Ernst Conservation Seeds conditions and prepares seed to the highest standard and sells it in bulk or pure live seed (PLS) quantities. Seeding rates in this guide are based on bulk seed unless otherwise indicated. Sometimes professional or contractual seed mixes are expressed in PLS quantities to create a more exact quantity. PLS refers to the amount of live seed in a lot of bulk seed. The cost of pure live seed is proportionately higher than bulk seed.
The purity multiplied by the germination + dormant or hard divided by 100 = the of pure live seed (PLS) in a lot of bulk seed. To determine how much bulk seed is needed to equal 1 PLS lb, 1 is divided by the PLS %.
Example: 96% purity x 60% germination + 20% dormant or hard divided by 100 = 76.8 PLS in 1 bulk lb; 1 divided by .768 = 1.3. Therefore, 1.3 bulk lb of seed is equal to 1 PLS lb.