When we were young, Mama took up the wool rugs every spring and put down straw ones. Just when we had the freedom to go barefooted, we suddenly had a horribly prickly floor that made sitting to play gin rummy or sprawling to watch TV a torturous experience.
For the plants we grow, however, a straw rug, so to speak, is a delight. Pine straw mulch is just about the best thing since sliced bread. It helps the soil retain up to 30 percent of its moisture, impedes compaction during heavy rains, and insulates the soil from temperature extremes. Pine straw needles weave themselves together in such a way that air and water can move through them easily; that same matrix also prevents a heavy rain or wind from scattering them all over the yard.
As they slowly decompose, pine needles add that always needed organic matter to our soils. These humus particles, combined with the earthworm activity organic matter encourages, improve soil tilth by creating tiny channels that facilitate air infiltration and root growth.
If you aren’t a believer yet, how about that pine straw is a renewable resource? Pines planted for timber naturally drop some needles each year, which can be harvested five times during a typical 20-year growth cycle without harming the trees themselves. The needles provide a home for beetles and other insects – the athletic brown thrashers and robins do kick it up somewhat to look for those tasty morsels.
Pine straw is an excellent barrier to keep weeds from growing. Placed around trees and shrubs (extending at least six feet from the center of trees, please) it protects that life-sustaining vascular tissue found right under the bark from injury due to lawn mowers or that instrument of the devil, weed eaters!
Scatter pine straw 3 or so inches deep in your beds and around trees; it should settle to around 2 inches. Don’t pile mulch around the trunks – keeping it several inches away will help discourage fungal or vole attacks. You can add a little new straw each year to retain that fresh, uniform look, being careful to keep it no more than 2 inches deep. Don’t panic if you are poking around and find a whitish mold towards the bottom of your older mulched areas as that is the natural and desired decomposition that releases small amounts of nutrients and organic matter.
Pine bark, a byproduct of the lumber and paper industry, also makes good mulch. The smaller pieces are less likely to float off than the nuggets, although they don’t stay put as well as needles do. It, too, will slowly break down and help add organic material to your soil.
What, you still want that dyed, ground-up wood business that stains your tennis shoes? Ground wood is high in carbon and cellulose. It’s very slow to decompose, lasts a long time, and often grows mushrooms. Sounds like less trouble and perhaps slightly romantic, doesn’t it – until your mulch sprouts a crop of stink horn mushrooms. If they appeared only once, it would be a curiosity, but they send up their vile smelling and often suggestively shaped fruiting bodies whenever the environmental conditions are favorable. I suggest that you keep your tennis shoes white, you nose and vision uncontaminated, and your commitment to sustainability unsullied by a judicious application of pine straw mulch.
Amanda McNulty is an associate extension agent for the Clemson University Cooperative Extension Service and is a co-host of “Making It Grow” broadcast weekly on ETV television stations. Website: www.clemson.edu/extension/hgic/