Signs and Symptoms - Signs and Symptoms - Proper treatment for any tree problem starts with the recognition of signs and the understanding of symptoms. A sign is some manifestation of the causal agent. The fungus fruit bodies, the oozing of bacteria, and the white covering of scale insects are signs of the problem. The discolored leaves, the wilted leaves, and the dying twigs and branches are symptoms of a problem. Great care must be taken to determine cause and effect. A tree weakened by compaction or over fertilization may be attacked by fungi and insects. To attack the secondary agents will not help the tree. This is a common problem. Bronze birch borer commonly attacks trees weakened by other agents. The birch trees may be shaded, or the roots injured by mulching or planting of bulbs. Or the birch tree may have been planted in the wrong place and it is slowly dying. The bronze birch borer is a weak opportunist that attacks weakened trees. The same can be said for many canker-causing pathogens. They are secondary. Fighting the secondary pathogen will not help the tree. It is extremely difficult to understand problems that take many years to develop. Many tree problems start at the time the tree is planted. The survival curve is downward from that time onward, but the tree continues to live in a very unhealthy state. Then some very obvious secondary pathogen arrives and all attention is given to the secondary pathogen. If the secondary pathogen is defeated, another one will take its place. Cytospora kunzei on spruce is another case in point. The fungus arrives after the tree is committed to an early death. Attacking the fungus will not help the tree. What may help the tree is a change in its treatment. Check the lawn. Is the lawn in very good condition without weeds? Suspect over use of herbicides and fertilizers? What about water? Has the lawn taken all the water? Has the conifer grown itself into a shaded or crowded condition? Too often spruce trees just grow themselves out of space. Scale insects indicate a weakened tree. One may kill the scale insect, but the tree will still be weak. Trunk and branch boring insects also attack weakened trees. Again, one may kill the insects, but the tree still has problems. My point in all of this is that we often attack the sign and symptoms and the secondary pathogen, and we never help the tree. When the sick tree is near a home or when people gather and walk by, at least 90% of the time, people and their activities will be the cause of the problem. Attack the cause, not the signs and symptoms.
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