G ranks

The relative imperilment of species on a global level as determined by NatureServe.

• G1 – Critically imperiled. At high risk of extinction because of extreme rarity.
• G2 – Imperiled. At high risk of extinction because of very restricted range.
• G3 – Vulnerable. At moderate risk of extinction.
• G4 – Apparently secure. Uncommon, but not rare.
• G5 – Secure. Widespread, common and abundant.
• **Clarification needed: would we apply seed zones for plants in G3?