Susceptible Oaks All oaks are susceptible. Those in the red-black oak group (black, blackjack, pin, northern and southern red, scarlet, shingle and shumard oak) (Figure 1A) are extremely susceptible and can die within a few weeks of infection.
Red oaks are the most susceptible to oak wilt, will typically die within two to four weeks of symptom appearance, and can play a unique role in spreading the disease. Common red oaks in central Texas include: Spanish oak (Quercus buckleyi), Shumard oak (Q. shumardii), and blackjack oak (Q. marilandica).
Homeowners can reduce the risk of oak wilt infections by not pruning or otherwise injuring oaks after April 15. While high risk of infection decreases to lower risk after mid-July, it's prudent to simply avoid pruning oak trees from just prior to bud break to leaf drop. This means April to November.
According to the Sunset Western Garden Book, pin oak (Quercus palustris) keeps its brown leaves through the winter, but Northern red oak (Quercus rubra) loses them in fall. The retention of leaves in fall (meaning that they delay dropping them until spring) is a phenomenon called marcescence.
Hosts, Symptoms, & Diagnosis
It can be lethal to tanoak, coast live oak, California black oak, Shreve oak, canyon live oak, and madrone saplings, while it may cause only a minor leaf or needle disease for other hosts such as California bay laurel, coast redwood, and Douglas-fir.
The potential for spread of oak wilt through grafted roots is especially high after a diseased tree is removed or dies.
Live Oaks Have a Leaf Exchange in Spring
For many trees, dropping leaves is a way of preparing to go dormant during the cold winter months. Live oaks, however, can lose leaves throughout the year and generally stay green during the winter.
Northern pin oaks hold onto their leaves through the winter.
Tulip Poplars and Maple trees tend to snap, while Oaks and Hickory trees will uproot more easily, he said but it's rare. "That doesn't mean you have to get rid of those species by any means," he said. He suggests that homeowners simply get the trees inspected.
Trees in the red oak group generally die rapidly, usually within weeks or months after infection. Treatment will not save an infected red oak. Trees in the White oak subgenus, such as Burr oak and Chinkapin oak, can generally be treated for oak wilt and will recover within a year of treatment.
Yes, it is perfectly safe to prune dead oak branches any time of the year; however, please avoid cutting into live tissue around the bark collar and around the branch bark ridge.
If there is concern that a red oak may have been infected with oak wilt, then its wood should be immediately burned, buried, or chipped. Fire will kill oak wilt, and there is no risk of spores being transported by smoke.
Firewood from unknown origins should be burned during the winter months. If possible, do not store it to the next season. (Note: Burning firewood with oak wilt spores does not spread the fungus! Fungal spores burn, too.
Prevention. Oak wilt can be very expensive to control, but prevention is effective. To prevent oak wilt, do not wound oaks from April through July, which is when oaks are most susceptible to infection. This is particularly important in the high-risk area (see map on our Oak Wilt main page).
You can easily treat against infection and death of trees by oak wilt using DIY trunk injection of the fungicide Propiconazole 14.3 using reloadable Chemjet® Tree Injectors. The procedure is as follows for trees that have not yet been infected (indicated by leaves turning brown or falling off prematurely during summer.
How long do oak trees live? Oak trees can live for over 1,000 years; however, a more normal age would be around 600 years. It is said that an oak spends 300 years growing, 300 years living and 300 years in slow decline.
Shumard Oak Tree Key Features
Fastest growing red oak. This large red oak grows about 2 feet per year. Adaptable to any soil. The Shumard oak tolerates acidic, basic, compacted, clay, dry, wet, and even poorly draining soils.
Oak wilt is most active from April to July, which is why you should never trim oak trees in the summer. To be safe, you should avoid pruning between April 1 and November 15. Davey arborists recommend pruning oak trees between November 15 and March 31.
Answer: No. Live oaks can live for well over 60 years, often reaching 250-500 years in good growing locations. Maturity is reached by 75 years.
While most trees lose their leaves in the winter, live oak trees drop their leaves in January through February. Live oaks are not true evergreens like other oaks are. They will drop their old leaves in the winter and regain new ones in the spring.
Healthy oak trees are not susceptible to oak wilt in an infected area. Bur oak, white oak and other members of the white oak family are resistant to the fungus and can be planted in oak wilt centers. For additional prevention measures, plant tree species other than Oaks to guarantee no infection from the disease.
Finally, I'd like to note that chainsaws do not transfer oak wilt and are self-sterilizing on account of the operating temperature exceeding the temperature that the fungus can live in.
Once an oak tree is infected with the oak wilt fungus, the tree will die and there is no treatment to save the tree. When an oak wilt infection is confirmed treatment can be applied to the surrounding trees to prevent the spread of this disease.