Sometimes when driving across a state, you run into topography that seems a little out of place. For Iowa, it's the Loess Hills, which stand out even in comparison to the hilly ground of southwest Iowa's cow-calf country. These hills are made of deposits of loess that aren't found in this amount anywhere else, with the exception of China's Loess Plateau.
Interestingly, these hills also support wildlife that would normally be found on the Great Plains further west. This includes reptiles like six-lined racerunners and prairie rattlesnakes, and plants like yucca and cowboy's delight, according to the Loess Hills Preservation Society – which uses a yucca as its logo.
The hills are also the largest portion of remaining native prairie in Iowa, although the amount of native grass is in decline, mostly thanks to the invasive eastern red cedar. Of course, a big feature of native prairies that stands out, especially for ranchers, is the abundance of warm season native prairie grass like big and little bluestem and Indiangrass. Driving through the Flint Hills of Kansas, this is very apparent, with grass going dormant during the winter, compared to the cool season grasses I'm used to in northwest Missouri and southwest Iowa.
But the Loess Hills definitely have their own riverside flavor to them, being formed by highly-erodible loess, or silt blown in from the Missouri River floodplain around 24,000 and 14,000 years ago, according to the Preservation Society website. It's no surprise that the other locations known for having loess are along rivers – along the Yellow River in China, and to a lesser extent, along the Mississippi-Yazoo bluffs "way down around Vicksburg."
While the hills mostly cover Iowa's western border, it's seems easy to forget that they extend south along two counties in Missouri, around the Mound City area. I found this out firsthand on an interview earlier this week, when I crossed the bluffs that looked very similar to those I camped in while in Boy Scouts – ironically just across the river from Iowa Point, an unincorporated Kansas community that was once a Missouri River ferry crossing, and where river bottom fields contrast with the bluffs on the other side.