We have the remains of an old orchard on our property - several apple, pear, plum and cherry trees. Found the sawfly on the humming bird feeder hanging on a cherry tree.

Could it have come from one of the trees or was just attracted by the sugar? We also have flower beds and a large vegetable garden nearby, plus conifers, so don't really think this narrows it down!

Ha. Yeah, sounds like my place in that, unless I specifically find an insect actively feeding on/in a plant, there's enough diversity of habitat and plant species here that it's almost pointless to speculate as to a possible association. :-)