We noticed that you're using an unsupported browser. The TripAdvisor website may not display properly.
We support the following browsers:
Windows: Internet Explorer, Mozilla Firefox, Google Chrome. Mac: Safari.

Just how bad are the black flies/mosquitos in July?

Swansea, MA
Level Contributor
335 posts
11 reviews
Save Topic
Just how bad are the black flies/mosquitos in July?

I am planning a trip in July 2009. I know that bug spray is required but how bad are they on a scale of 1-10 (1=What bugs? 10=I would rather be anywhere but here!)?

Level Contributor
1,275 posts
46 reviews
Save Reply
1. Re: Just how bad are the black flies/mosquitos in July?

Once again, this depends on the weather. Only rarely in the past 14 years have I seen black flies. Many summers I get through the season with practically no bug spray, other wet years it is necessary. Some areas are worse than others, near the lakes around Polebridge mosquitoes can be bad. One of the things I love about living in Montana is that the mosquitoes are not normally a nuisance. The worst summer I'd experienced, 2 years ago, I'd put it on a scale of 6. This past summer, spent one week in the Bob Marshall Wilderness and in our group of 12 the bug spray was used once or twice, and by just a few folks. Horse flies were annoying, but we solved that with long pants and sleeves.

If you have bee sting allergies, be sure to bring an eppi pen.

More good news: no poisen oak or poisen ivy! No poinsenous snakes! Keep a holler out for bears and you'll be fine.

Level Contributor
16 posts
1 review
Save Reply
2. Re: Just how bad are the black flies/mosquitos in July?

not always a straight number answer to this question, but i'd agree with previous post. The worst I've had with flies is in the backcountry backpacking. I have had no problems down low with flies. Mosquitos can be a problem in the backwoods trails, especially south of goat haunt towards kootenai lake and around johns lake just off GTTS.

Charlotte, North...
Level Contributor
1,552 posts
14 reviews
Save Reply
3. Re: Just how bad are the black flies/mosquitos in July?

Yes, I agree that it just really depends. When I visited Glacier in early July 2006, the only place that I had troubles was in the Two Medicine area. Specifically, when we hiked to Cobalt Lake, we had a really bad time with both mosquitos and with black flies. Other than that hike, they were not an issue. When we visited Glacier again in late July/early August this summer, we experienced a good deal of mosquitos along the Dawson Pass Trail. There were no black flies, and elsewhere in the park mosquitos were fine.

So, from my experiences the Two Medicine region of the park seems to be a little worse than most, but the beauty of the area more than makes up for the slight inconvenience. I would certainly take some Off Deep Woods or whatever other repellent you typically use. Other than that, a hat and sunglasses would be good ideas.

I hope this helps,


4. Re: Just how bad are the black flies/mosquitos in July?

-:- Message from TripAdvisor staff -:-

This topic has been closed to new posts due to inactivity. We hope you'll join the conversation by posting to an open topic or starting a new one.

To review the TripAdvisor Forums Posting Guidelines, please follow this link: http://www.tripadvisor.com/pages/forums_posting_guidelines.html

We remove posts that do not follow our posting guidelines, and we reserve the right to remove any post for any reason.

Removed on: 12 October 2009, 17:35