We have around 10 mature White Oak trees in our yard and in the surrounding forest/area. The largest one is perhaps a hundred feet from my back door, it died 2 years ago. Another one a few hundred feet away from it died around the same time. Within the past week we’ve noticed brown leaves falling from a third one along our driveway and I’m certain it’s the same story. I do not want any more of these to die if I can help it.
The largest one was around 11’ in circumference, it was a big tree. Per this site it was likely in excess of 200 years old: Tree Age Calculator - How Old Is a Tree?
The one which appears to be dying now, is ~130 years old. So again, I do not want any more of these to die if I can help it.
Could it be Phytophthora ramorum or is that still primarily only present in California? In the pic below you can see “sawdust” around the base. Is that from a pest of opportunity, borers attacking a weakened tree? Or are they likely the cause of the weakness and eventual death? Any other thoughts on what the ailment could be or ways I can determine that? Any and all help or suggestions welcomed!
I’ve lost 3 in the last 4 years…one probably 30 inches diameter and 25 foot log…but a windstorm got it. As had the other two a couple years previously.
Had about 6 trees big enough to take for logs…they wanted to cut 35 years ago…I had timber cut but not my white oaks I said. Other oak species and hickory I had cut.
There sure are lots of dead large ash trees in these parts. Reminds of the old chestnut logs laying in the woods in my youth. Or the elms that died in the 70’s.
Could be carpenter ants creating the sawdust, but I cannot tell.
130 or more years is likely to have some rot in it some…and ants do exploit those situations.
There’s not enough information here to make a definite diagnoses of the declining white oaks. Research oak wilt. Contact a local state forester or extension for further help.
I think you will find it is ambrosia beetles. This is how it was explained to me by a local arborist.
When oaks are stressed or sick they send out a pheromone to signal to other oaks. Unfortunately the beetles key in on this and infest the trees. They infect the cambium with a fungus that they actually feed on. Unfortunately it is difficult if not impossible to treat and once infected the trees will almost definitely die. The saw dust on the bark is definitely a sign of them here.
I lost one tree (of 3) to this in my back yard and my neighbors on both sides lost all of theirs. Now I make sure to water the trees with a hose just trickling out during dry times, keep a wide mulch ring around the trees and also fertilize, all to try to keep them healthy and keep the beetles from attacking them.
About 5 years ago we had a really dry summer that stressed a lot of oaks and you would see trees all around the neighborhood that had turned brown and dead by late august that year, all from the beetles infecting them with the fungus.
Hopefully I’m wrong and what you have is easier to deal with, but that is the issue taking out oaks every year around here.
I’ve never seen an Ambrosia Beetle as far as I’m aware. When they infest a tree like this are they typically plentiful and visible, or not so much?
Before the first tree was gone I contacted our county extension agent and he said it sounded like some kind of borer. Yeah, “sawdust”, I get it… But that really only became apparent when the tree was almost dead. So I wasn’t sure whether it directly contributed to the tree’s demise, or was just some kind of insect feeding on the tree after it was already on it’s way out from some other malady.
Thanks for the links and suggestions everyone, I have some reading to do.
Oh and while on the subject of big White Oaks, here’s one on my wife’s multi-generational family farm. Based on diameter it’s probably close to 300 years old. Her grandmother born in 1884 said it was a very large tree as far back as she could remember, I don’t doubt that a bit, it’s a monster. That farm is about ~40mi from where we live and I’ve not heard of any dying around there… And would sure like to make sure this one lives on.
Ash are pretty much gone around here now. On that same family farm was the largest one I’d ever seen, just under 15’ in circumference. That likely puts it at well over 200yrs old. Before it succumbed, I actually tried a basal spray of Imidacloprid with pentra-bark surfactant. Too little, too late unfortunately…
Basically no Ash or Elm or Butternut around here, few Hemlock, Chestnut long gone… Shame.
We have several red oaks dying in our neighborhood my neighbor has one no sign of borers. Their yards are heavily treated I sometimes wonder if that can over time kill trees.
My friend is traveling in a vehicle but is an accredited oaks author among various PH D’s etc. He says, " It does look like phytopthora, but not ramorum. Tell him to Google phytopthora / white oak / Missouri and get more info."
A humongous butternut succumbed near Cumberland Gap…(Middlesboro)…I was given 4 unripe nuts in July…I’ll stratify and plant…but probably they are too immature.
I do have 3 chestnut seedlings in pots. And know of a few nut bearing ones in the wild…but they are very rare.
There were 3 rootstocks from the bundles I got from CopenHaven farms this spring that had AMBROSIA BEETLE frass/sawdust…but I cut the stems and sent to the landfill…rather than cut them open looking for the actual beetle.
Been 18 years since I saw my first ‘wooly adelgid’ on hemlocks in North Carolina.
They are here now, but I’ve yet to see one on any hemlock tree not in the Daniel Boone National forest here in Kentucky.
Thanks for checking with someone with such specific knowledge and experience.
