Weeping Cherry Tree Looks Sick?

Your tree is damaged by a very common disease called tree canker. Very often it is due to a fungus. This disease has to be treated very quickly and it could be a bit too late as your tree already shows a lot of damages and it is a disease easier to prevent than to treat. The damages that are symptoms of the disease to be watched, are the little bumps and the little splits on the trunk. You can still give your tree a chance with first a treatment with copper spray. Be very careful to do not overuse or overdose the copper spray. Copper spray is the best treatment against fungi but when overdosed it becomes dangerous for the environment (and the gardener too !). You can also try to dig out the little bumps you see on the trunks and treat the holes you make by doing so with tree wound painting or linseed oil. To prevent the disease, first get rid of all the little pieces of dead wood which are by your tree on the surface of your soil because they make a nice home for fungi. Every autumn "paint" the trunks of your fruit trees up to the base of their main branches, and the base of the main branches with a mix of lime. This is called to "whitewash". It is very important to whitewash the trunks because in the winter or early spring there are days when the bare trunks of the trees are heated by sunlight when the ground is still cold or even frozen and the temperature drops at night. The trees which are dormant at that time can "wake up" and start their activity too early or the trunks can start splitting because of the brutal changes of temperature and it is through these splits that the bugs or fungi can get inside the trunks and start damaging them.

You can find the receipt of this natural paint here: www.organicgardener.com.au/.../lime-based-whitewash
About cutting the damaged parts of the tree and letting it grow from its base, the problem is that your tree is in fact a grafted tree and the new shoot coming out of the ground is born from the rootstock and it will not necessarily be a weeping cherry tree. You could let it grow and then graft it with a branch of weeping cherry tree (if you want to learn how to graft trees of course). The first thing you need to do for the health of your tree is to protect the rootstock because it is too close to the ground and has been cut horizontally. On a tree, you should never leave a flat surface unprotected because water accumulates, enters the wood and makes it rot and it becomes a gateway for viruses, fungi and xylophagous insects. When you cut a part of a tree, you always have to cut it in bevel, so that the water slides and does not stagnate on the cut, then you must treat the cut with a waterproofing like linseed oil and of course you always sterilize the blades of the instruments you use with alcohol. If you buy a new cherry weeping tree, try not to buy a grafted tree, but if only grafted trees are available, look for a long rootstock that you will be able to plant with the grafted part well off the ground. Most of the time the rootstock top is covered with wax to protect it, it is a good point, but if you see that it is protected with wax AND cut in bevel, then you will know that it has been grafted by a good gardener.