Landraces are pure regional cultivars that adapted to specific geographies over hundreds of years without modern hybridization — Afghan, Hindu Kush, Thai, Colombian, Mexican, Malawi, Lebanese, Moroccan, Hawaiian.

They're the genetic root system of the entire modern catalog. Every commercial hybrid eventually traces back to landrace ancestry — Skunk #1 is Afghan × Acapulco Gold × Colombian Gold; Haze is Colombian × Mexican × Thai × South Indian.

Landraces are genetically diverse (heterozygous) — a 'landrace' is more accurately a regional population than a single uniform line. Two Hindu Kush plants from the same valley can express noticeably differently.

Preservation breeding centers on landraces because once a regional population is hybridized out or replaced by commercial lines, the original genetic substrate is gone. Pollination drift from imported genetics has been actively eroding landrace populations for decades.

Are landraces stable?+
More stable than F1 hybrids, less stable than IBLs. They're regional populations, not single lines.
Why preserve landraces?+
Once gone, the underlying genetic substrate is gone. Modern hybrids can't be recreated without landrace ancestors.