Natural Resource Conservation Service of Missouri has information online regarding federal programs such as Environmental Quality Incentives Program (EQIP ), Wildlife Habitat Incentives Program (WHIP), Wetland Reserve Program (WRP), Grassland Reserve Program (GRP) and others.
You can also find information on the Plant Materials Center, a plant ID guide and an online version of Central Region Seeding ID Guide for Native Prairie Plants.
To go to the official site for soils information, click on the Web Soil Survey (WSS) button on the Missouri NRCS page.
Missouri Department of Conservation (MDC) has a good website for information on everything from permits and endangered species to native plants and invasive species. Fill in the "search box" if you don't find what you need under the quick links or by subject.