The best help for learning to identify nuts is a pictorial guide. Most include information about common tree nuts such as almonds, pecans, pistachios and walnuts as well as ground nuts such as peanuts. If you’re gathering nuts outdoors, learn the varieties of nut-producing trees in your area. You can get this information through your county’s agricultural extension office.
Most nuts, either in or out of the shell, have distinct sizes, shapes and flavors. Beginners should find a farmer’s market or other store that sells nuts in the shell, and buy a few of each variety they’re interested in learning about. In addition to common varieties used in cooking, you should also find chestnuts, Brazil nuts and hazelnuts in the shell. If you can’t find examples in the market, check out a field guide from your local library. Field guides also offer examples of more exotic and harder-to-gather varieties such as macadamia nuts and pine nuts that may not be available in the shell in local markets.
Another way to learn about different types of nuts is gathering them in the wild. To do this safely, take a field guide that’s keyed to the local region. This kind of field guide teaches about identifying nut-producing trees by their foliage and what nuts look like when they still have the thick fruit covers that hide their shells. The guide also tells when each variety of nut is ready to harvest.