Mulch Right

We had several very large branches removed from a couple of the old trees on our lot, and decided to keep the mulch for use around some of our trees.

This situation presents the opportunity for me to offer a short lesson in correct mulching.

Frankly, mulching ones trees properly is critical to the health of your trees -- or, perhaps I should say that incorrect mulching can kill trees.

Leaving the grass growing right up against the tree is problematic for many reasons, including:

- you risk mower damage to the trunk,

- if you fertilize or use herbicides on your lawn, you kill the beneficial soil organisms that the tree needs to take up nutrients from the soil, and

- you compact the root zone through continued traffic with a lawnmower.

Here are a few tips on mulching well:

1. NO MULCH VOLCANOES. Never, ever pile the mulch up in a hill around the trunk of the tree. This all-to-common mistake promotes root growth into the mulch, which weakens the tree. It also invites insects and rodents to feed on the smothered bark.

2. To keep weeds from growing up through the mulch, lay down several layers of newspapers in the area where the mulch will be placed. 6-10 layers of newspaper will smother the grass and weeds, but still allow water to soak into the ground, and permit the soil to breathe. The newspaper will break down over a year or so, and you will be left with a rich humus (organic soil) under the layer of mulch.

3. Pull grass and weeds out from the area next to the trunk before mulching. This step will save you work later, because sure enough, the first place weeds seem to show up is right next to the trunk -- unless you clear them out prior to laying down the newspaper and mulch.

4. The mulch should create a bowl of sorts -- thickest in the area furthest from the trunk. Think of the bowl as a way to ensure that water won't runn-off away from the tree, but will soak into the ground nearest to the trunk.

5. The mulched area should be at least three feet around the tree for oaks and hickories to protect the densest section of roots from compaction and disturbance. I have to admit that because of time, the mulch circle shown here extends only about 2 feet from the trunk.

After getting a good ring of protective mulch around the tree, then it is time for installing native plants under the rest of the tree's canopy! But that's a lesson for another day !!