Why did they do this to these trees ?

On a plot of public land I hunt, I found several small trees with the bark cut all the way around and then painted with an aqua green paint. All had a small branch snipped from them like a sample was taken . Who did this and what is the purpose ? -Thanks

Beetle survey?

It appears they were girdled for some reason.

Drought or lack of info.? Sorry, just throwing thoughts out there.

Girdled - Not by beaver most certainly!

I believe the paint is herbicide to kill them. I've seen it done around the last year. It's a government program that pays the land owner money to kill the unwanted trees within a certain distance of trees that have timber value like oak and walnut.

It looks like someone did a "Hack and Squirt" to kill unwanted trees. https://www.youtube.com/watch?v=CGM1VsTQoQg

Tordon can be that blue color. It is used to kill woody plants.

Are they elm?

Hack and squirt, probably timber stand improvement=kill some of the trees to let the remaining do better

All the ones I saw like that were less than 4" diameter and less than 6' tall . Why not just cut them down ?

If you cut them down they can sprout back from the stump.

Hack and squirt is fast. Hatchet in one hand and spray bottle in the other. I prefer just to take the chain saw. Hack and squirt will not work on hickory unless you go deep all the way around. Any gap and it will grow back.

It replicates natural dead standing trees that are important to woodpeckers flying squirrels and bats that like to hide behind the loose bark . I t also dosnt clutter up the ground story as bad as cutting them .It makes for a very haxardous woods in about 3 years as they shed branches every time you bump one it makes driving a tractor in the woods VERY VERY DANGEROUS .
Leaving them Stand also reduces light shock to to species like walnut and hickory that have a tendancy to pin out (grow small limbs on the lower trunk] if the understory is cut completely away. The standing skeletons slowly transition to full sun over a few years
Myself i like cutting them it gives immediate ground cover and bramble growth that supper charges your deer ,rabbit ,and pther small game that prefer brush pver pure open mature forest .

They were girdled with a hatchet or machete and herbicide applied to the cut. The blue color is simply a dye pigment added to the herbicide mixture to be able to easily tell where the herbicide was applied. We use this method regularly to take out unwanted trees/brush that are competing with our pine trees. If it was done on public land timber production is most likely not the management objective. Maybe they are favoring other plant species more favorable to wildlife. It is a very good method to apply herbicide to only the tree that you want to kill verses a broadcast treatment.

Look like locust trees to me.

X2

hack and squirt herbicide treatment. Dye was added to mark which trees were treated.

Invasive species that land management is killing?

Gotta get through bark to kill

That would be your state thinning out chosen species. The recommendation is for trees less than 6 inches in diameter, and not by roots linked up to other trees. We have Buckthorn here which is invasive, wood is hard on chainsaws, and they grow like weeds, so it is sound management using Tordon as it is target specific. It is the quickest, least labor intensive and less noisy method. The State can send college children out to get bit by bugs and it is all part of the life cycle.

Not necessarily invasive species, sometimes just undesirable species. I hunt a 3,500 acre timber company lease in north-central PA. A couple of years before a big sale and cut on a section they come in and remove all the junk species. I've never seen them use the hack and squirt method, they cut all of the bigger junk out, skid it to a landing and feed it into the biggest chipper I've ever seen. My camp is a half-mile from the landing and it shook the place all day long. They blew the chips into semi's. At one point there were more than twenty of themed lined up on my little dirt two-track waiting to be loaded with wood chips.

After the sale and about a year before the good trees are cut they spray the entire area with round up or similar to kill all the underbrush.

pig castrator

Look up safety brush axe. That's what we used to use.
Silvex (2,4,5-T) was the herbicide before it was banned. It worked better than Tordon. With Tordon, you pretty much need to completely girdle the tree for it to work 100%.
With Silvex, you only needed 3 whacks evenly spaced around the trunk.