Could also be hornets. Sometimes they are very aggressive so be carefull. Here's a shot of a hornet's nest:

http://en.wikipedia.org/wiki/Image:CopperNest.jpg

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250