LSU AgCenter horticulturist
Louisiana’s state tree is the bald cypress. Its scientific name is Taxodium distichum.
Bald cypress is one of our most distinguished native trees and is widely found in Louisiana landscapes. Native from the Atlantic coast west to east Texas and north to the middle of the Mississippi River valley, they are commonly associated with the swamps of the Gulf Coast region and offer many positive landscape attributes.
Bald cypress is a member of the redwood family, which are mostly evergreen. Bald cypress, however, is deciduous, losing foliage in winter. Trees can reach as tall as 100 to 120 feet at maturity with a narrow, upright growth habit. Some trees can have trunk diameters of 5 feet or more, but 2 to 3 feet is most common.
Bald cypress do best when planted in full to partial sun. They can readily adapt to highland and bottomland areas and, once established, can tolerate standing water. In other words, they have the ability to adapt to wet and dry soil conditions and varying soil textures. Bald cypress also will grow in compacted soil.
Interest in bald cypress as a landscape tree is considerable. Many landscape horticulturists use this tree in their plantings, and it is one of the top five tree species planted in Louisiana. Trees are available at garden centers in sizes ranging from 3-gallon to 30-gallon containers.
Bald cypress are fast growing for the first 10 years in the landscape. After planting, they should be fertilized annually in late winter or early spring for the first 3 to 5 years with a balanced fertilizer such as 8-8-8 or 13-13-13. You can fertilize every 2 to 3 years thereafter assuming your native soil is moderately fertile.
Bald cypress trees have “knees.” These are cone-shaped structures that grow from underground or submerged roots. Knees are more prone to develop in clay soils than in silty or sandy soils. Also, knees are more prone to develop on trees growing in water than on trees growing on dry land. Once an individual bald cypress tree begins producing knees, this modified structural growth will continue even if knees are continually cut out.
Louisiana has the national champion bald cypress. Some beautiful trees more than 1,000 years old are located at Cat Island National Wildlife Refuge located in a bend in the Mississippi River just north of Baton Rouge. The area floods during portions of the year, but the national champion tree is accessible during dry times. The tree is 83-feet tall with an 85-foot spread, a diameter of 16.5 feet and a girth of 49 feet.
Other trees similar to bald cypress are planted in Louisiana.
A botanical variety of bald cypress called pond cypress (Taxodium distichum var. nutans) has finer-textured foliage than bald cypress and is more upright. Foliage color can be attractive with new growth in spring, and most trees have rusty brown fall foliage that lingers into early to mid-December in south Louisiana.
Montezuma cypress is another variety to consider planting, but these are not as readily available at Louisiana garden centers. These bald cypress relatives have no knees.
Considerable research and selection are continuing in the world of bald cypress, and we expect to see improved forms of this great plant being introduced shortly.
Bald cypress provide a number of great benefits. So consider adding Louisiana’s state tree to your landscape. September through November is a great time to plant one.