Common Weeds 
Agronomy 105's Weed ID
Velvetleaf, often called Butterprint, Indian mallow, or Buttonweed, is a difficult weed to control in the Midwestern U.S.  It becomes a major problem in cultivated fields, especially those with corn or soybeans.
Velvetleaf seedlings
The plant gets the name Velvetleaf from the characteristic velvety appearance and feel of the leaves and stems.  The leaves are large and heart-shaped. 
The name Buttonweed comes from the 'buttony' appearance of the seed pods.  Flowers are a bright, gold-yellow color.
Mature Velvetleaf plants are often 3 to 6 feet tall.  The seed pods contain relatively large, heart shaped seeds with one lobe of the heart being larger than the other.  Seeds can last in the soil for up to 40 years.