Rice hulls are the outer covering or husk of the rice kernel.
Rice hulls are mixed with seed to solve the following problems:
- To insure a more uniform coverage when seeding a mixture of different sized seeds.
Slow the Rate of Application
Many seed drills are designed to handle relatively large seeds such as barley, wheat and oats. Most seeds used in land revegetation are much smaller than these common field seeds. The drills that are designed to handle the larger sized seeds frequently have seeding openings that cannot be closed down far enough to slow the rate of smaller seeds. However, rice hulls can be added to the seed mixture to increase its bulk and thereby slow the rate that the seeds emerge from the drill. Rice hulls feed through a grain drill at the same rate as barley.
Prevent Bridging of Fluffy Seeds
The physical structure of certain seeds is fluffy. Fluffy seed has a tendency to bridge in the box of seed applicators. Adding rice hulls to the seed reduces the overall fluffiness of the seed thereby reducing its tendency to bridge.
How Are They Used?
Rice hulls are blended with seed to attain the desired application rate. Rice hulls weigh nine pounds per bushel. Use standard calibration techniques for determining the settings of your seeding equipment. For more information on calibration techniques refer to the following Calibrating a Seed Drill for Conservation Plantings Technical Notes from the Natural Resources Conservation Service.