On June 16, 1940, there were published an article in the Estonian newspaper "Postimees" titled "Why do our elms dry?".
This article described the invasive fungal disease - Duch elm disease (DED), (Ophiostoma ulmi - with slower development or more aggressive form Ophiostoma novo-ulmi) - and then it was written: "The disease occurs massively, spreads rapidly, and a large part of our elms is already caught or even destroyed".
History seems to be repeated and Estonia has been hit again by a large variety of outbreaks.
Over the country, you can often encounter sick trees at different stages - in parks, green spaces, gardens, and so on.
What are the symptoms of this fungal disease?
Relatively firmly, you can determine the disease by cutting off the sick branch and looking at its diagonal section when the first signs of the disease appear - if there is a dark streak near that outer edge, you can be quite convinced that this is Dutch elm disease (DED).
Trunk has often open bark (although not at the beginning of the infection), as if the tree were covered with a open coat.
However, no open bark is present on all sick trees, but a dark streak is always present.
How to prevent?
Do not know yet.
What to do?
Basically, we can't do anything for the sick tree.
What can be done is to prevent the spread of the disease.
To do this, it is necessary to constantly monitor the state of the tree, and if it is seen that the signs are spreading fast and the drying of the tree seems to be certain, the tree should be cut.
Is this enough?
No.
The following is important:
1. The tools used for cutting (generally saws) should be disinfected (with antiseptic) after finishing work.
2. Cutting residues - should be burned immediately or -
3. When storing - if you want to make firewood for yourself - the logs should be peeled off and the bark should be burnt immediately (the bark must be peeled because of the bark beetles that spreads the fungal infection).
If you follow these steps, you have already done a lot for other elms.
Source: author's personal notes and observations.
Also consulted by Liina Jürisoo, an Estonian University of Life Sciences doctoral student.
http://ravelreiljan.blogspot.com/
This article described the invasive fungal disease - Duch elm disease (DED), (Ophiostoma ulmi - with slower development or more aggressive form Ophiostoma novo-ulmi) - and then it was written: "The disease occurs massively, spreads rapidly, and a large part of our elms is already caught or even destroyed".
History seems to be repeated and Estonia has been hit again by a large variety of outbreaks.
Over the country, you can often encounter sick trees at different stages - in parks, green spaces, gardens, and so on.
What are the symptoms of this fungal disease?
Typically,
the disease begins with one or more twigs on the tree, with sharp
wilting and drying - whereby the dried and kinky leaves remain on the
tree.
 |
| The first sign of danger - dried branches in the crown. Photo: Ravel Reiljan |
Then,
the whole crown will dry out, which can take younger trees only a few
weeks and older trees from a couple of months to several years.
 |
| Dying elm tree. Photo: Ravel Reiljan |
Finally the whole tree dries and dies.
 |
| Dead elm tree. Photo: Ravel Reiljan |
Relatively firmly, you can determine the disease by cutting off the sick branch and looking at its diagonal section when the first signs of the disease appear - if there is a dark streak near that outer edge, you can be quite convinced that this is Dutch elm disease (DED).
Trunk has often open bark (although not at the beginning of the infection), as if the tree were covered with a open coat.
However, no open bark is present on all sick trees, but a dark streak is always present.
 | ||
| Dark streak is easily visible. Photo: Ravel Reiljan |
Do not know yet.
What to do?
Basically, we can't do anything for the sick tree.
What can be done is to prevent the spread of the disease.
To do this, it is necessary to constantly monitor the state of the tree, and if it is seen that the signs are spreading fast and the drying of the tree seems to be certain, the tree should be cut.
Is this enough?
No.
The following is important:
1. The tools used for cutting (generally saws) should be disinfected (with antiseptic) after finishing work.
2. Cutting residues - should be burned immediately or -
3. When storing - if you want to make firewood for yourself - the logs should be peeled off and the bark should be burnt immediately (the bark must be peeled because of the bark beetles that spreads the fungal infection).
If you follow these steps, you have already done a lot for other elms.
Source: author's personal notes and observations.
Also consulted by Liina Jürisoo, an Estonian University of Life Sciences doctoral student.
http://ravelreiljan.blogspot.com/
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