A friend of mine received several packages of ornamental grass seeds today in the mail. Several of the packages are labeled by their name followed by "RUBBED SD". Does anyone know what this statement means?
It could mean the seed was cleaned by rubbing it (usually between two sheets of rubber) and then separated from chaff with a South Dakota (SD) Seed Blower.
It could just be an abbreviation for seed, as in Rubbed Seed. Rubbing before winnowing is a common practice.