A quick search of those phrases returns this example article. Abstract from it:
Widespread decline and mortality of white oaks (Quercus alba ) occurred in Missouri Ozark forests between 2011 and 2017. Symptoms included rapid crown death with bronzing of leaves, retention of dead leaves, crown dieback and thinning, and loss of large limbs within one year of death. Decline and mortality were associated with hillside drainages and fit descriptions of European oak forests predisposed to decline by pathogenic Phytophthora species. A survey was performed at two locations in 2014 and 2015 to assess the distribution of dead and declining white oaks, and the occurrence and distribution of Phytophthora species. Multiple Phytophthora species were detected, including P. cinnamomi , P. cactorum , P. europaea , and P. pini . P. cinnamomi was the most common and widely distributed species among plots at both locations. The detection of P. cinnamomi at the base of white oaks was not associated with poor crown vigor. However, more quantitative survey techniques are necessary to clearly evaluate this relationship. P. cinnamomi kills fine roots of white and red oaks in North America and has been associated with the decline of white oaks in the United States (Ohio) and other countries. Further studies are needed to determine the importance of P. cinnamomi in oak decline within the Ozark highlands.
The described rapid crown death, bronzing of leaves, retention of dead leaves, etc… That is pretty spot on to what I’ve witnessed so far.
If it is a species of Phytophthora to blame, I’ll concentrate on how to fight/kill it. Still need to read further on it but at present, I’m not 100% certain how it would be classified. Is it a fungus? a bacteria? a virus? This sure doesn’t do a lot to clarify that(!):
Phytophthora sp. is a genus in the oomycetes, which are similar to filamentous fungi in morphology and habitat, but phylogenetically more closely related to brown algae and diatoms and fall in the kingdom Stramenopila. In the past few years, several viruses have been characterized in Phytophthora species, including four viruses from Phytophthora infestans, the late blight pathogen, and an endornavirus from an unnamed Phytophthora species from Douglas fir. Studies on Phytophthora viruses have revealed several interesting systems. Phytophthora infestans RNA virus 1 (PiRV-1) and PiRV-2 are likely the first members of two new virus families; studies on PiRV-3 support the establishment of a new virus genus that is not affiliated with established virus families; PiRV-4 is a member of Narnaviridae , most likely in the genus Narnavirus ; and Phytophthora endornavirus 1 (PEV1) was the first nonplant endornavirus at the time of reporting. Viral capsids have not been found in any of the above-mentioned viruses. PiRV-1 demonstrated a unique genome organization that requires further examination, and PiRV-2 may have played a role in late blight resurgence in 1980s–1990s.
There’s a mature Butternut near the pretty much former town of Clinchport in southwest Virginia. An uncle spotted it and has gathered nuts from it for quite a few years. He has some growing at his home now and gave me a seedling late last year, it’s growing well. They’re certainly not something I see often around here. He and my father talk about how many trees there were in their youth. I’ve discussed on other threads on this site how they remember them being so thin-shelled as to be crack-able via their teeth. I’ve not found any literature talking about that, nor anyone on here so far having ever heard of it. So I have to wonder if it is (was?) a cultivar unique to the region where they lived. They talk about playing in the woods, getting hungry, climbing barefoot up into a large butternut tree and eating their fill. They were quite poor, they certainly weren’t carrying a hammer or a nut cracker with them… Love to have a tree like that!
I have only a small seedling Chinese Chestnut growing so far. Wish they’d just go ahead and release the Darling 58 or a successor with the blight resistance edited into it’s genes. Would love to see the American Chestnut revived and flourishing again.
It was probably the early 2000’s when I first saw HWA infested Hemlocks as well. I and my wife took a drive through some national forest areas in TN and NC today and there were a lot of them standing dead. Shame… The same uncle I mentioned above owns a few hundred acres bordered by national forest in southwest Virginia. The forest service released some kind of natural predator beetles a few years back and they made their way onto his property. He says there is far less to no evidence of HWA “cotton tufts” on the underside of limbs now. Hopefully that happens in plenty of other areas… And hopefully those beetles don’t turn out to be bad in some way nobody anticipated
I wonder if I’ve seen Ambrosia Beetles and around here and just failed to properly ID them, hmm…
There’s several borers of oaks. I don’t know them right off personally… but I mis-identified one of them here on a grafted cultivar I named. You gotta measure the hole and the shape(s), (of course.)
Here in my part of Virginia, it’s the Red Oaks. Where I lived previously I was on maybe an eighth of a wooded acre, and had at least 7 mature oaks die. It was happening all over the county. The arborist that came to remove them said it is happening up in the national park as well.
Why aren’t you sending a sample to a plant pathologist at the land grant university in your state for specific diagnosis? Have you contacted your county cooperative extension?
I’ll assume you are suggesting that that be done as opposed to asking why I’m not smart enough to know to do so I will certainly look into what resources the Univ of TN might offer in that respect.
And yeah, mentioned earlier:
That plus he advised that if greater then 1/3 of the crown is brown, it will likely die. Yeah, it did… But still not convinced the borers were the cause of that demise, really wondering about a Phytophthora being the culprit. Hopefully it can be pinpointed and a larger die-off can be circumvented…
Thanks. Did so and it seems like “Phosphite” is mentioned a number of times. Sounds like it and/or other fungicides struggle to totally kill the pathogen, but can beat it back to the point a tree can overcome.
Oh and it does seem like Phytophthora is a genus of fungus with numerous species. The article I found mentioning viruses threw me off… Seems like they are talking about viral infections of the fungus itself. Great, a multi-front attack…
