Protecting trees from squirrel debarking

I planted a native bur oak in my yard in Missoula 15 years ago. It is now 20 feet high. A beautiful elegant tree.
Right after that bad cold spell we had, I suddenly noticed that the upper half of the tree appeared orange.
Imagine my horror when I looked more closely and realized that all the bark was peeled off the upper half of the tree (trunk & branches).
I contacted the city forester, and he confirmed my fear that squirrels likely chewed all the bark off.
And probably deep enough to kill the entire upper half of the tree.
I had never heard of this happening to a tree, especially after it was this size.
I asked if there was anything I could have done to protect the tree, and the forester said, probably not.
Squirrels can get around just about any physical barrier, by jumping from nearby trees.
and if I tried to protect the tree now, I'd have to remove all the lower branches to keep squirrels from jumping up on them
to get around the barrier and then the tree would have nothing to live on.

So I wanted to ask if anyone knows of some sort of repellant that could be put on a tree to keep squirrels off the tree?
I hate to keep squirrels off an oak, but if they are stupid enough to kill a key food tree for themselves,
I think I'm doing them a favor to keep them off the tree. Then they could pick up acorns off the ground.

Hi Vicki welcome to the Permies forum,
I did a little internet research and discovered that the debarking had apparently been studied on american gray squirrels in the UK. They concluded that the squirrels may have developed a habit for debarking because after they removed a certain number of one species they moved on to other species.

When I read this the one thing I thought of the saying (can't remember where it is from) "everything gardens". My analysis would be that the squirrels may have some reason for taking out the tree, or perhaps they are being foolish animals and destroying they're food source I am not sure.

If you are intent on keeping them off the trees the one thing I could think of would be a Sepp Holzer bone sauce, that appears to keep large mammals away but I wouldn't be surprised if that effect extended to all mammals in general would not want to taste the bone sauce. (If it does work it will work for a long time with a singe application as well)

Anyhow I hope I was somewhat helpful and good luck.

Daniel

Thanks, Daniel -- it does seem very foolish of the squirrels to attack an oak that had just started making acorns, when the only other trees on our street are maples. Also strange that they waited until the tree was 20 feet tall and many years old. Guess it was a hard year for them.
Or perhaps the squirrels got into meth or something.

Anyway, thanks for suggestion about bone sauce. I found info on making bone sauce -- quite a process to make it.
Perhaps making it and selling it could be come an enterprise for someone.

Anybody out there making bone sauce?

Ya I personally have 0 experience making bone sauce, it seems like there is a certain temperature you are trying to maintain over time, but if you research and think about it long enough you can probably pull it off.

Here is the sepp video explanation if you did not find it yourself.



This was my only idea, squirrels are so tricky I feel like you cant really fence them out, if they want to kill the tree then short of patrolling the tree with a .22 I don't know if you can stop them.

Maybe someone else has some better ideas.

One thing is, if you know it is going to die cut it down while the wood is still fresh and driable and make some tiber etc.

I wonder if anyone else has experienced this phenomena? As I have not had experience with it.

@vicki

We have a major problem with squirrels in our forest (oak, hickory, walnut, persimmon, cherry). We have seen some stripping; however, our bigger issue is they raid all of the fruit and nuts. We do not have a proven solution. We plan to try nailing rat traps to a few rows of trees to push them to the deeper areas and outer edges. In your case, with only one tree to protect; it could work quite well. If you hear the snap; you could remove them immediately for processing, if they are to your taste.

I am guessing that the squirrels food sources are scarce . You say the street you live on has mostly maples which do not provide squirrels much in sustenance . Are you living in an urban area ? If so , what is providing the food stock for that population of squirrels . In most urban areas it is song bird feeders . If this is the case talk to your neighbors about putting out suet in the winter as opposed to seed . I live in the country , we have squirrels galore . Also black walnuts . If the squirrels are eating walnuts it means the hickory and oak mast is scarce . To have squirrels eating bark sounds like famine conditions for those buggers . If you are not in the city and it is permitted perhaps a good squirrel hunt is in order . Get a few for stew before the famine gets them first.

@WAYNE...

We are in a somewhat suburban area out in the country. (Private roads with small neigborhoods of 10 - 50 homes, each on 10-40 acres, a few 60-100 acres). In our area it is heavily forested; filled with food sources. We have an abundance of many types of native and migratory animal and fowl. Our predatory balance is very off. Those we have, have learned to hunt the captive livestock, fowl, and pets...they can be very easy pickings. Squirrels and rabbits take work. And, while squirrel is a Virginia food source for humans; most people in our immediate area and township do not eat them; even our deer population is not kept in check, due to lack of on property hunting in our immediate area (legal, just not done). We are surrounded with families who are either city minded or urbanites enjoying the nature. Most have no concept of land management of any kind. We do need to cull the population; they are over abundant, despite there being rich food sources. My Grma was from Arkansas; she grew up hunting and eating squirrels on their farm. As an adult, she never hunted and fixed them; so, as far as I remember, I have never ate them either. It seems like a lot of work for very little meat. So, I am not sure we will be eating those we kill with the traps. We are planning to burn and compost them currently.

I don't think your forestry agent has a clue! I've never heard of squirrels killing trees, and if you think about it...that statement just doesn't sound right. I would believe you had some variation of the various scales and blights that had widespread affected oaks in this country. You might notice that CA & TX had a devastation of live oaks...which continues to this day. Some say it is water borne disease, but no one has blamed the squirrels, most say there is very little that can be done. It is quite possibly spread from burning firewood, some have claimed that. If indeed it is this scaly blight of some type, if it is blueish grey, that tree will die, within a year. If the scaly is yellowish and powdery, it may live with it for some time. If it is white and powdery it will die soon. The pink coloring type has not killed any of my trees that I know of, but it just showed up last year, and it doesn't seem to invade into or displace the bark, seems to remain on the outside of the bark.

