Mulch is like gold in the landscape. It solves many problems and prevents even more, so your trees are healthier and your landscape looks better. Before you begin, remember that there's a right way and a wrong way to mulch your trees. You can hire a tree care service, such as Lawn-Tech, Ltd., to handle your mulching needs, and you can maintain it between service calls. Read on for basics on function, types, and application.

How Mulch Helps

• Mulch insulates the soil, so the roots aren't exposed to freeze-and-thaw cycles in the winter.

• It slows evaporation from the soil, resulting in less water loss. Mulched trees can better survive drought, and they won't need as much water.

• Weeds can't grow as readily in a mulched area, so proper mulching prevents ugly weeds that compete with trees for water and nutrients.

• Grass and other plants often grow poorly or appear patchy beneath a tree, so mulch can give a cleaner, more polished look.

• Mulch provides a buffer between the tree trunk and the lawn. You won't need to mow close to the trunk, so mechanical damage is less likely to occur to the tree.

Types of Mulch

For deciduous trees, the best type of mulch is shredded bark, bark nuggets, or wood chips. Generally, cedar or hardwoods are used for mulch. Cedar and redwood mulch has a nice color that fades slowly, while other hardwoods eventually age to a silvery gray. Avoid using black walnut for mulch. It contains a chemical that can harm or kill a tree. Tree service providers sometimes supply their own mulch, chipped from trees they remove. You can request a specific variety, if desired.

For pine trees and other evergreens that grow well in acidic soil, you can use pine straw as mulch. Pine straw is simply dried pine needles. They retain their color well, so they look good all season long.

Application Basics

Generally, the area mulched depends on the size of the tree. For best results, the entire root zone benefits from mulch. The root zone stretches out to the outermost edge of the tree canopy, so this may not be viable on large trees. If you mulch a smaller area, try and cover the soil at least 3 feet out from the trunk.

The basic mulching steps are as follows:

1. Clear turf, weeds, and other plants from the ground, baring the soil. Avoid digging too deeply into the soil, or you may damage tree roots.

2. Spread the mulch out in a 2- to 3-inch deep layer. Any deeper can smother the roots, while a shallower layer doesn't retain moisture, insulate, or suppress weed very well.

3. Pull the mulch back 3 inches from the tree trunk. If the mulch rests against the tree, it can trap moisture and cause the trunk to rot.

Mulch will need to be replaced annually in spring, because it naturally decomposes. The decomposed mulch does add nutrients to the soil, though. If you're worried about the mulch spreading into neighboring grass, install an edging strip around the perimeter of the mulched area.