Kentucky's forests consist of two main types: oak/hickory and oak/pine. Various species of hardwoods are very common, such as cherry, hickory, maple, oak, walnut, and yellow-poplar. However, there are some areas of pine forests as well, including eastern white, loblolly, pitch, and Virginia pine species.
A glossy privet bloom with its small white flowers and thin green stems.
Flowers from a glossy privet, an invasive plant species
The most severe threats to our forests are:
Insects
Invasive plants
Diseases
Extreme weather
This page covers the most influential of these threats and their recent impacts on the Commonwealth of Kentucky.
If you have questions or need assistance with forest health, don't hesitate to reach out! Find your county on the map below to discover your branch office location and its contact information.
Kentucky Division of Forestry color coded counties by branch assigned field office (star) and tree nurseries (point).
Invasive Pests and Plants
A big threat to the health of our forests is invasive species. These can come in the form of animals (such as insects) or plants. Invasive species are often not native to their new habitat, and can be spread there by humans or other factors. These species have few to no natural predators, allowing their populations to grow and disrupt entire ecosystems.
The emerald ash borer(EAB) is an exotic invasive pest that feeds on ash trees in its larval state. The damage it causes leads to the death of the trees. This green beetle was first established in Kentucky in 2009 in the eastern part of the state. It has since spread westward and now inhabits 103 counties. The Kentucky Division of Forestry (KDF) has recently been approved to release a species of wasps in infested areas. These wasps lay their eggs inside EAB eggs.
Check out this treatment guide if you think you have some on your property!
An adult emerald ash borer on a leaf. It has a thin green body and the green leaves in the image have water droplets on them.
An adult EAB
Another exotic invasive species, the hemlock woolly adelgid (HWA), damages and kills eastern hemlock trees by draining them of their sap. It was established in Kentucky in 2006. The KDF has been working since 2009 to treat hemlock trees using insecticide, better protecting them from the pest. The KDF has also recently begun releasing natural predators of the HWA, two species of beetles, to establish their populations.
Is this pest causing damage to your trees? Check out this treatment guide!
A hemlock tree infested with hemlock woolly adelgid. The tree has pine-like needles and there are small wool-like white balls along the twigs of the tree, which are HWA.
A hemlock tree infested with HWA (the small white "balls of wool")
The spongy moth, previously known as the gypsy moth, is extremely destructive to oak species in its caterpillar stage. It's known as a defoliator, which means that it consumes leaves from oak plants. While this pest hasn't been established in Kentucky, it has been caught in traps since surveys began in 2005. Most recently, in 2023, 105 moths were found in traps across 29 counties.
A spongy moth caterpillar on the stem of a plant. The caterpillar has strands of long, spiky hair (some black, some yellow) and somewhat of a striped pattern. This pattern is blue and gray on the front part of its body and orange and gray on the back part. There's some yellow coloring around the stripes.
The spongy moth in its caterpillar stage
The spotted lanternfly is not a fly but a hemipteran. This is a type of insect that has a mouthpart designed for sucking nutrients out of food sources. These pests feed on tree of heaven, red maple, black walnut, and other fruit trees and grape vines. While they don't cause the death of these plants, they do make them more vulnerable to stress and disease. This pest has been established in only two of Kentucky's counties, Gallatin county and Boone county.
A spotted lanternfly on a tree of heaven. There's a green growth on the bark of the tree, and the insect has long black legs, a small head, and pinkish-colored folded wings. The wings are spotted with black most of the way down and are thinly striped with black the rest of the way down.
A spotted lanternfly on a tree of heaven
An invasive plant that you might have seen before is the bush honeysuckle. This species is fast-growing and can easily claim other plants' habitats as its own. Known for its sweet smell and white and yellow flowers, this plant is sometimes bought for aesthetic purposes. Unfortunately, this allows it to spread faster and cause more harm to native species.
One way to protect against this damage is to buy a native alternative to bush honeysuckle, such as thetrumpet honeysuckle. This helps protect other native plants while also meeting aesthetic needs.
