I put 3 maples in about 2 years ago. 2 are doing fine but this one was not only a late starter but, as you can see, has only filled in the bottom third. I scratched the bare limbs and they show no green at all.
First, any suggestions why this would happen? All 3 get the same light, water, etc.
Second, should I prune back these dead branches? And is it best to wait till Fall/Winter?
Thanks in advance
Dennis
Without being able to do any close inspection, I'd hazard a couple opinions on what would cause such a drastic reduction in quality of performance out of an Acer rubrum, Red Maple.
•Flat-headed apple tree borers tunneling under the bark, which disrupt the trees cambium layer where nutrients and water circulate up and down the trunk. That would be my first and best bet.
•Girdling roots, which would be "strangling" the trunk below the soil surface, and causing the same disruption problem with the cambium layers.
Look for holes in the bark on larger branches and along the trunk. Also note sunken-looking areas - that'll show you where the borers have been active. If you can take pictures that show the trunk closely from several sides (and full length to the first set of branches), we might be able to e-diagnose the damage.
Finally: there is no inappropriate time to remove dead branches. If there is no green there, there is no coming back to life. And with that much dead wood, the tree is probably a lost cause.
Other possibilities are compacted soil, toxic builders rubble etc. buried where the tree was planted, and root damage when it was moved.
Resin
The other possibility is there was too much root damage on field-dig from the grower and it's finally showing the signs. If you purchased it as a container plant that wasn't field grown, could it have missed on the watering on planting or in the first summer?
I did find this one hole in one of the trees. That tree is doing OK. (for now). All the trees have the split in the bark. The only bugs I have found are "stink bugs". According to our local Clemson Univ. Extension, these are common and not something to worry about.
The girdling may be an issue. The grower said it is fine to leave the wire around the burlap when I planted them. I've since learned that may not have been a good idea.
"stink bug"
Split bark
It's true that the stink bug is innocous, but it did not make the "D" shaped exit hole that you illustrate with the crack in the bark. That's from one of the borers exiting as an adult.
Since you are familiar with your Extension Service, take a look at information about the flat-headed apple tree borer, insect pests of Acer rubrum, and/or borers affecting maple trees. I think you'll find ample evidence confirming what you have impacting your trees.
This is not an easy pest to prevent, or get under control once you have it. I think a systemic insecticide is about the only product available to homeowners to apply that might provide some control. And, it may be much too late for that one tree. The others may be worth the investment. You could also contract the services of a certified professional arborist to evaluate your trees and recommend appropriate treatment.
That last image is the classic look of borer damage. You can see new callous tissue (the tree forming new wood on the trunk alongside where the tissue was killed/eaten by the borer larvae tunneling underneath the bark). The bark is still hanging on there, but is providing no value to the tree. The stink bug is foraging for whatever stink bugs feed on - could be other insects hiding under the dead bark, or maybe some plant fluids seeping from the wounded area.
The only other common way you see this type of damage, is by overspray of herbicides like Roundup when used around the base of trees to eliminate weeds. The thin bark of young trees (Acer rubrum again being one of the most commonly affected, dogwoods another) can readily absorb Roundup through the bark, and the trunk cells are killed by it just like green leafy cells. This trauma to the trunk then provides entry to other opportunistic pests (like borers).
Gardeners also occasionally traumatize their young trees by mower or weedeater damage, or sometimes by the handling of the tree as it is being planted. This often goes unnoticed at first, and is most deleterious to young trees that are already stressed by transplantation (with B&B plants up to 90% of the tree's roots are left in the field nursery).
The advice to leave wire/burlap on the tree's root ball is somewhat off the mark. It is advisable to remove all the wire and burlap that is above grade (on the top of the ball) and any artificial non-rottable materials that would eventually restrict the growth of the trunk diameter. If you can remove all of it without damaging the tree's root system, that is best.
When planting, if the hole is dug adequately wide, there is room to place the tree's root ball at the proper height in the hole. Proper height means where the roots flare away from the base of the trunk. This is often buried several inches down in the root ball due to cultivation practices at the nursery where it was grown. Find this root flare and make sure it is at your surrounding soil grade. Then, stabilize the root ball (trunk vertical, if desired) with tamped soil, and then reach in and cut away the wire basket from around the root ball and discard. Then, the hole can be backfilled with soil to near the surface to further stabilize the root ball. Then, cut away or fold down all the burlap that is above the soil surface and bury it in the hole around the root ball as you finish backfilling. Keep the root ball good and moist during the entire establishment period, which is usually a minimum of a year per inch of transplanted trunk diameter.
Leave out any of these steps, and you hazard onset of pests as illustrated, or loss of the tree.
Since you are finding cracks and scars on several of your trees, I'd recommend highly getting the professional opinion. You spent good money getting those trees in the ground, and several years growing them this far. There is nothing more discouraging and off-putting to the gardener than to see valuable time/money go for naught.
I'd also suggest taking more pictures (including some that show the whole trunk from ground to the first set of limbs, and from various sides around the tree(s). It make seem redundant to some, but this thread can/could be a good primer to those millions of others who plant young trees but aren't aware of these issues or how to prevent them.
Thanks VV for such an informative answer. If only I knew now what I didnt know then...I am considering contacting a professional as you recommend. I do hope it is not too late.
Thanks again.
The damage in your images doesn't look familiar to me but the VV's planting instructions are "right on the money". The only thing I can add is using a sprinkler on the foliage as much as you can as transpiration and lack of roots can add to the decline after field-dig.
