Forage and Grain Crops 
Agronomy 105's Weed ID
Grain sorghum
Grain sorghum is also often referred to as milo.  Most of the sorghums that are cultivated are the dwarf types which grow to heights of about 4 feet.  The taller plants in that are often found interspersed in sorghum fields are outcrosses or reversions back to the taller types from which the dwarf varieties where derived.  Grain sorghum is especially well adapted to areas that are too dry for economical production of corn.  Generally in areas that receive enough rainfall or where irrigation is available, corn will be more economical than Grain sorghum. 
The grain of sorghum is essentially used for the same purposes as the grain of corn.  Grain sorghum is not grown much in Indiana primarily because our wet autumns do not allow the sorghum inflorescence to properly dry.  Birds which eat the immature sorghum seed can also be a problem for sorghum growers. 
The seed of grain sorghum is round, rust colored and often is covered by small dark spots.  This is not an indication of disease but simply normal coloration for sorghum seeds.