The southern live oak, this week’s plant of the week, is a majestic tree that can be seen throughout the Texas Hill Country. This live oak species only grows in the south because it is not very tolerant of freezing temperatures. Southern live oak, Quercus virginiana, is not a tall tree but is one of the broadest spreading of the oak species. All of its wood mass is located in the branches, which form a widespread canopy averaging about 80 ft wide- talk about great shade potential! The lower hanging branches plunge towards the ground before bending back up to the sky making it a beautiful ornamental tree for your outdoor space.
The elliptical shaped, leathery leaves of the southern live oak are dark green on top and a light gray underneath. Unlike most other oak trees, Quercus virginiana is mostly evergreen. These trees will only loose their leaves for a brief period in the spring right before new growth appears. The flowers appear in spring, but are not colorful and showy like other flowers I have previously described. The reason is that southern live oaks are pollinated by the wind instead of insects and birds, so there is no need to waste energy on big attractive flowers. Quercus virginiana produces acorns in September. These acorns fall to the ground around December and are an important food source for birds, squirrels, deer and other small mammals. Native Americans would extract a cooking oil from the acorns. The wood of southern live oak is very heavy and extremely hard which makes it difficult to work with. However, back in the day of wooden ships, live oak wood was the primary material used to build boat frames because of its unmatched strength.
Sadly, oak wilt, a devastatingly aggressive disease, threatens the population of live oak trees in Texas. Oak wilt is caused by a fungal pathogen that invades the water transport systems, or xylem, of the tree. The tree produces defensive structures in the xylem to minimize the spread of the fungus, but overtime these structures, in combination with the fungus, block the waterways to the leaves. When the leaves don’t get the water they need, they droop and die giving the oak canopy a wilted look.
Come take a walk through the gardens this week to see some southern live oak trees.
Republished with permission of the Goldthwaite Eagle. By Savannah Lane.