you notice any resin emission?

 

Great forum by the way!

Edited September 5, 2012 by Langur

[treeseer]

Langur is right; check for sticky droplets on branches.

 

Also yes could be Plant Amnest speaks out against Shear Madness!

 

there is more than one way to deal with it naturally, besides not being so tight on the clip. That is to make thinning cuts as well, every 2nd or 3rd shear at least. Yes more time and therefore money, but essential for healthy plants.

 

Because shearing is non-selective heading, you will stimulate bushy regrowth. You create a twiggy outer shell on sheared plants. This layer of twigs shades out the interior, which then becomes leafless and full of dead leaves and dead wood. Meanwhile the outer shell becomes thicker and larger every year because, as it is sheared repeatedly, it must be cut a little farther out to retain its greenery. This dense, twiggy outer shell makes size reduction difficult because cutting back too far exposes that ugly dead zone inside the shrub.

 

It is also physically difficult to cut through the thick twiggy mass. Although most plants will eventually green back up when they are pruned back into the dead zone, but as you now know, the needled evergreens, such as junipers, won't. Therefore, shearing is not a good way to control the size of a shrub. Selective pruning utilizing the thinning cut ensures that there will be a green twig or branch to cut back to and can therefore be employed to reduce a shrub's size while retaining its natural look.

Edited September 6, 2012 by treeseer

[AA Teccie (Paul)]

Morning all,

 

Interestingly Bartlett's showed various P&Ds under a digital microscope at conference yesterday, fascinating stuff I have to say, inc. this. The outcome was a combination of factors, both biotic and abiotic, but often combined aphid, mites and seridium. So no single causitive agent.

 

They advocated treatment with a contact insecticide, under licence, and also considering 'good husbandry' things like soil decompaction and mulching.

 

If anyone's interested they do now offer a 'P&D' diagnosis service AND as part of the report they advise on suitable treatments.

 

Cheers..

Paul