Do you recognize this seed pod? It is from the annual weed I always called Buttonweed. By late summer the plant forms these characteristic pods. Each vertical segment contains from 2-9 seeds. It is 1 inch across. Later they split open for seed dispersal. Notice the many hairs.
It is a member of the mallow family. The plant Abutilon theophrasti is native to China and India. It was used as a fiber crop in China since 2000 BC. The stem has long fibers suitable for cord, rope, binder twine, fishing nets, coarse cloth, paper and a caulk for boats (Mitich 1991; Spencer 1984). The seeds are edible.
It was apparently introduced to North America before the 1700s. Records show it was cultivated along the east coast for its fiber content. It is now widespread in the croplands of the U.S. and Canada and is considered a weed pest. It was one of the targeted weeds Dad told us to not miss when we walked the soybean fields in the summer.
Known for its ability to thrive in disturbed soils, it grows in the worst of conditions. Here are two examples I found in weedy patches by the trail. 
The leaves are heart shaped with a point at the end. They and the stem are covered with fine hairs. Even the seeds have a fine hairs. The seeds are very durable. They can pass through the gut of animals unharmed. They can remain viable up to 50 years before germination.
Our View From Iowa 