I wish I had a solution for your oak losing its bark, which is normal on the shaggy white oaks, they shed seasonally, even young ones. Post oaks also shed their bark, but not as often as the shaggy variety white oak. The red & black oaks seems to hold onto their bark showing little evidence of shedding...unless there is truly a problem.

james beam

More pixs & descriptions

james beam

A few more pixs from today.

james beam

more pixs...none of these were damaged by squirrels, or woodpeckers...but they might carry these spores of disease from tree to tree. Squirrels and woodpeckers take very good care of the trees, and heck ya they will try to get the first fruits of their labor whenever possible.

I mentioned white, pink, blue, yellow scale or blights, there is also a black that mainly attacks dead wood first.

james beam

@James...

Great pictures and info! Excellent for future ref. In our forest; a few oaks, blk cherry, and hickories have had bark stripped...not, scale nor blight. We were not sure which animal was responsible; however, all trees in question have squirrels frequently. We have wood pecker damage in some other trees; the pattern is quite different. Our goats and alpacas have stripped other lower trees in spots; and, what we are seeing up very high is similar to that damage. If you are correct, and, squirrels do not strip trees...Who is our culprit? If no one knows; our traps once up, may provide the answer in our case.

Squirrels stripped a bunch of our aspens last summer. They also stripped some poplars and other trees. First time I have ever seen this but they did do it. I was perfectly happy to live with them untill I saw them do this. There are a lot less of them now.

Hey Cortland, I only wish I was a biologist or bugologist, it would be my guess, around here at least, the problems serious and widespread, are generally due to bugs/diseases/fungus of various types, not withstanding climate change, and Fukishima type occurrences that are possibly related.

2 years ago for example we endured an extensive drought, then midyear of 2013 we got hit very hard with the oak leaf caterpillar, which literally defoliated every oak tree, luckily there was enough time for the oaks to regenerate new leaves before fall, a 'natural reflex' cause from the drought the previous year...I believe. Stresses of various types affect trees, the resulting clean-up by the bugs, squirrels, & birds is kind of an reaction to what really happened, or is happening. I saw squirrels literally gorging themselves on caterpillars in 2013, I even saw the foxes lapping the caterpillars up from the ground they were so thick. If a tree is infested with bugs, all types of critters will come to eat the bugs, I suppose squirrels will strip bark to get at a beetle.

As far as I can tell this blue scale is absolutely deadly to any tree that gets it, be it mostly affecting red oak, but white oak also, I've not seen it on hickory nor wild cherry, nor maple. The blue scale literally works between the inner surface of the bark and the outer surface of the sapwood, and subsequently the bark falls off...revealing the blueish-grey scale. I have found this scale...which seems to occur when trees are overcrowded...closer than say 10' from each other. This blue scale has been affecting trees around here for at least 10 years, maybe it is a natural thinning mechanism, I don't know the answer, except I try to keep the easy to get to ones cut up and removed.

We have an high number of grey squirrels that live around here, I've seen them rip up and down trees, bark flying...but they are only playing chase and not doing any harm. I probably shouldn't have said "I don't think your forestry agent has a clue!", as I don't have a real answer as to what is causing Vicki's tree to get ate, I was just trying to give some examples of what might be going on with it, and I don't agree that the squirrels are the actual problem. If for example the tree is to the point of bleeding streaks of sap, then you got a problem for sure, but bark shedding is somewhat common on the white oaks, I don't know about the burr oak variety and how it's bark behaves in nature.

james beam

@James and @Miles...

Very interesting happenings in both your forests! James, I will be keeping an eye out for any future spore or bug invasions that could be problematic. Miles, you decreased your over population of squirrels...any suggestions on methodology?

A quick google search for squirrels debarking trees produced numerous images of damaged trees attributed to squirrels eating their bark and numerous articles and other discussions of the activity and the problem it represents.

There did not seem to be very much in the way of solutions being presented, unfortunately. It seems to be a serious enough problem in Taiwan that they are addressing it by replacing trees the squirrels debark with trees the squirrels do not debark. In Britain squirrel damage to forest lands is a substantial issue with very real economic costs. The abstract of the British article mentions solutions to the problem and expenses associated with managing it, but does not indicate what the solutions they are using may be. I expect the full article has more information on just how they are addressing the issue.

Definitely a real problem, with multiple species of squirrel getting in on the act and occurring globally.

Here are some pictures of my young oak tree that I think was debarked by squirrels. It is around 15 years old and at least 15 feet tall.

bur oak debarked missoula Vicki

Its been a tough winter this year for the tree rats squirrels here in Montana. Deep snow and cold make it hard for them to find their normal foods, and they will make do with bark. Actually they debark to get to the live/dormant cambium underneath. I don't think the bone sauce will work if the name is the true source. Squirrels will take bones from animal kills to gnaw them for the calcium, and antlers of deer or elk are favorites for them. Sepp says that mice don't mess with it, so it is a possibility that squirrels will find it nasty as well.
Biggest thing, try the bone sauce and see if it works. Can't be popping them with a .22 in the city limits of Missoula to thin the population, although my pups do love squirrelcicle and are know to run up the side of the old cottonwood and snatch them off the side of the tree.
Looks like that bone sauce would be a good means to keep all kinds of gnawing, bark loving critters away from your juvenile trees and give them a chance to grow, especially since mice, rats and rabbits are famous for burrowing under the snow and girdling young trees.