While the bees and wasps were working the flowers and providing sound effects, the blueberries had a couple of silent visitors.
Painted Lady (Vanessa cardui)
A Painted Lady (Vanessa cardui) stopped by for a very brief moment. She had hardly landed and she was off again. I barely got the one photo.
Olive Hairstreak (Callophrys gryneus) On th other hand, an Olive Hairstreak (Callophrys gryneus) stayed for quite a long time. I almost didn’t notice it since it is a small butterfly, about 3/4-in long, and it was moving quietly and spending quite some time at each bloom. This particular butterfly was very patient and gave the impression of being oblivious to the fact that I had the macro lens almost touching it. Interestingly, this specimen doesn't have much olive color. It also took some time to identify since I was looking for the color rather than the markings. Once I concentrated on the markings, I quickly identified it.
Additional identification resouces: Bugguide.net
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When the blueberries were in full bloom, the bushes seemed to be humming. At first glance, it looked like a mixture of just honey bees and bumblebees were responsible for the sound. Closer inspection showed that
European honey bee (Apis mellifera)
European honey bees (Apis mellifera) and 
Eastern Carpenter bee (Xylocopa virginica)
Eastern Carpenter bees (Xylocopa virginica) – not bumblebees - were responsible for most of the activity.
Common Eastern Bumblebee (Bombus impatiens)
Common Eastern Bumblebees (Bombus impatiens) were in a minority compared with the other two.
A few halictid bees (Lasioglossum sp.) – ‘left over’ from their earlier pollination activities in the pear trees where they were the only bees working the flowers – and Northern Paper Wasps (Polistes fuscatus) were working the blueberries.
Obviously they did a good job.
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