Saturday, October 29, 2011

Planting a Tree

I am not a tree expert but even I can tell something is wrong here.
Several years ago I learned about a tree’s root flare – the slightly wider part of the trunk directly above the roots. The root flare should be visible just above the soil surface. It’s the level that allows the tree to grow best. 
If a tree is planted too deeply it can encourage girdling roots (roots that go around the tree instead of out or down). Girdling roots will eventually stop the flow of water and nutrients up the tree.

Tree with girdling root (lower right) at top of mulch volcano.

Currently popular, mulch volcanos (mulch piled in a cone shape around tree) may damage tree bark and are places for insects and disease to enter. Mulch volcanoes cover the root flare.

According to Martha A. Smith, Extension Educator, Horticulture, University of Illinois Extension:
“A mountain of mulch, piled high against a tree trunk will not kill the tree immediately – it results in slow death. Homeowners don't associate their actions with tree decline several years after they over mulched a tree.”
Mulch volcanoes may also cause the roots to surface in search of oxygen as in the top picture.

Tree with bark damage at base on top of mulch volcano.

Mulch is useful to keep moisture in the soil and keep the weeds down. But mulch needs to be 2 to 4 inches thick kept an inch or two away from the tree bark. Trees are expensive to buy and plant. Why not give them the best chance possible.
It is a shame to see such beautiful trees may be doomed. With a lot of luck they may last a while. It would be nice if they would last 100 years.

Information on tree planting from Penn State College of Agricultural Sciences “Planting Ornamentals”. 


donna said...

I'm assuming it was city workers that mulched the trees like that. Seems like they would know better. Good information, Marie.


Marie said...

Hi Donna,
I don't believe the city workers did this. The top picture is actually in the yard. I think it we either a landscaper or the homeowner. What a shame.

Darius Adlam said...

That tree looks like it's having a hard time breathing. Planting a tree properly in our backyard or in our neighborhood is beneficial aesthetically, and the act shows love for the planet. Trees can serve a decorative purpose planted in our neighborhood or anywhere else. Trees also help reduce contaminants in the air by absorbing carbon dioxide and releasing oxygen. Also, a tree helps absorb water and prevent erosion.