"Free" is a powerful word and easily misused, but such a welcome gift when it's real.

The trees are giving one such gift right now, if you think about the fact that composted autumn leaves are worth the price of many fertilizer bags next year. How to cash in on leaves? There are five ways, by my count.

The most passive is to place leaves in piles to decompose slowly over 12 to 18 months. This method is good for wooded areas since tree roots are adapted to living beneath leaf duff. This isn't recommended for lawns or garden beds, though, because unshredded leaves are too dense.

A somewhat tidier method is to shred leaves with a mulching mower or a shredder and add them to a compost pile. Added in correct proportions with green materials, leaf mulch contributes to "hot" composting and produces wonderful soil amendments. The Connecticut Department of Energy and Environment Protection offers online videos explaining the process. (See link below.)

Yet another method is to run a mulching mower over the lawn and allow leaves to decompose in place. This method is favored by Linda Lillie, president of Sprigs & Twigs, a Gales Ferry landscaping firm, who says it fits well with the organic approach to lawn care.

"Shredded leaves decompose quickly into the lawn and add organic matter," she says. "It also makes it more difficult for grubs to move around in the lawn next spring."

In addition to shredding on the lawn, I personally favor "sheet composting." There are several ways to do it:

Sheet composting 1: Clean debris out of veggie beds. Then spread shredded leaves in a two- to four-inch carpet over the bed. Leaf-to-soil contact will cause decomposition over the winter and create a great planting zone for the spring.

Sheet composting 2: To create new beds or clear patches of lawn ready for spring repair, try this approach. Layer leaf mulch over non-corrugated cardboard or newsprint; this smothers existing vegetation during the winter. (Black-and-white or unprinted newsprint is safest, but check your newspaper's website for information about the composting status of its color printing.)Leaves are also a very safe source of fertility. Excess phosphorous has become a recognized source of water and soil pollution in recent years, highlighted by the state's new phosphorous law. Dawn Pettinelli, manager of UConn Soil Nutrient Analysis Lab, points out that leaves add negligible phosphorous. "Leaves are also relatively free of weed seeds," she adds, "unlike some other sources of fertilizer such as manures."

But there are two persistent myths about leaves that need to be dispelled.

Myth 1: Many believe that oak leaves and pine needles make the soil acidic. "They do not make the soil acidic," says Pettinelli. "When you compost them, the biological activity turns them to relatively neutral pH around 6." That pH is good for most things we grow in home gardens, she says, including flowers or veggies.

How did the myth get started? "Most likely, because oaks and pines live in acid soil, people think their leaves will impart acidity elsewhere," she says. "It's not true."

Rather than avoid using leaves, Pettinelli concludes, remember to get a soil test. "If the soil is too acid, there's always lime." (See links below.)

Myth 2: Many think that bark mulch is superior to leaf mulch. In reality, a two- to four-inch layer of shredded leaf mulch is an excellent alternative. Some feel that leaf mulch is too light for beds and borders and worry that it will blow around. I've personally used leaf mulch this way for 15 years, though, and can say that a little moisture from a hose or from the sky packs it down immediately.

TO LEARN MORE ABOUT LEAF COMPOSTING, SEE THE DEEP VIDEO ONLINE AT 1.USA.GOV/19V7GLL.

TO GET A FREE SOIL TEST, VISIT THE CONNECTICUT AGRICULTURAL EXPERIMENT STATION AT 1.USA.GOV/1AMIYJD.

KATHY CONNOLLY IS A LANDSCAPE DESIGNER, GARDEN WRITER AND SPEAKER FROM OLD SAYBROOK. EMAIL KATHY@SPEAKINGOFLANDSCAPES.COM FOR MORE INFORMATION OR SEE HER WEBSITE WWW.SPEAKINGOFLANDSCAPES.COM.