Damon Abdi and Jeb S. Fields
A healthy canopy is essential to the growth and development of the live oak (Quercus virginiana), supporting the leaves that are responsible for photosynthesis. Glucose, the sugary sustenance necessary for growth, is created through the photosynthetic process where carbon dioxide from the atmosphere is accumulated and transformed for plant use. Taking measures to ensure the health of the canopy can support this process.
Managing the canopy of a live oak requires patience. Newly planted live oaks should be pruned with one main intention — to support the growth of a prominent central leader. As the tree matures, pruning should be done with a focus on the future form and habit of the lateral branches. Pruning should be done to remove branches afflicted with at least one of the four “D’s” — those that are dead, dying, diseased or damaged. Special consideration should also be given to branches that appear to be struggling under the weight they bear, both for safety reasons for the public and to prevent deadwood snapping and inviting disease into the wound. You may notice some branches resting upon the soil surface, but do not be alarmed. When taking care of these areas, use precision and caution when mowing to avoid any harm.
While the graceful canopy of the live oak is renowned for its strength and is often cited as one of the most hurricane-sturdy landscape plants, there are steps that can be taken to offer support in the landscape. Developing a strong central leader is paramount to the long-term life of a live oak. For newly planted live oaks it may be advisable to put braces and supports on the central leader, especially during hurricane season, until the tree establishes itself in the landscape. As the tree matures, the sweeping branches (particularly those on older trees that have willingly weathered years of wind and hot Louisiana summers) are commonly seen in the landscape supported by posts, beams, cables and other structures designed to provide a perch for this popular plant to rest upon. This extra effort can ease the burden on these branches; however, to ensure safety and the health of both the tree and the individual protecting it, soliciting the services of a trained, licensed professional to perform these protective measures is recommended.
Perhaps one of the most eye-catching features found on live oaks is the Spanish moss that gracefully adorns the canopy of this tree. Spanish moss (Tillandsia usneoides) is an epiphytic plant, meaning it uses the tree it so delicately drapes solely for structural support. Self-sufficient, Spanish moss poses no parasitic threat to live oaks, gathering nutrients and water from the humid conditions that embrace this epiphyte without harm to its host. While Spanish moss is unlikely to take over a tree to the point it is considered damaging or aesthetically deleterious, it is wise to remove excessive amounts from branches to reduce their susceptibility to snapping. If this course of action is pursued, then removal by hand is the preferred method. Professional arborists often use an array of tools and equipment to access the hard-to-reach corners of the canopy.
The Louisiana landscape showcases many plants that represent the region, but few as instantly recognizable as the live oak. Using these measures to properly care for a live oak can reduce the risks of disease, damage and unsightly aesthetics in the landscape.
By taking the time to properly maintain the canopy of this majestic tree, future generations can stay true to their roots and carry on the heritage of this historic Southern hallmark.
Best Practices for Live Oak Canopy Management
Damon E. Abdi is an assistant professor of landscape horticulture, and Jeb S. Fields is an assistant professor and ornamental horticulture specialist. Both are at the LSU AgCenter Hammond Research Station.
This article appears in the summer 2023 edition of Louisiana Agriculture magazine.
The sprawling habit of the live oak (Quercus virginiana) invokes feelings of nostalgia among residents of Louisiana, as this Gulf Coast classic quintessentially defines a region. Often, the first thing people pay attention to is the thick lateral branches, reaching in all directions and casting an imposing, yet welcoming shadow over the landscape. Photo by Damon Abdi
Delicately blowing in the breeze, Spanish moss is haunting to some and heartwarming to others and creates a pleasant imagery for a bayou backdrop. This moss poses no parasitic threat to the tree, but excessive amounts of Spanish moss should be removed. Photo by Damon Abdi
Developing a strong central leader is important for the long-term life of a live oak. For newly planted live oaks it may be advisable to put braces and supports on the central leader, especially during hurricane season, until the tree establishes itself in the landscape. Photo by Damon Abdi