Leafhopper Phenology Study

Leafhopper insects can spread phytoplasma pathogens that cause X-disease in cherry trees. Managing leafhoppers is difficult, so we are working to identify where and when different leafhopper species occur to help with decision support. Since 2022, we have traveled to 10 orchards weekly from Peshastin to Richland to quantify leafhoppers on sticky cards and vacuum samples, and additional vacuum sampling is being conducted in Hood River, OR.

With the data, we will make degree-day phenology models for leafhopper X-disease vectors so growers can predict when leafhopper risk is highest.

Leafhopper Phenology

Information on X-disease and the leafhopper vectors is being kept up-to-date on the WSU fact sheet. It is currently thought that six species of leafhopper are vectors of X-disease phytoplasma. Among them, the species Colladonus reductus, Colladonus geminatus, and Euscelidius variegatus are the most common in Washington, and E. variegatus is probably not very good at spreading the disease.

Currently, we have data from sticky card monitoring data from 2022 and partial data from 2023. Leafhoppers from vacuum samples are still being quantified. Data from both methods will be shared and compared when ready.

With available data, we have seen in 2022 and so far in 2023 that C. colladonus is the most common leafhopper found in orchards on sticky cards. Data from 2022 and data from 2023 (still in progress) are shown below. This website will be updated as new discoveries and interpretation occur.