Specialist Interview with David Yarborough

PhD, Former Extension Blueberry Specialist and Professor of Horticulture

  1. What is your current position and how long have you served in this position?

I am the Blueberry Specialist with Cooperative Extension and Professor of Horticulture in the School of Food and Agriculture at the University of Maine*. I have worked as a research scientist and Extension specialist providing wild blueberry growers with research based knowledge at the University for the past 40 years.

* David retired in the Spring of 2019.

  1. Please describe changes you have observed in the weather since you’ve started in your position. 

As a graduate student working in wild blueberry fields in the 1970’s I observed that there would be a killing frost by the end of September, now this does not occur until the end of October or into November. There is both an earlier spring and a later fall that has increased the growing season. But there also have been more erratic frosts and freezes in fields with more variation in the temperature. There also been a trend of higher summer temperatures and less summer precipitation with fewer rainfall events but with more rain at individual events.

  1. What types of impacts have these weather changes had on the agricultural sector you work with? 

The longer growing season has allowed the expansion of wild blueberries in areas away from the coast with a reduction in coastal fields that have a higher value as house lots. So there are both positive increases in land and yields. But we also have seen an increase in leaf diseases and with new insects that threaten to limit production. This uneven precipitation now requires irrigation to ensure fruit production will not be reduced. But we will have increased costs to prevent losses from new insects such as tip worm and diseases such as rust that are found south of Maine, and increased incidence of summer drought. Ticks have also spread into wild blueberry fields and diseases they vector such as Lyme can cause serious diseases and reduce the quality of life.

  1. How have the farmers you work with responded to changes in the weather?

Land has been cleared North in both Maine and Canada, shifting the production North in Maine and increasing the number of acres under production in production In Canada. Larger growers have been investing in irrigation systems to supplement water for drought and in some cases for frost protection. Growers have been practicing integrated crop management to monitor for weeds, diseases, pests and fertility to prevent crop loses and improve yields. The University of Maine has been supporting this effort through IPM training and weather monitoring for disease prevention.

  1. What strategies do you suggest farmers consider to adjust to changing weather?

Utilize the resources provided by Cooperative Extension on the website and list serve to monitor for insects, weeds and diseases to prevent losses and use wild blueberry management tool to choose the appropriate inputs to remain profitable. Invest in irrigation and choose inputs wisely for the optimal economic return not for minimum inputs or for maximum yields. Use preventive measures to limit tick exposure and monitor and remove ticks when leaving the fields to prevent infection.

  1. What tools or information would be most helpful to the farmers you work with in order to respond to the issue of changes in average weather or weather variability?

Accurate models to predict insect and disease outbreaks and support for accurate weather data to support them.

  1. What types of federal and/or state policy initiatives would support your stakeholders to make adaptation or mitigation investments, and reduce losses associated with weather variability?

Support for investment in irrigation systems and affordable insurance programs to stabilize income from climate related losses.