Diversity and abundance of native bees in orchards are significantly impacted by the timing of the apple bloom

Commercial fruit and vegetable agriculture is dependent on bees for pollination services.  In the following study, we investigated native bee abundance and diversity in Georgia apple orchards over the entire growing season with special emphasis on the apple bloom during four years.  2010 was a traditional apple bloom dominated byAndrena species.  In 2011 and 2012, the apple bloom occurred 2 to 4 weeks early.  During these blooms, much lower Andrena species were present; however, greater abundances of Osmia species and other non-Andrena bees were documented. In 2013, the apple bloom was 2-3 weeks later than the traditional bloom.  Interestingly, diversity and abundance were much higher than in the previous years.  In order to use native pollinators successfully in commercial agriculture, we will need to gain a better understanding of these dynamic systems.