Cypress: From Wetlands And Wildlife Habitat To Flowerbeds And Front Yards
April 11, 1996
GAINESVILLE—Cypress mulch, commonly considered the “Cadillac” of mulches, is widely used in professional landscaping plans and the yards of Florida homeowners. But at what price?
Cypress trees, found only in wetland areas, are cut for both lumber and mulch, and are a disappearing natural resource in Florida’s ecosystems, says Jerry Kidder, an extension soils specialist with the University of Florida’s Institute of Food and Agricultural Sciences.
“People need to realize that what they are using today is a very dear resource,” Kidder said. “Their kids won’t get to see any big stands of cypress, because they’ll all be cut.”
All too often cypress mulch is specified in landscaping plans because it is seen as a premium mulch, Kidder said. He is concerned about the use of cypress because they are slow-growing trees that only grow in freshwater swamps. They are not replanted as a crop like pine trees and are not an invasive, exotic tree like melaleuca, both of which could be used just as effectively for mulch.
“There is an irony here. Mulching is more popular than ever, but it seems we’re hurting the environment so we can help the environment,” Kidder said. “Some of the lumber waste used for cypress mulch is encouraged by the tremendous market for the mulch. But it’s not just waste being used, it’s also the new growth in the stands.”
Most cypress trees large enough to be cut for timber are at least 40 to 60 years old. While the softer edges and tops of the timber can be used to make mulch as a byproduct, a large consumer demand for the mulch also encourages the cutting of young, small trees, Kidder said. Once harvested, cypress trees don’t regenerate quickly.
Susan Vince, a visiting assistant professor in UF/IFAS’ School of Forest Resources and Conservation, said that clear-cutting is the most common logging practice used in cypress swamps, meaning that all the trees are cut regardless of size or age.
Sometimes the larger trees are used for timber, but often all sizes of trees are fed into chippers for mulch production.
Besides being prime habitat for woodpeckers, wood storks, several types of owls, opossums, bobcats and wood ducks, cypress swamps also help purify water by taking up nutrients.
“It’s important for people to realize that cypress swamps provide services that are important to society, like water storage, water quality enhancement and wildlife habitat,” Vince said. “While some evidence suggests that cypress swamps will regenerate following clear-cutting, this process is not certain and it may be slow. If swamps are intensively harvested over large areas, we may lose, at least temporarily, those important services of cypress swamps.”
Consumers often buy cypress mulch under an outdated assumption — that it is more durable and longer-lasting — though this is probably not the case, Vince said. That belief is based on stories of the larger, old growth cypress trees harvested in the late 1800s and early 1900s, which are no longer found in the state. The heartwood of those older trees contained chemicals that acted as preservatives, resulting in greater wood durability and rot resistance, Vince said.
“The younger trees cut today for mulch don’t have the heartwood that those old trees had,” Vince said, “so today’s cypress mulch is not likely to be longer lasting than any of the other mulches. I think that the aesthetics of cypress swamps is reason alone that they should not be clear-cut for mulch production. Really we should be using other sources of mulch such as pine bark, a byproduct of the pulp industry, or waste wood, rather than deliberately cutting cypress for mulch.”
Despite its dramatic appearance at the time of application, the softer wood used for cypress mulch fades fairly quickly and is washed away by rain. The benefits of being a hardwood, such as termite resistance and durability, are short-lived, Kidder said. Homeowners commonly use the cypress mulch, become unsatisfied with its attractiveness and buy more to replenish the area.
“Such a valuable byproduct just helps to create a larger market,” Kidder said. “There lies our concern for the state’s cypress supply. Large cypress stands could be found earlier this century, but they’ve been harvested. Both the trees and stands we have now are smaller, and we may never see large stands like that again.”
Among the alternatives to cypress that can be used for mulch are melaleuca chips, pine nuggets and pine straw. The use of melaleuca would be wise, since it is an unyielding tree invading more than 500,000 acres of Florida’s wetlands. Kidder also encourages homeowners to recycle waste already present in their yards, such as tree leaves, twigs and plant trimmings. “Mulching is good, but it doesn’t have to come out of a bag,” Kidder said.
In a study funded by the UF/IFAS Energy Extension Service, horticulture extension agent Gary Brinen and other staff at the Alachua County Cooperative Extension Office compared the effectiveness of alternative mulches with that of cypress, studying 15 different kinds of landscaping mulches over a six-month period. The results of the research showed three alternative mulches — wood chips, pine bark and pine straw — rated just as high as cypress.
“Both landscapers and homeowners were involved with the study, and both lost their biases for cypress mulch,” Brinen said.
All of the mulches faded over time, and the wood chips lasted longer while several others held up as well and looked just as nice over time as the cypress. Other recent UF/IFAS research showed that cypress mulch, when used in full sunlight, can form a type of crust that restricts water movement and reduces the amount of water received by plant roots.
No proof has been established on the prevention of pests by the hardwood cypress mulch, Brinen said, since all mulches are loose enough not to attract termites, which tend to stay in the ground or go to solid hardwood.
“The important thing is to use mulch, but we prefer recycled materials which are just as effective and just as attractive,” Brinen said. “Cypress is a resource that will become scarce, and it is very important to the ecosystem.”