Learn about trees | TheUnion.com

Learn about trees

I am a certified arborist, and it is our duty to be responsible for the welfare of trees. Recent action by our Empire Mine foresters is doing just that. This is not an excuse just to remove trees. A little beetle education is timely here.

Trees are organisms that become stressed and decline in a downward spiral due to many factors. They are:

1. Old age

2. Growing in dense groupings which results in water and nutrient competition for each tree.

3. Drought conditions which occur in our Mediterranean climate – hot, dry summers.

4. Damage by animals, weather (wind blown, lightning strikes), fires and abuse by humans. Yes, we are the trees’ worst enemies when we destroy their roots when we cut them, putting foundations next to them, paving up against trees, burning trash next to them, giving them a disease called moweritis, creating wounds in their bark, and planting lawns over their roots.

How do beetles work? They have an extraordinary sensory mechanism that detects weakened trees. The trees give off an odor revealing this condition. A mass attack by the adult beetles occurs. They chew their way through the bark and lay many eggs. The eggs change into larvae (white worms) which voraciously chew (you can hear them) destroying the water and food vessels. When this happens the dark green color of the foliage changes to light green, then to brown and eventually to red. This is important to understand – the worm changes into the adult stage, emerges through the bark and flies to neighboring trees to bore its way in and do the same damage. It isn’t just one beetle but hundreds of them.

When beetle infestation is detected it is essential that the trees be removed in order to stop this cycle. We do not have any means available to keep beetles off of trees.

We must become knowledgeable about how to keep from abusing trees that leads to stress. Healthy trees do not attract beetles. The California Department of Forestry and Fire Protection knows how to keep trees healthy – trust them.

Jean Pliska

Lake of the Pines

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