Like most tree species, elm trees are affected by a number of disease conditions which take a toll on the health of the tree. Elm tree diseases are under focus here. In this article, we discuss what these are about, common symptoms, treatment for such conditions as well as preventive approaches or treatments.
If you discover an abnormal condition showing on your trees, you might want to find out what exactly it is. Also, knowing what actions to take and who to approach for treatment is paramount. As you read this article, you’ll find all the information you need to identify and tree elm tree diseases.
About Elm Trees
While we aren’t focused specifically on elm trees, it’s necessary to provide some background information. These are large shade trees with serrated and circular leaves. They’re mostly known to be deciduous and semi-deciduous.
Wood from this tree tends to be durable and strong while also being resistant to rot and weather. Their stately appearance has made them one of the most planted shade trees across the country. However, diseases, especially the Dutch elm disease is known to have killed millions.
When it comes to diseases affecting the elm tree, there are several of them. Some of these diseases tend to be more severe and debilitating than others. Now there’s no way to identify such diseases without knowing about the symptoms. In this section, we take a look at these diseases as well as accompanying symptoms.
Also included is information on effective treatment methods for the respective diseases mentioned. Popular elm tree diseases include the Dutch elm, botryodiplodia canker, black leaf rot, elm yellows, and laetiporous root rot. Let’s find out further what each of these diseases are.
i. Dutch Elm Disease
The Dutch elm disease is caused by fungi with two main species known as Ophiostoma novo-ulmi, and Ophiostoma ulmi being the main culprits. The target for these fungi is the tree’s vascular system. Most Dutch elm tree diseases spread are done through one of two ways;
The connected root systems of these trees can spread these from one tree to the next. Secondly, adult beetles are known to be responsible for spreading this disease through their reproductive behavior. Elm trees with this condition show a number of symptoms.
Such symptoms include branch death, premature leaf drop, leaf wilting and as well as leaf discoloration (turning yellowish and brownish). You’ll also notice wilt spreading fast in an inwards fashion (that is towards the tree’s trunk).
When a cross section of a dying limb is cut, it’s observed to have brown streaking in sapwood. All or any of these conditions will require urgent action to fix the problem. A number of measures can help to fix the problem.
When elm trees are discovered to have this disease, steps need to be taken to prevent further spread. One of such preventive action includes seasonal application or injection of fungicides.
Pruning action is one of the primary actions taken when elm tree disease is noticed. While this will help, it’s best performed on elm trees with newly infected crowns. To have a real chance of containing it, consider calling an arborist for your pruning needs.
Use of Insecticides
Insecticide use is another way Dutch elm tree disease can be stopped. This method mainly targets the beetles responsible for creating the favorable conditions needed for the emergence of fungi.
Disconnecting Root Grafts
We mentioned that Dutch elm diseases can be spread via the root network of trees. Trees within close proximity (within 25 to 50 ft. of each other) are likely to spread this disease faster. A professional arborist helps disconnect these grafts or connections to prevent further spread.
ii. Elm Yellows
Another elm tree disease you may notice is elm yellows. As the name implies, one of the conditions you’ll notice is a yellowing of the crown which also tends to droop. Elm yellows disease is quite aggressive and spread through leafhoppers and root grafts.
Unfortunately, elm yellows disease has no known cure. It is caused by phytoplasmas known to infect the inner bark section of trees. What results is damage and death of the tree’s phloem, thus preventing the flow of nutrients and water.
Identifying this disease requires knowing what the symptoms are. Common symptoms of elm yellows include leaf drops, yellowing and drooping of crown, death of branches, dying of root hairs, discoloration of inner bark tissues, and killing of the phloem. You’ll need to call a pro for detailed inspection.
We’ve stated that this disease has no cure. This leaves you with few options to prevent further spread to other trees. The following actions can be taken to keep other elm trees safe.
Use of Antifungal Sprays
Antifungal spray comes handy when seeking to kill off fungi that could spread this condition. Here, the locations where infected trees previously were are treated. Of course such trees need to be removed for that to be possible.
Removal and Destruction of Tree
Because elm yellows have no cure, affected trees need to be removed and destroyed. You’ll need this task to be professionally done. An arborist knows exactly what to do. It’s best to follow expert advice during removal and destruction of affected trees.
Comprehensive Removal of Roots
When elm yellow disease infects your tree(s), it goes beyond the trunk to the root system. Here, not only is the tree removed, its roots need to be removed as well. A thorough job is needed to help get rid of the disease.
Insects targeting the phloem of are likely to be around when affected elm trees are being removed. To get rid of them, topical application of pesticides is needed to kill these bugs.
Always Hire a Pro
When it comes to elm tree diseases or any other, you’ll need to be extra careful with how the treatment process is executed. Your best bet to having a lasting solution is by calling the pros.
These are some elm tree diseases worth knowing. We’ve included the symptoms and treatment approaches used. Whichever disease you encounter, it’s best to call for professional help.