They're tough. Equipped to handle drought, sub-zero temperatures, frost and even fire, olive trees are extraordinarily resilient. Their roots are so strong that they can re-grow even when it seems like they've been totally decimated.Olive cultivars may be used primarily for oil, eating, or both. Olives cultivated for consumption are generally referred to as "table olives". About 80% of all harvested olives are turned into oil, while about 20% are used as table olives.