southern live oaks

For this brief owner’s guide to live oak care, I consulted with two professional arborists: horticulturist, arborist, and instructor, Jim Foret, who has extensive experience with old live oaks in the New Iberia area and teaches at the University of Louisiana at Lafayette; and Bob Thibodaux of Bob’s Tree Preservation in Church Point and Scott, LA. I asked them to address the importance of this distinctive tree species for Louisiana and to focus on its proper care and conservation. I’ve distilled their guidance into the following principles for live oak owners and caretakers.

Roots and soil—It takes room to grow a healthy tree, so don’t crowd your oak. Few people grasp just how large the functioning root system of a live oak really is—your oak’s roots do not stop at the end of its branches but generally extend one-and-a-half to two times the full spread of its crown.

Healthy root zone—Caring for your oak tree begins with creating the best conditions for a healthy root zone and lower trunk. Every square foot of undisturbed, uncompacted soil in an oak’s root zone is GOLDEN to the health of the tree. Caring for the “lower trunk” means keeping the above-ground root flare clear of leaves and soil that can eventually accumulate and weaken the root system.

Don’t fertilize and don’t use weed killers—Live oaks rarely, if ever, need any kind of fertilizer. What they do need is healthy soil. Using weed killers like Roundup or similar products kills more than weeds. These dangerous chemicals kill the fungi and microorganisms living in the soil that help the tree roots absorb and process nutrients and water. If you’re going to give the tree anything, add “mycorrhizal fungi” to the soil in the oak’s root zone. Mycorrhizae are nature’s root boosters, tiny fungi that work to help the tree roots absorb more moisture and nutrients.

Oaks don’t like soggy or compacted soil. They may tolerate it for a short time, but these two conditions block oxygen in the soil that an oak needs to thrive, and compacted soil makes it harder for oak roots to breathe and grow. Over time, these conditions can literally smother a tree. Don’t park automobiles or other heavy equipment under your oak. The weight will seriously compact the soil and kill vital root structures near the surface. And please, don’t slice large above-ground roots when mowing grass around your oak. This injures the root system and the wounds open the tree to infection and disease.

Balance—Live oaks are amazingly strong, within certain limits. The Creator designed them to grow in forests but people have stripped the forests. Today they are living along city streets, crowded between sidewalks and street paving, or they grow in groves where they can spread much wider, with multiple major limbs. You’ll also find them alone in fields of sugarcane, where they’re subjected to a variety of toxic fertilizers, weed killers, and other harmful chemicals. As a live oak grows, its long-spreading branches can become massive and sometimes can create an unbalanced, poorly rooted trunk structure.

Pruning—A balanced shape can improve an oak’s life span. Prune oak limbs (ideally when they’re young) to avoid imbalance, lopsidedness, and excessive limb length and weight that might literally pull the tree apart or uproot it as it grows. Prune dead wood seasonally, ideally during the dormant winter months when the oak is less active, NOT during the summer when untrained tree trimmers like to scout neighborhoods looking to make a quick profit from needless over-trimming of your oaks. Remember, never remove more than 10 to 15 percent of branch growth a year to prevent over-stressing and weakening your tree.

Leave the leaves on the tree—Your oak’s leaves, as with other plants, convert light (radiant energy) to chemical energy. Every leaf is important and necessary to your oak’s vitality. Leaves on the outside of the canopy are designed to absorb bright direct sunlight, while leaves growing inside the oak’s canopy are designed to extract the most energy from filtered light. Both types of leaves are crucial for your oak’s health. So prune carefully and cautiously and leave the healthy limbs and leaves on your tree.

Inspect your oak regularly—Look for signs of stress, bark lifting off in places, leaves dropping out of season, and crotches where limbs branch apart and might create pockets that can collect leaves and water that will eventually rot and weaken the joint.

If you’re fortunate enough to live in the company of live oaks, your life is blessed. And if you don’t live near a live oak, I strongly urge you to plant one, or maybe two or three.

Ascension Parish and Upper River Road

Ascension Parish has always been a sort of blank spot on my live oak radar. Before I began this 30-something series, I was unaware of the number of live oaks that live there. So, I’ve been surprised and delighted to have located several old and beautiful trees that have led otherwise low-profile lives in this historic parish.

The Martin Oak study 1 – 35' 6" in circumference

The Martin Oak, Gonzales, LA – 37′ 8″ in circumference

I’m not sure if I’ve emphasized enough in my earlier blogs how rare it is that 30-something-foot girth oaks have survived all of the changes that have taken place on the Louisiana landscape in the past 300 years. In her invaluable reference book, Louisiana Live Oak Lore, Ethelyn G. Orso describes the process of “live oaking,” a fairly common practice in the past in which woodsmen would cut live oaks and sell the wood to supply the wooden ship industries of Britain, France, Spain, and the United States.

The Martin Oak trunk and burls

Here’s an excerpt from her book on the subject:

“As early as 1709, shipwrights recognized that the near-impenetrable wood (of the live oak) was perfect for timbers and ‘knees’ for vessels. ‘Knees’ were the angular sections of wood taken from the joints between tree limbs and trunks. Such natural joints were stronger than any artificial joints made by shipwrights, and braced the sides of the ships… For the European governments that controlled Louisiana in that early colonial period, live oak wood was the state’s most prized natural resource.

Having practically deforested the European continent in search of the indispensable oak wood for their fleets, British, French, and Spanish rulers looked with greedy eyes to the vast expanses of live oak forests in the southern parts of what would become the United States. Those European governments that gained control of the part of ‘West Florida’ that today is eastern Louisiana claimed the live oak forests as state-owned resources. That led, by the mid-1770s, to a thriving illicit trade in live oak wood between the inhabitants of the area and whoever would pay for the poached wood. In 1811, after Louisiana had become a part of the United States, Louisiana Governor William C. Claiborne began communicating with the secretary of the navy in Washington, DC, and in 1817 an act was passed giving the president of the U.S. the authority to reserve lands with live oak forests for use by the U.S. Navy.”

It was hard times for large live oaks in those early years of the colony and the oaks that survived the wooden-ship era were still faced with the widespread clearing of lands for farming and ranching as well as eventual urban development. So, when I express respect and even awe at the few oaks that have managed to survive (and flourish in some cases) after 300+ years of cutting and clearing, you can understand why. Now, on to the 30-something oaks of Ascension Parish:

The Martin Oak, vertical view of trunk

The Martin Tree—(See photos above as well) #1405 on the Live Oak Society registry, this tree was registered with a circumference of 34 feet by Ms. Delba E. Martin. She was born in 1906 and passed on in 1995. With help from the Ascension parish assessor’s office, I was able to locate the property that was once owned by Ms. Martin and the tree is still there.

The shape of the tree trunk is similar to the Rebekah Oak and others—it has a very large burled lower trunk that tapers above 5–6 ft. from the ground. Generally, this is above the 4–4.5 ft. line where one would measure the girth, but with trees like this, I take multiple measurements above and below the 4.5 ft. line and make an average measurement. My estimated girth of this oak is approximately 37’-8″ and still growing.

John Hudson Oak, 29'-8" – Prairieville, LA

John Hudson Oak, #6350 – 29′-6″ – Prairieville, LA

The John Hudson Oak is located in Prairieville, LA at the Hudson House, a beautiful historic family home that’s been in the Hudson family for several generations. The John Hudson Oak is the largest and most impressive of numerous live oaks on the grounds. It has a lovely sweeping canopy that reaches to the ground on three sides. Mrs. Ellen Hudson Waller says that several other oaks on her property are Live Oak Society members.