It comes in very handy to have field guides written specifically for your state or geographic area. It saves many minutes thumbing through books bypassing entries that will never be seen in your area. Here are some of my favorite field guides for Indiana:
Indiana Wildflowers by Kay Yatskievych — this is a very thorough book, including all the herbaceous species known to exist in Indiana. There are many photos (about 1 for every 3 plants) and also many drawings. Sometimes it takes me longer than I would like to find a specimen, but this is most likely because the book contains so many entries.
101 Trees of Indiana by Marion T. Jackson — a very user-friendly book with many photographs for each entry as well as drawings of twigs, leaves, and blooms. Each entry also contains a map so you can see which parts of the state have this tree growing in it. A must-have!
Butterflies of Indiana by Jeffrey Belth — an excellent guide to butterflies that frequent our state including identification of adult butterflies by color, guide to eggs, guide to larva, guide to larval hosts, and a wealth of other butterfly-related information.
Wildflowers of Holliday Park by Norma Bangel Wallman — this guide is for a park in the city of Indianapolis which means that its information is relevant for the surrounding areas. While this guide will not provide pertinent information for all areas in Indiana, it is invaluable for those in the area around Indianapolis. It is always helpful to do a little research and find out if there are guides specific to your own area.
Birds of Indiana by Stan Tekiela – this small guide includes one large photograph per bird, a symbol to indicate during which parts of the year this bird can be found in Indiana, information about size, coloring, eggs, fledging, migration, food, and other relevant information. Again, very handy for having all the birds you might routinely see in one place.
Wild Berries & Fruits by Teresa Manrone — this wonderful little berry guide is organized by color and provides excellent photos as well as habitat, growth, leaves, fruit, season, comparisons, and whether or not the berry is toxic, edible, non-edible, or tasty!
Please note: this post contains affiliate links. All opinions of these books are my own.