Dutch Elm disease is a terrible disease condition that affects trees.
This is mainly caused or spread by the elm bark beetle, which carries and spreads an invasive fungal pathogen, the Ophiostoma Novo-ulmi.
The Dutch elm fungus spreads to the tree as the bark beetle feeds.
As a tree gets infected, a gradual but steady spread of the disease across the tree and to other trees occurs. Tree-to-tree spread of this disease happens via root grafts.
This gives rise to several symptoms that may worsen if urgent attention isn’t given to addressing the problem.
Symptoms of Dutch Elm Disease
A lot of times, knowledge of three infections or diseases are only evident after symptoms begin to show.
Here, activities of the elm bark beetle may not be noticed at all or may be seen when it’s too late. Knowing what to look for gives you an idea of when to act.
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Primary symptoms of Dutch elm disease include galleries, defoliation, dark streaks in branches, and branch dieback. The longer these symptoms are left unattended, the worse it gets.
Let’s learn more about these symptoms before getting into details on how to treat the disease.
i. Galleries
When elm bark beetles infest, their feeding activity leads to the creation of galleries.
The same applies to their larvae. These pests do an excellent job of hiding their activity by feeding beneath the bark, which is why you won’t readily notice their presence.
During checks or examinations, lifting the bark will reveal a network of galleries that appear as lines and connect to a deep center line.
When this is found, it’s a clear sign of trouble and the need to have it treated.
ii. Shedding of Leaves
There are times or seasons when leaves lose or shed their leaves which is a natural process.
However, when shedding or defoliating leaves seems unnatural, it’s a sign of a problem due to Dutch elm disease.
Here, leaves begin to wilt, discolor, fade & curl, then fall off.
This is primarily due to the absence of water and nutrients from the disruption caused by elm bark beetles to the normal functioning of trees.
Nutrients and moisture taken up by roots are unable to reach the leaves.
iii. Dark Streaks in Branches
If you aren’t too sure about the causes of unnatural leaf shedding, you may want to check for dark streaks in branches.
Here, bark from branches must be removed to see if there are dark streaks in the sapwood underneath the bark. If you spot these, it’s a vital sign of Dutch elm disease.
While this is a helpful way to ascertain the problem, it may not be enough to tell exactly what the problem is. You may need to call for professional testing.
Here, the dark streaks are tested, and the exact problem is identified.
iv. Branch Dieback
Branch dieback is a condition that happens to trees infected by the Dutch elm disease.
While that is true, other diseases also cause similar symptoms. This knowledge makes it necessary to probe further to determine the problem.
The other steps or symptoms mentioned going a long way in helping you figure out the actual problem with your tree.
With all these symptoms showing, it’s a clear sign your tree is infected and needs urgent intervention. Sometimes, intervention may require obliterating the tree.
Who to Call for Dutch Elm Disease Treatment
When Dutch elm disease is confirmed, you’ll need to take immediate steps to fix the problem.
While that is important, not everyone is trained in handling such situations. If you venture out to perform treatments, you may make a mess of the case.
This may worsen the condition of the tree.
A professional arborist or a tree service should be called to inspect and offer solutions to the problem. These are trained technicians skilled and experienced in all kinds of tree diseases and conditions.
The results from their assessments will determine the recommendations given.
Treating Dutch Elm Disease
When it comes to Dutch elm diseases, a proactive approach to treatment tends to be the most effective. In other words, treatment must be made before this disease ever gets to your tree(s).
The reason for this is simple; Dutch elm disease can rapidly spread through a tree, thus making catch-up treatment almost impossible.
In a nutshell, a preventive approach is needed to treat this condition. While there are multiple approaches to such treatment, a Propizol fungicide injection administered to the trunk helps safeguard the tree.
This can either be given before the disease gets to the tree or at its earliest stage.
Giving this injection after the disease is full-blow will have no effect whatsoever. Injecting the tree trunk is just one of several actions to take.
Others include stripping off bark from branches showing flagging symptoms. This should be followed by immediate pruning of the flagging branches.
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More Treatment Approaches
Additional steps to take include a close inspection of sapwood for dark staining.
Now the branch will need to be cut to the branch bark collar. Proper disposal of infected limbs and bark is highly essential. Tools used during the procedure are likely to be infected too.
Have them disinfected using a bleach solution and frequently between each drill and cut.
Now to the hard work of preventing or slowing down further spread to nearby trees, you’ll need to have a trench dug. For many, this strategy wouldn’t be suitable as it’s invasive.
When treatment is performed by a professional, the process is much more comprehensive. You won’t have to worry or be pressured regarding how to fix the problem.
Tree removal may be recommended for situations where the disease has spread significantly.
When it’s not too late to Treat
Dutch elm disease can significantly impact a tree when left unattended.
As stated earlier, the best treatment for this condition is by taking a proactive approach. Another option is to have your tree injected with Propizol when less than 15% of the tree’s canopy is affected.
Dutch elm disease treatment is a necessary procedure that needs to be carried out quickly to prevent the rapid spread of the disease. When not promptly acted on, the tree is unlikely to recover.