Enhancement of pollination by native bees in blueberries and cranberries

Project Overview

Project Type: Research and Education
Funds awarded in 2008: $183,271.00
Projected End Date: 12/31/2011
Region: Western
State: Oregon
Principal Investigator:
Dr. Sujaya Rao
Oregon State University

Annual Reports


  • Fruits: berries (brambles), berries (cranberries)


  • Education and Training: extension, on-farm/ranch research
  • Production Systems: general crop production


    Pollination is critical for production of blueberries and cranberries. In the Pacific Northwest, growers rent honey bee hives for pollination. However, honey bees do not perform as well as native bees in these crops due to prevailing weather conditions during bloom and due to their preference for other flowers in which nectar is easier to access. In contrast, native bees forage in wind, rain and on cloudy days. Also, economically, native bees are less expensive and invasive. Hence, the study was conducted to determine strategies for enhancing populations of native bees for increasing pollination and improving yield and grower profit.

    Project objectives:

    Our long term goal was to enhance native bee populations in berry fields for augmenting pollination and thereby increasing yield and income for berry producers. In this project, two separate programs were integrated into one, with similar experiments conducted in blueberry fields in the Willamette Valley and cranberry fields on the coast. Our objectives were to:

    1. Estimate native bee pollinator species diversity and abundance in berry fields.

    2. Compare honey bee and bumble bee foraging behaviors in berry fields.

    3. Evaluate the impacts of insecticide sprays on native bees.

    4. Examine strategies for enhancing native bees in berry fields.

    5. Build capacity in growers to identify, protect and enhance native bee pollinators in their fields for increasing berry production.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.