‘Fungus’ not really a fungus

Q. I’ve lost lots of trees in the past couple of years. They are huge trees! They all get a creeping, white fungus after about one year, then the tree dies. Can you tell me what is happening?

Tifany from Youngstown

A. After speaking with Tifany, we decided the white “fungus” was not a fungus at all. The growth is really called lichen. It is a peculiar growth that is a result of a fungus and an algae coming in close association. It is actually a sign of good air quality. It does not harm trees.

Many people are unfamiliar with lichen, depending on how often they experience nature. Even if you are a nature enthusiast, it can be confused with diseases. The way to tell the difference? Look at both dead and live trees in the area. Lichen can be growing on both. Lichens are generally a pale green color and have crinkly edges. If you pull it off a tree, you’ll notice it doesn’t penetrate the bark. The bark under lichen will be perfectly healthy. Rejoice in the presence of lichen!

You can see photos of different types of lichen and learn more at http://go.osu.edu/lichen.

Now, about the dead trees: If the lichen are not killing them, what is?

The emerald ash borer (EAB) is the culprit! EAB is an invasive insect which affects only ash trees. Over the past few years (and mostly the last two), this insect has killed many of our ash trees all over Ohio, including the Mahoning Valley. It started its path of destruction when it was accidentally introduced from Asia into the trees of Southwest Michigan in 2002. In just 13 years, this insect has had a devastating effect on our ash species.

Ash trees are the most common tree in our urban forests. While the EAB has been in our area for the past eight years, some are just noticing the devastating impact. Even a healthy tree can die in as quick as one to three years, depending on the size of the tree. The quick death is due to the way the insect feeds. It tunnels just under the bark, disrupting the transport of water, nutrients and carbohydrates.

Dead trees in your yard should be removed promptly, as they are a hazard to people and property. Be sure to get estimates from multiple companies before making a decision on who to hire. Work with your neighborhood to see if you can get one company to get all the ash trees at one time as a potential cost savings for everyone. To learn more about removal, go to: http://go.osu.edu/ashremoval

You can find out how to tell if your tree is ash, learn about the insect and get ideas for replacement trees on our website at: http://www.emeraldashborer.info

Eric Barrett is OSU Extension educator for agriculture and natural resources in Mahoning County. Call the office hotline at 330-533-5538 to submit your questions. Regular clinic hours ended Oct. 31, but you can still call and submit questions. Hours vary throughout the winter season.