Subpar Planting & Excessive Mulching

 In Education

    

While commonplace in the Upstate, this transplant (A) exemplifies all that is wrong with landscaping today. Millions of our Upstate trees die each year due to this barbaric practice!

While caring for other trees at this historic site, I noticed several installations with serious planting issues. As I approached this Ginkgo biloba ‘Autumn Gold’, I noticed the mulch piled high, and the root flares (blue-green arrow; B) buried out of sight. Mounding or ‘volcano mulching’, is an urban tree problem created by man. It does not occur in the forest. Not only does this cause trees stress, but it almost always results in girdling (slowly choking your tree to death) by its own circling roots, landscaping materials left in the hole, rotting bark on the trunk, and root rot moving up into the butt (blue arrows point to early butt rot; cracking}. http://greentreedoctor.com/girdling-3

There should never be soil, mulch or any other material piled over the root-ball, above the root flares, at least one foot out from the trunk, for the life of the tree (http://hort.ifas.ufl.edu/woody/over-mulching.shtml). Beyond a foot from the trunk, only 1 to 2 inches of single (or double ground), aged woodchip mulch should be used (http: //greentreedoctor.com/mulching).

Attempting to remove excessive mulch and soil years after planting can be a real chore. Cutting through roots, rocks, compacted clay soil, and landscaping materials (wire, nylon straps and burlap), is not for the faint of heart! With our safe, supersonic air tools, we were able to make quick work of this (B). This poor tree was buried in 9 1/2 inches of mulch and soil (a wheelbarrow load; white ‘X’). I see this all too often.

I learned from the Grounds Manager that the landscaper used premium, triple-ground bark mulch at $38 a cubic yard. That  much fine mulch intercepts most of the water from rainfall and irrigation, while reducing water and air to the critical root zone. The darker color can excessively heat up the critical root zone, killing roots, microbes and soil animals. And since bark has a protective wax, it breaks down more slowly, providing less immediate benefit to often depleted urban soils and stressed woody plants.

Several universities have found woodchip mulch (comprised of bark, wood and leaves; the whole tree) – the kind that comes out of tree service wood chippers – to be the best organic mulch for trees and shrubs (http://www.bigblogofgardening.com/why-wood-chips-make-the-best-organic-mulch). A secret within the Industry that you probably won’t hear from the mulch yards and landscapers, is that, “the cheaper the mulch, the better for your trees!” Many landfills, cities, counties, and tree services give this stuff away (you can tell we don’t sell mulch).

Needlessly piling mulch on top of mulch, year in and year out, when only 1 to 2 inches of mulch would have been much better for your trees (thinner mulch beds may require organic herbicide application), does not make good sense. Most large properties, and even many homeowners, needlessly spend thousands of dollars each year to kill their trees.

My examination does not stop here. When I applied pressure to the trunk, the entire tree moved at least a foot (I have it on video tape). After 2 years since installation, that is not good! This tells me that this plant is not established. Were it planted properly, within 2 or 3 months of installation (during the growing season), the lower trunk would be stiff as a board. Meaning that the roots have grown outside the planting hole, and have become anchored in the surrounding soil; less likely to fall over during a storm, healthier and more pest resistant because it is accessing more resources, with annual growth measured in feet, rather than inches.

How else do we know? I used a probe (B) to determine where the root-ball stops, and the planting hole begins. I also physically dug up the root-ball (the top of the wire cage is still there). But the real proof will show in 30 days. To correct this common mal-practice of “drilling ‘n dropping” into a tiny, deep hole – since it’s not practical to replant – we air-fracture the soil immediately around the root-ball. Within 30 days, 90% of the trees we treat (during the growing season), will be stiff as a board. The plants will be much healthier, and start growing to the heavens (ginkgo’s can get over 100 feet tall!).

BTW, after only 2 weeks, this tree was as stiff as a board, and shows new growth. In 3 months, it has grown a foot in height and 1/2 inch in diameter. This is no accident!

Though for 2 decades, we have religiously educated the public, and encouraged landscapers to plant properly (http://greentreedoctor.com/planting), the problem is only getting worse. It may take passing some laws to rid our beautiful Upstate of this scourge. But until the landscape changes, we’ll keep putting the word out, and correcting as many subpar transplants as we are able to (http://greentreedoctor.com/tree-profiles/#girdling).

 

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