Sudden oak death is a disease caused by the exotic water mold Phytophthora ramorum that has killed many oak and tanoak trees along the California coast since the 1990s. It threatens several plant species and has led to habitat and wildlife loss. While there is no cure, following regulations on movement of infected materials and preventative measures like burning and chemical treatment can help slow the spread. The document provides background on the disease, where it is located, symptoms, affected plants, prevention methods, and ecological impacts.

2. …
 Sudden oak death will continue to drastically
impact California’s coast unless we all do our
best to prevent the spread of this serious
disease

3. How has Sudden Oak Death
impacted the California Coast?
 What is S.O.D.?
 Where is it found?
 What are the symptoms of this disease?
 What plants are targeted?
 What can be done to prevent the spread of
S.O.D.?
 What are the ecological consequences?

4. What is S.O.D.?
 Exotic pathogen
 Unknown origins
 Discovered:1995
 Attacks at least 3 species of oak
 In 2000, new species of fungus discovered:
Phy to p htho ra :
 Phy to p htho ra ra m o rum
 Water mold (fungi like properties)

5. Where is it located?
 California  Oregon
 14 counties:  Curry County
Humboldt
Europe:


 Lake
 Sonoma  Nursery plants only
 Napa
 Solano
 Marin
 Contra Costa
 Alameda
 San Francisco
 Santa
 Clara
 Santa
 Cruz
 Monterey

6. …
 Exists  New Infection:
 Forest  Neighborhoods
 Wild lands  Urban areas
 Suburban areas
 Usually inland near
coast, humid areas  Predicted
 2010: WESTWARD
 2011: SOUTH &
EAST

7. What are the symptoms of the
disease?
 Cankers
 Localized dead areas in the bark of stems
 Caused by fungi, bacteria or insect
 Leaf spots
 Round blemish on the leaves
 Caused by fungi or bacteria
 Twig dieback
 Wilting and death of small season twigs

8. What plants are targeted by the
pathogen?
 Oaks
 Tanoak
 Camellia
 Rhododendron
 California Bay Laurel

9. What can be done to prevent the spread of
S.O.D.?
No known cure but preventative measures can be taken
Burning
Removing bay laurels

10. …
 Chemical treatment
 Agri-Fos fungicide
 Phosphate compound
 Injected or sprayed on trunk
 Takes 4-6 weeks for tree to absorb
 Applied twice the first year, wait 1.5 years then
apply in fall annually

11. …
 Following regulations for good management
and sanitation
 When moving host plant material within and from
regulated counties, must comply with state/federal
rules
 Follow established trails and respect trail closures
 Clean and remove all soil before leaving invested
areas
 Clean and disinfect equipment used in infected
areas
 Report hosts showing symptoms

12. What are the ecological
consequences?
 Change in species
composition
 Loss of habitats for wildlife
 Loss of food sources for
wildlife
 Increased fire risk (change in
fire frequency or intensity)
 Soil erosion
 Decreased water quality
(increase in exposed soil

13. Overview
 New pathogen, not native
 Keeps spreading to counties, there are 58 and
14 have already been impacted
 There are other plants besides Oaks that are
infected.
 Symptoms leave plants to die 6-8 weeks after
symptoms show.

14. Overview
 There is no known cure for Sudden Oak Death
but preventative measures can be taken.
 Preventative measures include burning,
removing bay laurels, chemical treatment, and
following regulations for good management
and sanitation
 The ecological consequences of the disease
include trouble for wildlife, high fire risk, soil
erosion and poorer water quality.
 Sudden oak death will continue to drastically
impact California’s coast unless we all do our