There was a time when American Elm was liked and considered the best. It was fast-growing and long-living, but soon the Dutch Elm began affecting the Elm population. The losses to the trees are worse, and many of the experts are on a mission to save the trees, and those which cannot be saved, the replacement has to be found.
What is Dutch Elm disease?
Dutch Elm is a disease that affects the elm trees. Some of the trees that have it cannot be saved. It is a member of Sac fungi and is spread by bark beetles. It can be found in America, Europe, and has also reached New Zealand. Even though it originated in Asia, but it has devastated many native populations of the Elm trees in other continents. The name comes from its identification by Dutch phytopathologists Bea Schwarz and Christine Buisman who both worked with Professor Johanna Westerdijk. It was identified in 1921.
How to Identify it?
Certain ways can help you with identifying it. You have to look out for the symptoms. The symptoms will spread to the branches first. This is where you can spot it. It will move on from branches, and eventually, cover the whole tree, and finally killing it. The symptoms include Leaves turn yellow, and then brown, Premature leaf drop, branch death, and Brown steaking of sapwood. The process can happen in a season, or take years to fully kill the Elm tree
No Elm tree is immune to the disease. American tree is more vulnerable to DED, while as European and Asian are more powerful. There is no immunity, so you have to bear it in mind, that all Elm trees can be infected.
You must catch the disease early if you want it to work. You have to prune the wood out of the trees and destroy it. The best is to pair it with the fungicide. However, if the whole tree is infected, the situation becomes more urgent. Remove the tree before it infects others.
Breaking the connection:
If the tree is infected, and there is nothing left to save, the least you can do is to remove the tree, but also keep in mind that the roots of it could be connected to the other trees. Use the proper machinery to break the root grafts before the infected tree is removed
Insecticides can be useful to kill the bark beetles that cause the spread. They can be effective, but there is no surety.
This is done by a professional. The fungicides are injected into the tree to kill the bark beetles that spread the disease. This is a thorough process and needs to be done properly.
You have to look out for the early symptoms. If one tree is infected, it doesn’t mean that the others have to be. Remove the tree before it infects others.