Barred owls are large brown owls and their calls are often heard at dusk and through the night due to their nocturnal behavior.

This series of pictures shows the traits and presence of the prickly pear cactus in different seasons. 

One tree in this forest is not standing upright like the other trees.

Stomata in tulips are important parts of the photosynthesis and cellular respiration processes.

The Iowa Wind and Rock is a physically demanding bicycle race in Iowa.

Animal scat can be examined to determine evolutionary relationships in the animals.

Chloride levels were tested and monitored in several local waterways after the first snow melt to determine street salt impact on local waterways.

Startled fish cause a wave surge as their individual movements constructively interfere.

Icicles on a roof appear to be sideways, rather than perpendicular to the ground.

The state has a variety of surface water and underground water resources.

Many people believe Iowa's landscape is nothing more than flat plains. However, the landscape in northeast Iowa is very different than the rest of the state.

During the early Paleozoic, much of Iowa was covered by a shallow sea.

Lake Superior agates can be found in and around the Volga and Turkey rivers.

Rime ice and hoar frost are two processes that occur during freezing temperatures.

A fallen oak log is slowly being decomposed by saprophytic turkey tail mushrooms.

Grannis Creek falls is a moderate-sized, spring-fed stream in the karst topography of Iowa's Driftless Region.

A restored prairie is important to ecosystems.

Queen Anne's lace is an invasive species.