What is the minimum microscope strengh to view mushroom spores?

April 6, 2009 12:25 PM

How powerful of a microscope do I need to identify spores when mushroom hunting? Is 100x enough?

I am looking into mushroom hunting as a hobby and it seems the most reliable way to identify mushrooms is through microscopic examination of their spores. I would like to purchase a compact portable microscope to do this with. I have seen 100x pocket microscopes for under $50 but it seems like I might need something stronger. Any advice?

posted by tweaqslug to Science & Nature (3 answers total)

We use 200x in our lab to look at mycorrhiza spores. I'm guessing it would be similar for mushroom spores, but this may be overkill. With mycorrhiza sometimes the only differences in the spores are the color or the presence of a double wall, which are very difficult to determine at lower magnifications. If mushroom spores can be identified by shape only, 100x may be sufficient. I would, however, be wary of a 100x microscope that costs only $50 new -- the optics can't be very good. Your best bet may be to go to the surplus warehouse of a local university and pick up a good used 200x microscope for cheap.
posted by bengarland at 1:10 PM on April 6, 2009

My Eyewitness Handbooks guide to Mushrooms has this to say: "To identify spore shapes and sizes, you will need a good quality, but not necessarily very expensive, microscope. Ideally, enlargement should be x 1000, but good results can be obtained at only x 400." It also says, "Most spores are less than 20 microns long or wide, and many are smaller than 5 microns..." My husband looks at spores to identify mushrooms, and he says he can often get a good view at x 400, but only if he has an excellent light source and clean slides. Since his microscope goes up to x 400, he hasn't tried going lower too often.
posted by daisyace at 6:36 PM on April 6, 2009

No practical experience, alas (I share subby's need), but my calcs corroborate daisyace's quote of x1000, in order to discern the smaller spores. x400 would probably work for the largest 50% or so, as suggested.

Optical Engineer in my professional life.
posted by IAmBroom at 7:06 AM on April 7, 2009