Winter Moth Integrated Pest Management: City Fruit’s work with Urban Food Systems

In early November of 2020, City Fruit and the City of Seattle’s Urban Food Systems (UFS) team met to discuss a collaborative effort to manage the Winter Moth infestation in Seattle’s urban orchards. 

winter_moth_taping_pic.jpgIn partnership with UFS, City Fruit rolled out a Winter Moth Integrated Pest Management (IPM) strategy that included treatment of 65 trees over 8 public Seattle orchards.  This included orchards at the Rainier Beach Community Center, Martha Washington Park, Amy Yee Tennis Center, Maple Wood Playfield, Danny Woo Community Garden, Meridian Playground, Burke-Gilman Trail, and Carkeek Park.  City Fruit had researched strategies to manage this issue last year, and in our second year, we took note of where the Winter Moth was most prevalent on the tapes we secured. 

A key goal of our IPM strategy involved both assessment of pest presence in the orchards and implementation of a trapping control strategy.  On the ground, this involved wrapping each of the 65 trees with corrugated-paper banding material and applying a sticky insect barrier on the band.  Since we were trying to assess which orchards might have adult Winter Moths present, we began banding in November, when many adult moths emerge from the soil and begin their journey up tree trunks to mate and lay eggs. The process was time-consuming, as spreading the insect barrier on each band took effort, but thanks to the help of volunteers and our Board president, we were able to tape the trees, check and replace tapes when they started to fail, and retape all the trees before January. Our efforts were documented and shared with Urban Food Systems to consider further care for trees that might be susceptible to winter moths.

Moving forward 

With bands removed in January, there is much we can learn from continued monitoring and research on the Winter Moth. 

While some orchards showed no Winter Moth presence, others had large populations showing up on the bands.  What might explain the differences in infestation?  Are there ways we can improve mitigation and prevention strategies to protect trees and orchards that appear to be pest-free? 

Although we may not yet have full answers to these questions, we believe that inter-organizational partnerships, such as our collaboration with Pipers’ orchardists at Carkeek Park, can help contribute to the efforts to solve this problem. According to Don Ricks, a longtime orchardist at Piper’s, when our tapes showed no evidence of winter moths on those trees: “Without knowing it, you seem to have independently confirmed what I have seen as well… that the natural surroundings with the wooded area around Piper’s orchard seems to provide some sort of natural predation of the moths.” 

There is room to research and develop our understanding of the pests that impact the fruit and health of our Seattle fruit trees, both on public lands and on private ones. By experimenting with organic materials and documenting our findings, City Fruit hopes to help area orchardists and tree owners create effective pest management strategies that work for our trees. We believe that strength stands in collaboration with community and that a citizen-science level approach could greatly support efforts to not only collect data on Winter Moth infestation, but on future issues impacting our city’s fruit trees.