What Trees are up Against

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InsectS

Insects can become pests when populations reach levels that threaten the health and/or aesthetic value of plants in the landscape.

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Diseases

When plants are challenged with unsuitable environmental or physiological conditions they become susceptible to pathogens that can cause disease.

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Poor soil

Soil composition and structure are basic building blocks for the health of every tree. Urban soils often suffer from lack of nutrients, poor water holding capacity, and lack of oxygen.


Signs of Tree Health Problems

Stunted/Reduced Growth

Discolored Foliage
(Grayish/bronze/yellowish green or straw colored)

Thinning out of canopy
(premature leaf drop)

Cankered stems

Death of individual branches


It takes all Three

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It takes all three factors for a disease or pest to infect a tree:

  1. Pest - Disease or a pest must be present

  2. Host - The tree needs to be a suitable species for the pathogen

  3. Environment - The environment needs to be suitable for the pathogen or pest to thrive