Tree Diseases and Parasites
Diseases Common to Trees
The best way to ensure your tree does not get fataly harmed from fugi and bacteria is to take steps to prevent the incident from happening in the first place. Usually once a tree has noticable amounts of damage from disease it is too late to save it. You must prevent a tree from getting to this state long before it happens to effectively save the tree.
Identifying Disease - Anything that makes the leaves or bark on your tree look discolored or unhealthy is usually fungus. As seen in the picture above brown spots in the leaves or patches of discoloration in the bark are fungus that need attention. If your tree is affected by this it is a good idea to remove the sick or infected limbs as well as spray your tree with an anti fungal spray.
Prevention - There are little things you can do to prevent the spread of infection to your trees. If you notice surrounding trees are deeply infected it would be a good idea to cut them down so that the infection doesn't spread. You will also want to spray your trees with anti fungal sprays so that any fungus that does spread to your tree will be killed off immediately. Calling a local arborist to identify the type of disease will also give you a good idea on how to cure it. Most fungal infections are not immediately harmful to your tree but over time destroy your trees immune system which will kill it.
As with diseases, pests and insects are best taken care of in a preventative manner. Pests will eat away your tree from the inside out and lay eggs so that each season your tree gets weaker and weaker. If you notice caterpillars, ants, bettles, or any other type of bug crawling on your tree be wary. Look for inflamation in the trees bark or for eggs that the insects may have layed.
Prevention - If you notice swelling in the bark it is best to just cut the limb off to effectively get rid of the eggs before the insects spread. You can spray your tree with an anti pest substance that will kill eggs on the exterior of the tree as well as any other destructive species that may already be eating your plant. It is best to take steps to get rid of pests AS SOON as you discover they are there. Insects have the ability to destroy a tree in one cycle by having their eggs hatch.
Types of Insects
Root Feeding Insects - One of the most likely ways your tree is going to die from pests. Root feeding insects will feed on your trees roots effectively starving it of water and nutrients. It is nearly impossible to tell if these bugs are an issue unless you notice your tree dying without any other explanation why or an arborist tests your roots to tell you that root feeding insects are the issue.
Defoliating Insects - These insects feed on the leaves of your tree effectively destroying most canopies and slowing the growth of your tree. Typically the insects you will find munching on your trees leaves are caterpillars which are harmless except for certain types which reproduce massively destroying most of your trees leaves by the end of a season. Look out for tents that caterpillars will put up to hide in during the night, they consist of spider web like strings that form a sort of cocoon.
Bark Beetles and Bark Borers - These are the most destructive type of insect and require immediate attention if you want your tree to survive. These bugs dig themselves into the bark thus preventing normal movement of water. Their eggs also cause swelling in the bark and the larve will eat through the tree causing further destruction.