Reddit mentions of Identifying & Harvesting Edible and Medicinal Plants (And Not So Wild Places)

So here's the guide that I use. Also you have other options that you can use as well. You can download apps (or Google search) for use in the field to augment the pictures in your guide of choice.

The best method in my opinion would be to go out with my guide of choice and start with something super easy to identify like dandelion (because it's prevalent and there are no poisonous lookalikes). Look at your field guide and look how it describes the basal rosette leaf formation, the tooth shape on the leaves, etc. Once you have the easy stuff down you can move on to more advanced identifications.

I know for most of the new people this goes without saying, but I just wanted to say that you should always be 100% sure of your identifications, because there are poisonous lookalikes out there that will do stuff from give you the runs to kill you. Any field guide worth its salt will point out any these lookalikes.

Another thing I like to stress to new foragers is the rule of 10%. Basically this: Not all plants reproduce and spread like crazy. Some guys (like ramps, wild ginger, or ginseng) take a long time to get a good foothold in an environment. With that said you should only take 10% of what's there or only what you need (whichever is less). Now with all rules there are exceptions; exceptions for the above rule would be things that go nuts when it comes to reproducing and out competing everything else around it (most of the time because it's not from there). Examples of this would include dandelion, japanese knotweed, japanese stiltgrass, japanese barberry, mugwort, plantain, and others that are escaping me at the moment.

Also, I should mention that Ohio is pretty good for foraging. There's a lot of invasive plant life there (not so much as on the East Coast, but a great deal all the same) so you should be able to find a lot of good stuff.