Bumble bees of Western America (Hymenoptera: Apoidea)

Published November 1957. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalogInformation contained within documents may be obsolete. Please check for recent information at the OSU Extension Service website: http://extension.oregonstate.edu/catalog/results.php?cat=Agricultur