"Remote Sensing to Detect Mite Infestations in Stone Fruit Orchards" Adam Hale and Minghua Zhang Land, Air and Water Resources – UC Davis 2/14/07

Project Objectives  Use aerial images to detect and track mite infestations in stone fruit orchards during the growing season  Investigate the possibility of saving growers money by lowering monitoring costs

Project Tasks Collection of Data - Field Level Data - Aerial Images Analysis of Data

Field Data Gathered  Noted the level of mites on selected trees –Based upon the UC IPM for stone fruit guide  Used a remote spectrometer to collect reflectance data

Low (1-20%) - an occasional mite on occasional leaf; hard to find. Low/Moderate (21-39%) - mites easier to find but no colonies or webbing and few eggs. Moderate (40-60%) - some leaves without mites, other leaves with small colonies; eggs easy to find but very little webbing. Moderate/High (61-79%) - mites on most leaves, colonies with eggs, and webbing on some leaves. High (80-100%) - lots of mites on most leaves; eggs and webbing abundant. UC ANR Integrated Pest Management for Stone Fruits, Publication Mite Ratings

Spectral Reflectance Curve

Aerial Images – Kearney Ag. Center Manning Avenue True Color Image Color Infrared Image Study Area

Frequency of Observed Mite Rating

7/21/06 - Images Mite Level

8/4/06 - Images

Mite Level 8/12/06 - Images

Mite Level 8/21/06 - Images

Results  Spectrometer shows that there is a difference between healthy and unhealthy trees  Image analysis shows that there is a possibility to use remote sensing to detect mite infestations

Economics  While this aspect of the project needs further research this study hopes to determine: –If there is a savings on monitoring costs  Image analysis vs Field scouts –If remote sensing analysis can be quicker and more efficient at observing mite outbreaks than current methods

Feedback  Is the mite rating scale appropriate?  What is your threshold limit?  Do you think this method of mite detection would be useful in your field?  Would you be willing to participate during the coming season?