Large Oak Trees suddenly falling - Ask Extension
We live in rural Northern Baltimore County. Our lot is almost 4 acres and is about 70% wooded. Over the past several years, we have had a lot of o...
Knowledgebase
Large Oak Trees suddenly falling #876238
Asked July 07, 2024, 8:31 PM EDT
We live in rural Northern Baltimore County. Our lot is almost 4 acres and is about 70% wooded. Over the past several years, we have had a lot of our large oak trees come down naturally, splitting about 1/3 up the trunk. Sometimes during a storm, sometimes, with no warning. This happened again last night. I notice that neighbors seem to have had a lot of tree removal as well, and wonder if there is a disease causing oaks to rot from inside, as usually they look OK from the outside.
Baltimore County Maryland
Expert Response
There is no single disease causing this condition, and it's surprisingly not uncommon for wood failure and sudden breakage to occur in mature trees. Wood decay and other conditions predisposing breakage, in a storm or otherwise, isn't always apparent from the tree's exterior. Tree decline can take a surprising amount of time to manifest (months or even years), and the death of a tree from decline can take just as long.
A variety of factors can contribute to tree decline, both natural and human-caused. While we acknowledge that many of the trees you're asking about were likely growing wild rather than planted, if you do opt to install replacements over time to help reforest the land, planting trees in locations that suit their needs in terms of soil, sunlight, and room to mature is the best way to set them up for success to reduce the risk of long-term issues. Planting depth is also very important, which you can learn about in the links below that address both new tree selection and planting as well as established tree decline (focused on oaks, but applicable to other species as well):
For the current trees, if snags remain or if damaged trees can't be addressed with pruning to "clean up" the jagged wood torn by falling limbs, that's okay. As long as they don't damage property or risk harming people when they fall/fail, declining and dead trees are good to keep for the benefit of wildlife. They won't necessarily pose a risk of pathogen infection or insect infestation for any surrounding trees if they are otherwise healthy and minimally stressed.
To help assess tree stress and health, a certified arborist or licensed tree expert can be consulted to perform an on-site evaluation. While they cannot cure or treat every ailment, they can help to make a diagnosis, as well as look for sources of tree stress that might be able to be alleviated. While a few pathogens can attack healthy wood, usually wood decay follows an injury (maybe a lightning strike) that gives the pathogen spores an opening for infection, and wood-boring insects similarly tend to preferentially target trees stressed by drought or over-saturated soil. The excessively heavy rains in 2018 and 2019, and the drought of 2023 (and this year, so far) are likely not helping, even if they weren't the original contributor to decline.
Miri
A variety of factors can contribute to tree decline, both natural and human-caused. While we acknowledge that many of the trees you're asking about were likely growing wild rather than planted, if you do opt to install replacements over time to help reforest the land, planting trees in locations that suit their needs in terms of soil, sunlight, and room to mature is the best way to set them up for success to reduce the risk of long-term issues. Planting depth is also very important, which you can learn about in the links below that address both new tree selection and planting as well as established tree decline (focused on oaks, but applicable to other species as well):
- Why Oak Trees are Declining or Dying
- Browning and Defoliation of White Oaks (oak species can be categorized into the "red oak" or "white oak" groups, since they are more related to each other within the group than between groups)
- Planting a Tree or Shrub (includes a link to our blog article "Free the Flare: Maintain Visible Root Flare for Tree Health")
- Planting Trees in our Changing Climate (includes links to lists of trees predicted to be suitable to certain changes in site conditions, like higher heat and less regular rainfall)
For the current trees, if snags remain or if damaged trees can't be addressed with pruning to "clean up" the jagged wood torn by falling limbs, that's okay. As long as they don't damage property or risk harming people when they fall/fail, declining and dead trees are good to keep for the benefit of wildlife. They won't necessarily pose a risk of pathogen infection or insect infestation for any surrounding trees if they are otherwise healthy and minimally stressed.
To help assess tree stress and health, a certified arborist or licensed tree expert can be consulted to perform an on-site evaluation. While they cannot cure or treat every ailment, they can help to make a diagnosis, as well as look for sources of tree stress that might be able to be alleviated. While a few pathogens can attack healthy wood, usually wood decay follows an injury (maybe a lightning strike) that gives the pathogen spores an opening for infection, and wood-boring insects similarly tend to preferentially target trees stressed by drought or over-saturated soil. The excessively heavy rains in 2018 and 2019, and the drought of 2023 (and this year, so far) are likely not helping, even if they weren't the original contributor to decline.
Miri
