What do we have here???

[jefflovstrom]

Euc's are pretty hardy and drought resistant once established. If your seeing gallery's in pieces of dead wood there is a good chance they have one of the two types of longhorn beetles that are doing so much damage. I don't remember their exact time table of life cyclesbut while in the pupa stage they live under the bark damaging the phloem, during anther cycle they bore deep into the wood. Lots of times their holes are hidden from view because of the way Euc's bark grows. Look for places where there is some discoloring or darkening of the bark.
Everything in that area looks stressed. Longhorn euc beetles can smell a stressed tree, and in drought conditions like were having the younger less established trees really take a beating from every kind of pest. the dead ones still are full of leaves, so they went fast, The longhorn beetles can live several life cycles in a tree befor it dies, but lots of times the tree will show little decline, but then go all at once. I
Im betting it's the longhorn beetle. Some areas are really hot zones I love Euc's. For a while we were losing a lot of Euc's in LA and San bernadino,Riverside area. There was a program where they released a predatory wasp and natural enemy of the beetle. It worked really well for a while, then we started loosing euc's again, They discovered a subspecies of longhorn beetle(a little smaller then the other beetle)That wasn't effected by the beetle larva loving wasp Now were back to square one. I would rule out any fungous because it looks like a pretty dry area.
Keep us posted, I love detective work. I see a dead tree somewhere and I'll investigate it to find the cause. It'll enlighten and entertain you. Don't be hating on Euc's. Most the time their problems are cause by mismanagement. Good luck in your quest. Beastmaster

You said it, Beast.
Damned if you do, damned if you don't.
Depending on who you are working for, they love to attack the guy with a cert.

He who control's the water, control's

 

[jefflovstrom]

So, you guy's do what you do.
Jeff :msp_smile:

 

[newsawtooth]

Just for contrast, I had to look at a couple of euc's that the Board were concerned about. Seem's to them like alot of sap running out of the tree's and making a mess of syrup at the base. They were in a landscaped area and got water every day. So much uptake ain't no borer gonna go near it.
Jeff

Yoda Jeff, in an area with a large beetle infestation will vigorous euc's be attacked and repel attacks with sap? Are those Blue Gum's in FTA's picture?

FTA, so you suspect they are in the larval stage? Only way to check for beetles in the larval stage here, is to expose the cambium with a hatchet. It works for thick barked alpine trees, (a pondo, doug fir, or lodge pole can withstand few a trunk wounds to check for beetles) not sure about your neck of the woods though.

 

[beastmaster]

The only real defense against beetle attack(that I am aware of) in a hot zone is to keep the trees vigorous, the occasional deep watering in drought situation, doing no cutting or pruning on them, except for a few months in winter.(assuming we have one).
A healthy happy Euc is less likely to attract beetles and more likely to be able to fight off an attack. Some species of Euc's are more resistant. Iron bark and lemon Euc's are two that come to mind.
I am sure some PhD horticulturalist at some University is right now looking for a Predator to control this subspecies of beetle. I read where their using recordings of beetle communications, and playing them back to the beetles causing them to go crazy, killing each other in beetle riots. One researcher said it was so vicious he couldn't watch.(This was pine bark beetles) Beastmaster

 

[sgreanbeans]

What are all the little white spots on the leaves?
Also, you SoCal guys, what was the name of the other Euc, real dark, nasty sap, looks like blood. I believe it was called an Iron Bark or Iron Side, something like that. First time pruning one, had some of that sap get on my leg, and later that day I tore my pants right where the sap was. When I came home that night. I walked in the door with a limp, holding that spot, my wife looks at me and I say in a stressed voice " cut with saw, call ambulance" She FREAKED!, then she freaked again, on me, when I told her I was kidding and that was not so funny!

 

[jefflovstrom]

What are all the little white spots on the leaves?
Also, you SoCal guys, what was the name of the other Euc, real dark, nasty sap, looks like blood. I believe it was called an Iron Bark or Iron Side, something like that. First time pruning one, had some of that sap get on my leg, and later that day I tore my pants right where the sap was. When I came home that night. I walked in the door with a limp, holding that spot, my wife looks at me and I say in a stressed voice " cut with saw, call ambulance" She FREAKED!, then she freaked again, on me, when I told her I was kidding and that was not so funny!