Two foresters removing bush honeysuckle in a forest overrun with it. They're both wearing long sleeves and pants, gloves, protective eyewear, and boots. One is bent down examining a large bush honeysuckle while the other is holding several bush honeysuckles that have already been removed.
A member of the Friends of Big Bone Lick volunteer group and a KDF Forest Ranger Technician working on bush honeysuckle removal at Big Bone Lick State Historic Site
Learn more about bush honeysuckle by watching this video, brought to you by Alexandra Blevins and Kenna Smith from the Kentucky Division of Forestry Forest Health Program.
A patch of tree of heaven. Several pale thin trunks are visible, while most of the image shows the leaves of the plant. They're long and thin, most of them green while some are yellow or a very light red.
A patch of tree of heaven
Another invasive plant found in Kentucky is tree of heaven, one of the spotted lanternfly's favorite food sources. It was introduced to the United States centuries ago because of its beauty, but is able to reproduce quickly and survive in many conditions. This has caused it to become a big issue for Kentucky's natural flora.
Choosing to buy a native alternative such as sassafras, red buckeye, or American holly instead of tree of heaven is a great way to keep it from spreading. This also lets Kentucky's native plant species thrive.
A large group of Callery (Bradford) pear trees. They're starting to bloom with small white flowers but appear somewhat bare.
A group of Callery (Bradford) pear trees
Another invasive plant that's cause for concern is the Callery (Bradford) pear. This tree arrived in the United States over a century ago and used to be unable to reproduce. However, they recently began to grow small fruits, which caused the population to rise as birds spread the seeds.
The Callery (Bradford) pear is known for its smelly white flowers, which are soon followed by bright red foliage. Thankfully, there are many native alternatives to this plant, such as dogwood and serviceberry. Planting these alternatives is much healthier for Kentucky's forests.
If you'd like help with planting trees in your community, visit this page from the Kentucky Division of Forestry's Urban and Community Forestry Program.
Harmful Diseases
Another factor affecting forest health is the presence of diseases. There are many that can be spread from tree to tree by insects known as vectors. These diseases can be hard to identify, but this document explains how to spot certain diseases in specific tree species. Two of the diseases the KDF is most concerned with are known as thousand cankers disease and laurel wilt disease.
Thousand cankers disease (TCD) is a fungal pathogen carried by the walnut twig beetle. This beetle passes it to eastern black walnut trees when it burrows into the bark. The disease is identified by spots known as cankers that discolor the wood. Ground surveys and trapping efforts have helped keep this disease out of Kentucky. However, it's been established in some eastern states including the neighboring states of Indiana, Ohio, Tennessee, and Virginia.
A tree branch or trunk on a flat surface with some of the bark scraped off. The wood under it is a pale yellow tinged with green, and there are four dark spots among it (Thousand cankers disease). They have thin dark rings around their edges and dark spots at their centers, with the space in between being a darker yellow than the wood. All four spots have tiny holes in the middle.
An example of what TCD looks like
Laurel wilt disease (LWD) is new to Kentucky, having just been established in 2019. This fungal pathogen is spread to sassafras trees and spicebush by the redbay ambrosia beetle, which bores into the wood. The range of this disease implies that its vector has traveled along interstates (see map). The KDF is working with the University of Kentucky and Bartlett Tree Experts to determine which fungicides will best protect the plants from this disease.
The trunk of a sassafras tree with the bark cut away. The first layer of wood underneath is orange, which gives way to very pale wood which then gives way to a layer of wood streaked with dark lines (laurel wilt disease).
