I'll be looking for the next 3-4 weeks, after which this species enters decline and nests are no longer active.
The species is the common aerial yellowjacket, Dolichovespula arenaria. It is in the same genus as the bald faced hornet (Dolichovespula maculata) which builds similar nests and is actually a type of yellowjacket, not a true hornet (genus Vespa).
These guys are in some ways more challenging than working with honeybees, in that they are typically much more aggressive than honeybees, and studying them requries finding new nests each year. Plus, their biology is much more poorly understood, which makes it both more exciting and challenging to study their behavior and ecology.
I've attached a photo of a nest in observation boxes I have set up, and here's a link to a video of a fascinating behavior I'm currently investigating, when workers kill their queen in some colonies. They are like honeybees in many ways, though there is much more conflict among colony members over who gets to reproduce, and in some colonies this appears to lead to outright violence!
Kevin also adds:
Posted by simon at July 24, 2012 5:18 AM in Cornell
I'll be collecting nests this year and again next year, so if folks want to contact me, they can email at firstname.lastname@example.org.