Chestnut tree sick?
There is a solution!

The TreeHold Method® is a patented thermal treatment and eliminates pathogenic bacteria by briefly heating them. The trunk and any large branches are completely or partially covered with infrared panels. The radiant heat reaches the sap flow system (the cambium) in a short time, rendering the pathogenic Pseudomonas Syringae bacteria harmless. The total treatment time obviously depends on the size of the tree, but is usually no longer than 4 hours.

Alternative method, based on the same heat principle, uses a less efficient technique and has a treatment time of 48 hours. Due to the high costs, this method is no longer used. Alternatives that are based on other principles (for example: injecting the cambium with a herbal extract) currently have no scientific evidence and are hardly applied.

The TreeHold method can be used by the green companies and green providers of municipalities themselves. The set is for sale or can be rented. After a short training, employees can easily get started themselves. Of course, treatment can also be outsourced to one of the affiliated gardeners. 

The costs for treatment depend on: (1) the size of the tree, (2) the location and accessibility of the tree and (3) the number of trees treated at the same time. Labor costs are the most important factor. Simple calculation examples (no rights can be derived from them), where we assume a tree with a trunk circumference of 3 meters and a trunk height of 3 meters.

• Suppose a municipality has 1 TreeHold treatment set and treats 24 trees per year (on average 2 per month). In that case, the share of the treatment set in the total cost price is slightly less than EUR 100 per tree;
• if the treatment of one tree is outsourced to a certified gardener or to Bomenconservation Nederland, the costs are on average EUR 850 per tree (excluding VAT);
• If several trees are treated at the same time (grouped in an avenue or park and a maximum of 5 per generator), the price per tree will of course decrease considerably.

NB: the costs of not treating a chestnut tree and allowing it to die far exceed the treatment costs. In addition to the costs of felling (including removal of underground parts), in many cases a new tree will be planned. Depending on the location in the built-up area, costs can amount to up to EUR 5.000 per tree!

If desired, a biopsy from the cambium can be analyzed before and after treatment by Wageningen University or another independent laboratory. Lead time depends on laboratory capacity and is on average 2 months. The result is reported to the client.

A visible result obviously depends on the overall condition of the tree and the growing location, but can be expected after approximately 12 months.

Every tree can be treated! However: TreeHold does not recommend treatment if the chance of recovery is estimated to be very low. This is possible, for example, because the tree has been weakened too much, there are acute safety issues or the growing area cannot be improved sufficiently and recovery is virtually impossible.

The method certainly works for almost any form of bleeding disorder, caused by a bacteria or fungus. Field research is currently being conducted into the practical feasibility in Kiwi trees, but also European avenue trees other than the Chestnut. Follow us on socials for the results.

In some cases that is indeed the best option. If secondary pathogens are present, especially the Tonder fungus, felling is often the only safe option. However, the trees affected by the Chestnut Bleeding Disease are not necessarily written off. In almost most cases, digging is not necessary and… ecologically and financially also very unwise.

The bleeding in chestnuts is caused by infection with the bacterium Pseudomonas syringae pv aesculi. (source: Wageningen University).