Seed Planning Zone (SPZ) geometry is comprised of geographic areas of the province that are characterized by common ecological and genetic attributes for a given forest tree species. SPZ's are used for seedlot registration, seed planning, seed transfer and seedlot selection for reforestation. The geometry can be joined to the SEED_PLAN_ZONE table using SEED_PLAN_ZONE_ID to determine if the SPZ is for Genetic Class B (natural stand) or Genetic Class A (orchard/parent tree) and tree species.

Seed Planning Unit (SPU) geometry is comprised of Seed Planning Zone geometry delineated by elevation ranges. Each SEED_PLAN_UNIT_ID relates to a SEED_PLAN_ZONE for a specific tree species and minimum/maximum elevation in meters. Seed Planning Units only apply to Genetic Class A (orchard/parent tree). Some coastal species also have a latitude range. The geometry can be joined to the SEED_PLAN_UNIT table using SEEED_PLAN_UNIT_ID to determine the Seed Planning Zone, tree species and elevation range.