|Steps to take to slow the spread of Sudden Oak Death
Sudden Oak Death has killed thousands of stately oak trees in California. As its
name implies, the onset of the disease and subsequent death of the oak is precipitous.
First reported in Marin County in 1995, Sudden Oak Death is caused by a previously
unknown pathogen species named Phytophthora ramorum (Pr). Usually Phytophthora
are found in low-lying areas with lots of moisture. They first infest roots, spread
through the plant, then progressing to the leaves.
Recently, research has confirmed that Coast Redwoods and Douglas Fir are hosts
to the disease. Infected redwoods have been found at Henry Cowell State Park among
other sites. Trees dying from Pr. often are found on dry hills. Bay trees appear
to be infected only in their leaves. Bay leaves can host so many spores that the
spores cannot be counted, even with sophisticated equipment.
No one knows where the disease originated. The genus Phytophthora includes the
species that caused the Irish potato famine, causing some speculation that the
disease came from Europe. Nor does anyone know what will be the final result of
Sudden Oak Death. Little is known of the long-term ecology of forests, especially
those in which substantial growth occurred after the advent of fire suppression
at the turn of the last century. Dutch elm disease and chestnut blight took about
50 years to spread across the country and destroy those tree populations.
How you can slow the spread of Phytophthora:
- Do not collect any plant material including leaves, flowers, acorns, twigs,
wood and bark.
- Park your vehicle only in designated parking areas because spores may collect
in mud on your tires and spread to other areas.
- Stay on established trails and respect trail closures.
- Avoid areas of damp soil or mud when walking, biking or horseback riding to
prevent the pathogen from hitch-hiking.
- Clean soil and mud off shoes, bikes, vehicles and horses hooves to prevent
spreading the contaminated soil.
- Clean woodworking tools with disinfectant.
- Visit this website
for more information
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