For each plant known to occur in Illinois, Mohlenbrock and Thomson have included a complete description, illustrations (106 in all) showing diagnostic features, distribution maps (95), and ecological notes. The authors also present keys to aid in the identification of the plants.This volume includes one familythe Polygonaceaefrom the large order Chenopodiales, and two orders in their entiretythe Hamamelidales with two families and the Fagales with three families."