The insects in your photo look like aphids (Hemiptera, aphididae), however identifying them any further would require more information and possibly examination under a microscope. Some aphids are very host specific, so knowing the plant they are on can tell you the species of aphid. Others are generalists, so they can feed on many plants. I would suggest you re-submit this as separate questions for each host plant (e.g. what are these aphids on my asters?) and/or submit specimens to the MSU plant and pest diagnostic clinic (pestid.msu.edu). There is also a free plant diagnostic walk-in clinic every Wednesday from 10am -2pm at the Grand Traverse MSU Extension office (520 W Front St, Traverse City), if you would be able to travel there.