Aaron,

Drought and excessive deer browsed can certainly limit the production of soybeans.  I suspect those factors may have reduced the plot’s potential more than the planting technique.

The biggest hurdle to planting soybeans by using the broadcast method is insuring the seed makes good contact with the soil.  Soybeans do best when they are covered by about a half inch of soil.  This is much different than clover, brassicas, or wheat which have a high germination rate if the seed is simply laying on top the soil.

To increase the success I typically only broadcast soybeans right before or during a good rain (1/2″ or more).  The raindrops serve to insure there’s adequate soil moisture and splash some dirt on top the seeds.  A drag make out of chainlink fence, etc. can also be used in an effort to cover the bean seeds with a bit of dirt.  Drags tend to move seed and deposit them in low places, etc., so be careful using this technique.  Don’t use a drag make out of a railroad tie, etc., as seed almost always pile up in front of such pieces of equipment and then are deposited in low spots.  

Finally, I typically use at least 25% more seed when broadcasting compared to using a drill.  Almost always more seed will die due to being left on top the soil or be consumed by birds and rodents when it’s broadcast versus being placed at the appropriate depth by a drill.  

Many county NRCS offices rent drills for approximately $10 per acre.  I’ve rented many drills to establish food plots. It might be worth checking on the availability of a drill near you.

Enjoy creation,

grant