Tree wound dating
If a tree is wounded, seal the wound quickly (within 15 minutes) with one coat of shellac (preferable) or a water-based paint.
Fourth, do not move firewood from oaks that have died from oak wilt off of or on to the property in question.High Risk months in Minnesota are typically April, May and June.Low Risk months are March, July, August, September and October. First, is the fungus that actually causes the disease active?However, since it could happen, it’s best to delay pruning of the oaks until the Safe period or to quickly seal the pruning wounds with shellac or paint to avoid attracting the beetle if pruning during the Low Risk period is unavoidable. When this happens, fluids can pass from one oak to another, including fluids that carry the fungal pathogen.During the Safe period, there is virtually no risk that an oak can become infected with oak wilt by over-land transmission of the fungus. Oak wilt spreads from one area to another (distances greater than a quarter mile or more) via the beetles carrying the fungus. Oak wilt is a fungal disease that kills thousands of oak trees every year.
Oak wilt spreads in two ways: Through root grafts between similar species, radiating outward from a central infected tree; and over land, carried by oak sap beetles carrying fungal spores from tree to tree. There are three risk season timeframes: High Risk, Low Risk and Safe.
Second, and especially important if oak wilt is established in an oak woodland, prevent the spread of the pathogen through root grafts by cutting through the connecting roots using a vibratory plow.
This will need to be done by a professional, preferably a Certified Arborist and if done correctly is a very reliable technique to reduce the amount of oak wilt spread.
Once the disease is established in a tree, it spreads from that tree to others via root grafts. The red oak group (red, black, Eastern pin, northern pin and scarlet) are more seriously affected by the disease-causing pathogen.
Once infected, they do not recover and die very quickly, often within 4-6 weeks of infection during the growing season. A qualified tree care professional will prune out the dead wood (if the disease hasn’t progressed too far) and if licensed, inject the tree with a systemic fungicide.
They refer to the probability that oak wilt will infect a tree.