Diseases and Pest’s That May Confront Your Tree

Parasite Infected Tree

If you have a tree growing on your property you may be aware that it is vulnerable to a few conditions and pests.  In this blog article we want to lay out of few of those pests and diseases that you may have to deal with. First thing if you feel that your tree is infected with either pest or disease you can always give us a ring over at Las Cruces Tree Service to help with your needs. We are friendly and will give you some free advice. Sometimes, but not always, that advice is to have the tree removed.

Here is an excerpt from a book titled “Encyclopedia Trees And Shrubs” authored by Nico Vermeulen

Diseases, pests, and growths


Little attention is given in this encyclopedia to diseases. By following the guidance on appropriate growing conditions and location, any weakening of trees and shrubs should be avoided, so that disease is unlikely. The vegetation may well be eaten by animals but this is unlikely to do much real harm.

There are exceptions in respect of diseases, such as the infectious bacterial fire blight that affects trees in the Rosaceae family, such as apple, pear, and may. Dutch elm disease also affects otherwise healthy trees. There is no other remedy for both these diseases than removing and burning the complete tree.

Viral infections or fungi can cause growths that resemble bird’s nests, known as witches’ broom. The growths cause a tight ‘nest’ of small branches to form. They are most commonly found on birch trees and can give them a fairy-tale appearance. This marginally reduces the vigor


of the tree but is otherwise harmless. With conifers, this phenomenon is regarded positively, because it enables propagation through grafting.

Mistletoe is another growth that occurs. The mistletoe (Viscum album) is a parasitic plant whose roots enter the tree through fissures to


Betula pendula or silver birch with ‘witches brooms’


tap the nutrients in the sapwood. This usually occurs with fruit trees, may, willow, and poplar. Mistletoe is most noticeable in the winter because of its greenness against the otherwise bare tree. The host tree has to share nutrients with the parasite but this is not a real problem for healthy specimens. If the tree becomes heavily laden with mistletoe, it runs the risk of its branches being snapped off by strong winds catching on the foliage of the mistletoe.

The mistletoe seeds are pressed against the trunk of the tree by birds cleaning their breaks. Humans can sow the seeds by making a small cut in a branch.


Apparent plagues of moths often cause panic. Worried citizens frequently telephone the parks and gardens departments of local councils to tell them that their shrubs are being stripped bare by the larvae or caterpillars. This may be larvae of the brown tail moth (Eupoctis chrysorrhoea) which


Mistletoe (Viscum album) on a willow


cause a nasty irritation if touched, or one of the species of ermine moth (Yponomeuta) that gregariously gather together in tent like structures that festoon the affected tree. The caterpillars then pupate, protected against birds and other predators inside a chrysalis or cocoon. The stripped shrubs make a desolate sight. Fortunately the problem is only temporary. The pupae fall to the ground where they emerge. The shrubs quickly make new growth and are soon in leaf again.


Such pests do not usually kill a tree or shrub, making it unnecessary to use chemical insecticides. Indeed, insecticides can help to create problems with pests by destroying the”

These diseases and pests are just a few laid out here. If you notice anything at all odd about your tree than give us a ring and we have someone on staff to be able to let you know what it is. If we don’t know we can always find out for you!


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