A sassafras tree with LWD, made clear by the dark streaks present in the wood
A "save your sassafras" PSA from the KDF. It's typed out on a green scroll-like background with leaf graphics in the corners and reads: Do you want to be part of a new forest health project that could help save thousands of trees? There is promising research that shows certain fungicides can help stop the spread of the lethal fungus and protect healthy trees from LWD, but more field trials are needed. The University of Kentucky, in partnership with the Kentucky Division of Forestry and Bartlett Tree Experts, is looking for landowners willing to participate in a series of fungicide trials to protect our native sassafras trees from LWD. The results will greatly improve our knowledge of how to combat this disease, help save trees throughout Kentucky, and influence the science and treatment options related to LWD for many years to come. You are eligible to participate in the trials if you live in any of the positive detection counties. If you're concerned about your sassafras, but don't want to participate in the trials, anyone can treat their trees! Please reach out for more information on how you can do this and for opportunities to get involved with our citizen science program. INTERESTED? email Alexandra.Blevins@ky.gov or call 502-382-1720
Save your sassafras PSA from the KDF
Check out this video to learn more about laurel wilt disease and how to identify it in sassafras trees.
A set of pine needles on a flat surface. The needles are green at the base but turn brown as they go out, with the ends being a light color and seeming dried out. The brown parts of the needles are patterned with lighter and darker tones.
Loblolly pine needles infected with brown spot needle blight
Also, Brown spot needle blighthas recently been affecting some of Kentucky's pine trees. This fungal disease was observed in loblolly and eastern white pine in Central and Eastern Kentucky, respectively. The University of Kentucky plant disease diagnostic lab confirmed its presence in both Edmonson and Pike counties.
For loblolly pines, this disease causes discoloration in the needles, striping them with brown and drying them out. Eastern white pines don't experience the same browning effect, but the needles still discolor and drop.
While this disease isn't a top priority of the KDF, brown spot needle blight is still observed since it affects the health of our forests.
Severe Weather
Kentucky has faced many severe weather events in the past few years including ice storms, tornadoes, drought, and wildfires. These have all had distinct effects on forest health.
A tree affected by ice storms. The tree is thin and bent to the point where the top branches are brushing the ground, which is dusted in snow. A snow-dusted field is in the background.
An aerial view of a forest affected by ice storms. Several trees are lying on the ground and others seem to be coated in ice, the rest appearing green from above.
An aerial view of a forest affected by flooding. A messy river of tan-colored water weaves around a forest of trees, many of which are standing in the flood.
A forest surrounding a flood of brown, murky water which seems to be blocking a path. Several trees are sitting in the water.
Trees and forests affected by ice storms (top) and flooding (bottom)
Three back-to-back ice storms hit the state in February 2021. They brought with them enough ice to snap branches and uproot trees. The most severe damage took place in Eastern Kentucky. Heavy rain arrived just two weeks later. This caused the largest flash flooding event that had ever been documented in state records. Severe storms also led to devastating floods in July of 2022, resulting in damage and destruction in Kentucky's Appalachian region.
Dozens of foresters were deployed after these events to help with recovery efforts. These KDF employees used saws to cut up broken branches and downed trees, clearing debris.
Tree damage caused by the December 2021 tornadoes. The bottom half of an uprooted tree is lying on the ground and another tree with a split trunk is forming a 90 degree angle over it. Several other trees are missing their tops and the ground is covered in debris.
December 2021 tornado damage
In 2021, a massive storm swept through Kentucky on December 10th and 11th. It brought with it 7 tornadoesthat touched down a total of 21 times. It also included a long track supercell that covered over 150 miles of ground in Kentucky and reached wind speeds as high as 190 mph.
KDF employees were sent to help with rescue and recovery during the emergency. They moved debris out of the way of first responders.
Most of the damage fell in the Western and Central regions of the state, with over 7,300 acres of timber damage being recorded. In some locations, a stark change in canopy cover was observed after the storms (see images below).
Two aerial views of the same part of a forest outside Dawson Springs, KY that show the change in tree cover before and after the December 2021 tornadoes. Many trees are downed in the 2022 picture, while the trees in the 2020 picture appear healthy.
Tree cover in 2020 (left) and 2022 (right) outside Dawson Springs, KY, a city heavily impacted by the December 2021 tornadoes.
In the late fall of both 2022 and 2023, Kentucky experienced drought conditions and wildfires. This weather affected Western Kentucky the most in 2022 and Eastern Kentucky the most in 2023.