Spots from the psyllid. Yup, Red Iron Bark (eucalyptus sideroxylon).
Jeff

 

[ForTheArborist]

Yoda Jeff, in an area with a large beetle infestation will vigorous euc's be attacked and repel attacks with sap? Are those Blue Gum's in FTA's picture?

FTA, so you suspect they are in the larval stage? Only way to check for beetles in the larval stage here, is to expose the cambium with a hatchet. It works for thick barked alpine trees, (a pondo, doug fir, or lodge pole can withstand few a trunk wounds to check for beetles) not sure about your neck of the woods though.

I'm not sure that hacking off a piece of the bark on a Euc tree wouldn't be bad given all of the circumstances surrounding the species and environment, it probably would be more significant of a wound here. Those trees up there have far better soils and water supply, plus they just aren't crazy desert Eucs. Unless I hear from anyone with experience, I'm just going to count that method as damage to the HO's property. I can't risk it.

 

[ForTheArborist]

The only real defense against beetle attack(that I am aware of) in a hot zone is to keep the trees vigorous, the occasional deep watering in drought situation, doing no cutting or pruning on them, except for a few months in winter.(assuming we have one).
A healthy happy Euc is less likely to attract beetles and more likely to be able to fight off an attack. Some species of Euc's are more resistant. Iron bark and lemon Euc's are two that come to mind.
I am sure some PhD horticulturalist at some University is right now looking for a Predator to control this subspecies of beetle. I read where their using recordings of beetle communications, and playing them back to the beetles causing them to go crazy, killing each other in beetle riots. One researcher said it was so vicious he couldn't watch.(This was pine bark beetles) Beastmaster

I'm really skeptical about fighting off an infestation that has already happened, but I don't doubt the prevention of one.

That's really interesting fact about overriding the beetles' communication faculties.

What do you think about that Euc's canopy in the pic? It looks very unhealthy doesn't it? Longhorns???

 

[beastmaster]

The canopy does look sparse. Ruling out some kind of root problems,and the fact the beetles are active in that area, I would bet the farm its the longhorn beetle. Prevention is key, but I see Euc's all the time that have fought off an attack,or one healthy Euc when all the others have gone to that big forest in the sky.Euc's have natural defences, but if their already stressed they don't have the ability to defend them selfs, same with most trees. I heard that down under longhorn beetles rarely kill their hosts. Beastmaster

 

[ForTheArborist]

The canopy does look sparse. Ruling out some kind of root problems,and the fact the beetles are active in that area, I would bet the farm its the longhorn beetle. Prevention is key, but I see Euc's all the time that have fought off an attack,or one healthy Euc when all the others have gone to that big forest in the sky.Euc's have natural defences, but if their already stressed they don't have the ability to defend them selfs, same with most trees. I heard that down under longhorn beetles rarely kill their hosts. Beastmaster

Hmmmm, interesting. There are two medium/big Eucs on the property as well. They show some old holes in the bark that have stretched over time. They aren't deep, and they are closed. Not sure if that's beetles or a myriad of other things such as the resident children. It it were beetles, the tree seems to have gotten over them. Their canopies are not robust right now, but I can't say there are any definite signs of deprivations up there.

Well, I found a blue beetle on a log today. It had a shiny, metalic quality to it's color. Know anything about these ones???

One of the guys saw a black looking beetle running wildly. He couldn't describe more about it. It was running around too fast.

 

[jefflovstrom]

Hmmmm, interesting.
Well, I found a blue beetle on a log today. It had a shiny, metalic quality to it's color. Know anything about these ?

Yup, they are really cool!!!, When I was younger, we would catch them and get mom's spool of thread and tie the end to one of it's leg's. Throw them up in the air and call them 'helicopter beetle's. You decide how much thread to let out! Fun times.
Jeff :smile2: