Italian Cypress Dead

[btchild]

Two 40 foot tall cypresses in a line of 20 in my back yard have died. On investigation, I observed that the lower branches have on them what looks like sawdust, or even more like termite droppings. It appears that this has fallen from higher up on the trees. The healthy trees do not have this. Is this characteristic of some insect infestation? Should the trees be removed? What protection can I give to the remaining trees?

 

[Ekka]

Looks like a few on the RH side of the pic are dying from the bottom up too.

That sawdust material is called frass. It's a combination of excrement and sawdust and possibly fungas.

I'm no beetle expert but that's what it looks like. Some wasps and moths do the same. An adult lays eggs, the larvae hatch and eat away at the cambium under the bark, ringbarking the tree which kills it. Some species of pests carry a fungus with them so the timber has softened due to decay making it easier for the larvae to eat. They tend to attack the weaker more streesed trees, if they get a good hold they can migrate to the healthy trees. I know it's advised to get rid of the dead ones quick smart.

It's difficult to ID the exact culprit but controlling them is tough. There's a few experts on the site that should jump in and help.

 

[treeseer]

I'm way across the continent, so it's hard to say whether the bugs caused the death or are just feeding on it. You need a local expert on site. www.asca-consultants.org, or www.isa-arbor.com

 

[btchild]

Sure enough, the trees were killed by a root fungus and the bark beetles are secondary.

 

[treeseer]

Sure enough, the trees were killed by a root fungus

What's its name? What's the treatment to prevent spread to the others?

 

[Ekka]

Hey Treeseer

How would one diagnose a root rot fungus and treatment just like that ... from all the stuff I've read it's not that easy and some of the tougher fungi are pretty well impenetrable.

We had a large seesion of conifers suffering similar symptoms back in the mid 90's, they injected some copper based paste but you had to catch the disease early. They also recommended spraying conifers with some copper stuff to help build resistance. It wasn't copper sulphate though ... ???? I can't remember it, we don't have too many conifers here.

But the problem appears to be re-emerging, I've taken a few out this year and as I drive around I see them starting to get brown patches from the bottom up. Mainly in the smaller ornamental conifers like Thujas.

 

[treeseer]

Ekka you're right, it's not easy. I was just following what bt said, looking for specifics to test credibility.

Re your conifers, serach 'redfire", a bacterial disease.