Creates the Forests, Wetlands, and Prairies Act. Provides that the Department of Natural Resources shall prepare and maintain a comprehensive Forests, Wetlands, and Prairies Grant plan for the preservation and enhancement of forests, prairies, and wetlands in Illinois. Provides that the Department of Natural Resources, pursuant to the comprehensive plan and subject to appropriation, shall establish and administer a Forests, Wetlands, and Prairies Grant Program to restore degraded forest lands and native prairies, and to promote the growth of native vegetation that remove carbon dioxide from the atmosphere and help to mitigate the impact of climate change. Provides that units of local government are eligible to submit a grant proposal in a format and at a time prescribed by the Department of Natural Resources. Provides that grants may be used by units of local government to fund: (1) local projects restoring or expanding forests, wetlands, prairies, or other natural landscapes demonstrated to absorb carbon dioxide from the atmosphere; (2) education and marketing regarding local projects or steps community members may take to promote the growth of native vegetation that removes carbon dioxide from the atmosphere; and (3) any other purpose approved by the Department of Natural Resources that advances the State goal that there be no overall net loss of the State's existing forest, prairie, or wetland acres or their functional value due to State-supported activities. Amends the Department of Natural Resources Act and the State Finance Act to make conforming changes.