Arborvitae are one of the most popular plant choices here in Louisville and beyond. They are fast-growing, can be used in a variety of applications, and overall a low maintenance plant choice.
But that’s not to say there are zero arborvitae problems.
As with any plant in your landscape, there are some potential problems that can affect the arborvitae.
In this article, we’ll dive into some of those specific issues so that you can have a better grasp on caring for arborvitae trees.
Like other plants in your landscape, your arborvitaes can be subject to potential pest problems. Here are a few to keep on your radar.
Bagworms are one pest that happens to be fond of the arborvitae. These larvae actually make their bags out of needles, making them difficult to spot amongst the branches.
However, as those needles turn brown, the bags will start to stand out. Unfortunately, at this point, the bagworms have likely already spent quite a bit of time chewing on your plants.
To get rid of bagworms, you can hand pick or cut the bags from the infested plants before they hatch. However, this only works if you have a small problem. If your arborvitae is infested, it might be difficult to be certain that you’ve removed all of the bags. Professional product applications during and after bagworm larvae hatch is recommended.
Another common arborvitae pest is the spider mite. Trees and shrubs can have good mites and bad mites. The “good mites” are those that are beneficial to the tree because they eat bad mites, like Spider Mites. Spider Mites are aggressive tree bugs that cause a lot of damage by sucking the cell content out of needles. They are tiny but highly destructive.
Due to their small size, they are difficult to detect. You may start to notice your arborvitae’s needles are turning yellow (or brown) before you ever spot the actual mites. Mites can also leave very small webbing within needles.
The most effective treatment option for mites is a selective program that maintains the beneficial mites while killing the bad ones.
Scale is another problem on arborvitae plants. Scale insects are a group of sap-feeding pests that use their piercing-sucking mouthparts to drain fluids from your plants. Fletcher scale is the most common variety found on arborvitae.
Signs that your arborvitae might have scale is yellowing of the needles or the presence of a sticky substance called honeydew. This is left behind as scale feed. Sometimes the honeydew attracts other pests like flies and bees so an increase in pest activity is also a sign.
Arborvitae problems can also be related to disease. Just like other plants in your landscape, arborvitae plants can struggle with disease. Here are some of the common arborvitae diseases that we see.
Root Rot is a general term for any disease with a pathogen that attacks the roots of trees. It’s usually a result of oversaturated soil. The impact of Root Rot is initially seen at the soil level with symptoms like mushroom growth or the roots appearing wet. Soil might also appear soggy and fail to drain.
But Root Rot will eventually lead to symptoms in other areas of the tree like yellowing or wilted leaves. After all, a tree needs its roots for optimal health and survival.
This is a fungal disease affecting the needles and the shoots of arborvitae. When arborvitaes are infected with blight, the needles generally turn a pale green or yellow color. This disease can cause major problems if repeated infections occur over time. Eventually, it could lead to the death of your arborvitae.
Pruning away diseased sections and following good cultural habits (like proper watering and mulching) can help prevent blight from spreading. Sometimes fungicides are also applied.
When an arborvitae has Needle Cast, its needles will turn yellow, then brown, and eventually fall off. Of course, there are other tree problems that can lead to this as well. Problems with over or underwatering can also cause needles to change colors.
Needle Cast is also mistakenly diagnosed as spider mite damage as it does present similarly. But spider mites typically cause needles to turn more tan than brown. You might also notice with Needle Cast disease that there is some black fungal growth.
Of course, diseases and pests are just two potential categories of arborvitae problems.
Other potential problems could be related to improper planting, too much (or too little) water, winter burn, sun scorch, or even a soil contaminant. Just like the other plants in your landscape, your arborvitae can be subject to some harsh weather or environmental conditions that can lead to issues.
Sometimes it could be a matter of improper care of your arborvitae. As we mentioned, both under-watering and overwatering can pose problems. Believe it or not, it’s often more common for us to find arborvitae are overwatered. If the soil is compacted, it can easily get waterlogged and the roots can drown or rot.
Malnutrition is another potential issue. Your arborvitae might not be receiving ample nutrition, particularly if you have some soil issues. Sometimes this can be fixed with a fertilization service.
If your arborvitae are turning yellow or brown, losing needles, or experiencing some sort of other sign of trouble, it’s important to talk to a plant health care expert who can help you diagnose what’s going on.
Correcting arborvitae problems first begins with making a proper diagnosis.
Unfortunately, sometimes there is no solution. If the problem comes down to the fact that your arborvitae was planted in a poor location for its needs, it may never thrive. In the end, it might be best for you to replace the plant with something more suitable to the conditions. It’s important to work with a plant health care expert who will be honest and transparent with you when it comes to this sort of information.
At the end of the day, you just want to feel confident that your trees and shrubs can deal with whatever is thrown at them. There are many potential stressors in the landscape that can really cause problems for your arborvitae (as well as your other plants).
The last thing that you want is to lose any of your beloved landscaping to a problem that could have been prevented or treated.
This is why it is so valuable to partner with a plant health care professional.
As you do that research on pros in the area, we’d love for you to consider Limbwalker. Not only can we help diagnose tree problems but we can also implement the proper solutions and help you prevent many problems in the first place.
If you’d like to learn more about tree services for your Louisville home, get in touch, get your quote, and get back to enjoying your yard.