Skip to main content Skip to navigation

Plan for Multiple Fire Blight Conditions, Be Agile

View Print Version

Written by Tianna Dupont, WSU Extension; Ken Johnson, OSU, Revised April 6, 2020

The last few years have built up fire blight inoculum in our orchards. Consider designing a toolbox of plans you can choose from depending on the risk in each block and how spring progresses.

Think about which are your high-risk blocks: blocks with sensitive varieties, high-value varieties or a history of fire blight. Those are blocks where you may want a more intensive program. Think about what fickle mother nature may do. Have a plan for moderate temperatures and extended bloom as well as flash bloom. Below is an example of a set of plans a grower might design to choose from for different blocks and conditions.

This is a table showing the fire blight control plans for apple. IT outlines procedures for conventional orchards under low to moderate pressure and high risk. It also shows plans for organic orchards for east to thin varieties, Hard to thin varieties or short bloom periods, and hard to thin varieties and long term bloom periods.

This is a table showing fire blight control plans in pear for conventional orchards under low to moderate risk and high risk situations. It also shows plans for organic pear orchards with east to mark varieties (Anjou & Comice) and marking tolerant varieties (Bosc).

For more information see:


Tianna DuPontImg1380

WSU Extension Specialist, Tree Fruit

Office: (509) 293-8758

Mobile: (509) 713-5346


Use pesticides with care. Apply them only to plants, animals, or sites listed on the labels. When mixing and applying pesticides, follow all label precautions to protect yourself and others around you. It is a violation of the law to disregard label directions. If pesticides are spilled on skin or clothing, remove clothing and wash skin thoroughly. Store pesticides in their original containers and keep them out of the reach of children, pets, and livestock.

YOU ARE REQUIRED BY LAW TO FOLLOW THE LABEL. It is a legal document. Always read the label before using any pesticide. You, the grower, are responsible for safe pesticide use. Trade (brand) names are provided for your reference only. No discrimination is intended, and other pesticides with the same active ingredient may be suitable. No endorsement is implied. articles may only be republished with prior author permission © Washington State University. Republished articles with permission must include: “Originally published by Washington State Tree Fruit Extension Fruit Matters at” along with author(s) name, and a link to the original article.

Washington State University