Black flies: May not bother you. They have been sighted on Mount Royal at times. (They are rampant in New Brunswick, first place I met them. ARGHHHH!) You would probably do better to stay on the south shore and drive into Montreal - for less expensive. Beautiful Chateauguay Valley on your way up. Too bad you did not plan to attend Apple Hollow Fest in mid July but there is a very popular music venue in Ormstown area. Check Backwater Blues myspace site. Very poor planning! You may still have black flies in upstate NY. They thrive in evergreen forest areas but usually are gone by end of June. Dragon flies love them - to death. I LOVE dragonflies! A reasonable dose of B vitamins - not excessive - seems to alleviate the biting. The nice thing about black flies is that, unlike mosquitoes, they do not like to be indoors and try to get out rather than bite. However, they sneak attack - soundlessly. Light coloured clothing helps.