Tree and Shrub Disease

Oak Wilt affects all species of oaks, including: Red, White and Texas Live oaks. The fungus is transferred through two ways; underground through the root system or though insects. There is no cure for this disease, if you think you trees may be suffering from Oak Wilt, contact us for a technician visit to ensure proper identification. The best solution is to create a barrier between healthy trees and infected trees whose root structures do not meet.

The fungus can also be spread by insect activity. As sap-feeding beetles or oak bark beetles feed on diseased trees they pick up and become a vector of the disease which they transmit to healthy trees as they go to feed again. This may spread the disease a mile or so.

Red Oak Symptoms: Rapid leaf discoloration and wilting starting from the crown of the tree and working down (in our area, this disease is active from June-July). As the disease progresses, individual leaves turn bronze from the margin in. Dead leaves will fall off the tree and within a matter of a few weeks; the whole tree could be defoliated from the oak wilt onset. Red oaks (black, red, pin, scarlet) are the most susceptible to Oak wilt.

 

White Oak Symptoms: White Oaks exhibit the same symptoms as Red Oaks, though the disease progresses much slower by one branch at a time (may take years for the White Oak to die-out due to Oak Wilt). White oaks (bur, overcup, post, white) are more resistant to oak wilt than Red oaks.

 

 

Texas Live Oak Symptoms: Depending on the timing and weather conditions of the infection, Texas Live Oaks can die slowly or rapidly. The visual signs of Oak Wilt on a Texas Live Oak differs from the signs one would see on Red or White Oaks. Leaves will develop yellowing veins which turn brown. The disease will start at the top of the tree and work it’s way down defoliating the tree as it moves.

Bark may also show symptoms. Masses of fungus, known as a mat, can form between the wood of the tree and the bark. As the mat accumulates, the center may push up against the bark causing a crack and bleed out sap. The above mentioned insects are attracted to the scent of this sap.

Disease Development Favored by: Cool wet weather Corrective Measures: Destroy trees that are dead or dying from Oak Wilt Create a barrier between roots of infected and healthy trees Prune healthy trees in late summer
An oak defoliating from oak wilt	Fungus spores under the bark