Hi,
It's my second spring/summer with a garden in Montreal and I'm noticing lots of lady beetle larvae/pupae this time of year. They are very aggressive aphid eaters, and the pupae are very cool looking. I had no idea what they were at first, but found a great web page or two using Google images search. For example:
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will they take care of saw-fly larvae? My observation is that they seem to flee them, as they flick their tails at them... This is my biggest frustration with my roses, as I don't want to use pesticides. I end up picking them off by hand, or cutting the new growth once it shows signs of laid eggs (trauma to the fine branches). It's tedious, and I wish there were some natural predator to take care of that for me.