Does your tree have oak wilt?
Spring cleanup is a great time to check plants and trees for damage that happened over the winter. It’s also the perfect time to look for signs of diseases, like oak wilt. Robert Spartz, district manager for the Davey Tree Expert Company in Eldridge explains this danger to oak trees has been in the area for years.
“It’s a disease that gets within the tree,” said Spartz. “It’s actually mostly transmitted by boring insects and can also be transmitted through root grafting through common trees if they’re the same type. If they get infected with oak wilt, the root systems from that tree can spread to another red oak that’s next to it and pass it on that way. It is it’s a vascular system clogger; in layman’s terms, it’s very easy for all the vessels in the tree to get clogged up. That doesn’t allow for water and nutrients to be transported up into the tree or to certain parts of the tree.”
That’s not the only problem facing oaks in the area. “We are dealing with a lot of issues with oak trees right now, a lot of borer activity even though it’s not the same borer that’s transmitting oak wilt. We’re starting to see a severe decline with white and burr oak trees as well.” White oak trees don’t seem to be affected by oak wilt as much as red and pin oaks, he said.
There are treatment options for trees infected with oak wilt, as well as therapeutic treatments, but tree owners must commit to them every two years for the life of the tree. “That would be a good route to go for somebody who has a very high value oak tree or a lot of trees on their property that they want to protect.” Signs of wilt aren’t an automatic death sentence for the tree, said Spartz. “If it’s just maybe one branch that’s flagging, maybe starting to show signs of oak wilt, we could potentially prune that off. The growing season is really going to be the only time that you’re really going to be able to see that. That would be the one time that we would really say it’s OK to prune oaks outside of the winter. Oak wilt is really the main reason we only prune oaks during the winter.”
Spartz says the margins, or edges of leaves are a good indication of the presence of oat wilt. “It almost looks like a like a scorching or a burning effect on the outer edges of the leaves that kind of start to desiccate and die back towards like the veins of the leaf.
Keeping your trees healthy is the best defense against oak wilt, said Spartz. “Keeping the vigor up in the tree is a term we use a lot, making sure that during stress periods, when we’re going through droughts, we’re watering those trees even though they’re big and old and they look healthy. They could start to stress out and the less stress that the tree has, the less unlikely these boring insects are going to want to come to this area.
Luckily, the Quad Cities isn’t in the middle of an oak wilt epidemic. “Right now, our levels are still kind of low to moderate, so it’s not really like extremely high pressure that I’m noticing right now,” said Spartz. “More cases are possible but haven’t been reported; some dead trees in wooded areas may have been victims of oak wilt. However, there’s no danger in burning wood from a diseased tree. “If you’re just stacking wood that’s infected and leaving it there potentially to burn it later, if you have other oaks around the area because one thing that you’re allowing to do is maybe the beetle larvae to hatch out of the tree and then fly to another tree.”
Property owners who suspect oak wilt need to contact a professional, said Spartz. “My first recommendation is going to be to call a certified arborist to come out and take a look at the tree and give them an assessment on the tree itself.” He stresses best practices for protecting trees, such as watering, improving the soil with organics and fertilizer. Mulching around trees not only conserves water but keeps mowers and weed trimmers from getting too close to protective bark. Any type of mulch will work, including hardwood chips. “Most hardwood mulches are perfectly fine to use. I would say the odds of there being something there that was a problem are very minimal. Good soil microbial activity is what mulch is going to promote and is very beneficial to trees from a food source standpoint and it also helps with water retention.”
For more on oak wilt, click here.
For the latest news, weather, sports, and streaming video, head to WHBF - OurQuadCities.com.