A man in a firefighter hat and protective clothing using a chainsaw on tree remains in a forest. Sticks and white ash are on the ground and the trees have a sparse amount of orange leaves.
A wildfire at night. The fire line is a bright orange and cuts through the image, leaving part of it dark and the other part glowing orange with flames. Smoke reflecting this glow rises above.
James Baunach from the Campbellsville Branch helping with recovery efforts (left) and the 2023 Feb Fork fire (right)
To combat the damage being done, the KDF entered mobilization to prioritize the situation. The term mobilization refers to "[t]he processes and procedures for activating, assembling, and transporting resources that have been requested to respond to or support an incident." (Definition from NIMSIC). Out-of-state resources were requested to help control the spread of the wildfires in both years.
The 2023 fires did much more damage than those from 2022, the former having a total of 269 wildfires that burned around 34,500 acres. This led to a State of Emergency in the Eastern part of the state.
Interested in how the KDF helps manage wildfires? check out this page for more information.
What Happens Now?
Our commonwealth's forests have experienced everything from invasive pests to severe weather. The work the KDF does for our trees protects these forests as thriving resources for years to come.
There's always more learning and exploring to do when it comes to our forests. Be sure to look at the resources included below!
Spring beauty flowers as they begin to bloom. There are four flowers with pale white petals. Two are blooming while the other two haven't opened up yet. There are green leaves and other plants in the frame.
A locust leaf miner on a plant, which is speckled with light brown and pale spots. The insect is on one of the leaves and has a small black head with a brown body and folded wings. Its antennae and legs are black.
A forester measuring a tree. She's standing in a forest and has a thin, yellow tape measure wrapped around the trunk of a thin tree. The trunk is slanted and runs through the photo diagonally.
Spring beauty flowers as they begin to bloom (left), the locust leaf miner, a native invasive pest (middle), and a forester measuring a tree to determine diameter (right)
Would you like to develop a forest management plan for the trees on your property? If so, check out this link to learn more about how the KDF helps landowners like you.
To view our most recent Forest Health Highlights document, follow this link. It goes into more depth on some of the pests, diseases, and weather affecting our forests.
A graphic of a logo for the Kentucky Division of Forestry, which includes a blue silhouette of Kentucky and a thin horizontal bar that shifts from blue to green. It reads: Team Kentucky Energy and Environment Cabinet Division of Forestry
Contact Information
Kentucky Division of Forestry
University of Kentucky Forestry Extension
USDA Forest Service
Alexandra Blevins
Sower Complex
300 Sower Boulevard-4th Floor SE
Frankfort, KY 40601
http://forestry.ky.gov
(502) 564-4496
Thomas Poe Cooper Building
730 Rose Street
Lexington, KY 40546
forestry.extension@uky.edu
(859)-257-7597
Southern Region, State & Private Forestry
Forest Health Protection
200 W. T. Weaver Road
Asheville, North Carolina 28804
(828)-257-4320
http://www.fs.fed.us/r8/foresthealth/
KDF Forest Health Program Coordinator
Alexandra.Blevins@ky.gov
(502) 382-1720
Flowers from a glossy privet, an invasive plant species
A member of the Friends of Big Bone Lick volunteer group and a KDF Forest Ranger Technician working on bush honeysuckle removal at Big Bone Lick State Historic Site
A patch of tree of heaven
A group of Callery (Bradford) pear trees
Save your sassafras PSA from the KDF
Loblolly pine needles infected with brown spot needle blight
December 2021 tornado damage
Tree cover in 2020 (left) and 2022 (right) outside Dawson Springs, KY, a city heavily impacted by the December 2021 tornadoes.
An adult EAB
A hemlock tree infested with HWA (the small white "balls of wool")
The spongy moth in its caterpillar stage
A spotted lanternfly on a tree of heaven
An example of what TCD looks like
A sassafras tree with LWD, made clear by the dark streaks present in the wood
