yana valachovic, brendan twieg and dan stark humboldt and...
TRANSCRIPT
Yana Valachovic, Brendan Twieg and Dan Stark Humboldt and Del Norte Counties UC Cooperative Extension
Funding provided by: USDA Forest Service, State and Private Forestry and SOD Research, American Recovery and Reinvestment Act, CAL FIRE
Since 2004 we have been conducting ground-based and stream monitoring for the pathogen
Installed many management trials to both control the spread of the pathogen and to learn how to protect high-value trees and forests
Developing a set of science-based tools to provide managers and landowners with resources to address the pathogen
Coordinating an inter-agency response team
• Ground Surveys: people on foot look for symptomatic vegetation and take samples
• Aerial Detection: people detect
mortality consistent with disease from an aircraft
• Stream Monitoring: detects when
pathogen is input—often from terrestrial infection—upstream of leaf baits
SOD Detection
Aerial Surveys
USDA Forest Service Aerial Pest Detection Unit (those boys & girls are good!) Maps all types of abnormalities
of all tree species Sometimes more focused SOD
surveys are conducted
‐ Can’t see trees under canopy ‐ Symptoms are not unique to P.
ramorum; ground sampling & lab testing still necessary
Aerial Surveys
Risk models
Meentemeyer et al., 2004
2001 Disease
Distribution
2014 Disease
Distribution
Most moderate-risk area here does not contain bay laurel; risk model here is driven by veg. types that include shrub-form tanoak or have tanoak associated commonly elsewhere.
Notholithocarpus densiflorus varieties densiflorus & echinoides
• Ten individuals of each var. from Trinity County (uninfected locations) – 6 branches per tree, each with
multiple sub-branches • 1 control • 5 inoculated
– Two strains each branch » Santa Cruz nursery-
origin » Trinity County wildland
origin
• Inoculate twigs and measure lesion growth
• Experimental design and bulk of lab work by the Rizzo Lab: Dave Rizzo, Heather Mehl, Kamyar Aram, et al.
Inoculations
Both varieties highly susceptible…
var. densiflorus (tree form) var. echinoides (shrub form)
Both varieties formed lesions that girdled the stems and killed all distal leaves • Do varieties differ in the frequency of such girdling lesions? • Do the two inoculant strains differ in virulence?
Notholithocarpus densiflorus var. echinoides
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Acres of SOD-consistent tanoak mortality identified by USFS Aerial Surveys
Unresolved issues How to clean heavy equipment?
California bay laurel stumps Equipment is working where trees have been fallen
Logging Equipment: Lots of Infested Soil
LOG LOADER: CAN HARBOR OVER 500
LITERS OF SOIL/DEBRIS