Abundant Tree Team

Marion Tree Care: More on Managing Disease in May

We are continuing our focus on fighting those pesky diseases for the month of May. We’ve covered two of the biggest tree care threats: Dutch Elm Disease and Emerald Ash Borer. Now, we will highlight a few more enemies of the arborist and tree fan. We believe it’s important to stay ahead and on top of these pests in the fight to save our trees.

Fire Blight

This one gets its name from the scorched appearance of infected leaves, stems, and bark. It mainly affects apple and pear trees, attacking their blossoms in early spring and then moving up through the twigs and branches. You’ll notice blossoms turning brown, wilting, and dying in just about 1-2 weeks after infection. You might also see an amber-colored ooze coming from the bark (Gross, right?).

Fight it by performing a comprehensive cleanup around your trees when fall rolls around. Move all debris, fruit, and fallen leaves away from the tree and destroy them to prevent the bacteria from spreading. Fertilizers can be helpful but you’ll first want to perform a soil test, or simply contact your local tree care professional to make sure it’s properly selected and applied. Prune any infected branches and be sure to sterilize your pruning tools. Fight fire with fire when possible by burning and destroying affected limbs.

Forest Tent Caterpillar

Small but deadly, the forest tent caterpillar’s larvae are voracious eaters. Their favorite feast involves sugar maples and poplars but they’ll also happily infect oaks, water tupelo and sweetgum in the coastal south, red alder and willow in the Northwest. They are known to defoliate extensive areas. These creepy crawlers produce one generation a year, appearing when leaves begin to unfold. The freshly hatched larvae will be black, hairy, and move in groups on twigs and the trunk. The destruction they leave behind includes a stripping of foliage from mid-Spring to early summer.

Fight it by using sprays and barriers; there are a variety available. Call us if you suspect your trees are under the influence.

Powdery Mildew

This one is an easy one to recognize as it appears as a white or gray powdery growth on leaves. Thankfully, it is usually not lethal but it can disfigure and limit the productivity of your plants and trees.

Fight it by planting in sunny sites, trimming inner branches in order to increase air circulation and limit the use of fertilizer. If the mildew has already claimed its place, prune and discard diseased portions and apply fungicide to the remaining leaves.


Athracnose is actually a general term for a variety of fungal diseases that affect plants in similar ways. They typically cause dark sunken lesions on leaves, stems, flowers, and fruits, and can spread very quickly during rainy seasons.

Fight it by immediately removing and destroying any infected plants in your garden. When it comes to trees, prune out dead wood and destroy infected leaves. Certain fungicides can be utilized but we recommend having a professional out to help you choose the right one.

Again, if you notice any of these signs, don’t wait to call your local arborist. Some skillful tree pruning could slow down or even kill the progression of the disease. Even better, prevent the infestation from happening at all.  Abundant Tree Care Marion will come over and inject the proper pesticide or fungicide into the tree, providing excellent protection against these threats. In the unfortunate case that the damage is done, we’d be happy to come over and see if tree removal is necessary.