Melaleuca alternifolia. Native to Australia, Tea Tree is an evergreen standing at 6 to 10 meters tall with highly scented leaves. It owes its name to Thomas Cook, who discovered the tea when he arrived in Australia. He made tea from the leaves and saw indigenous people making poultices with them to treat sores and infections. Today, Tea Tree essential oil remains a gold standard in family pharmacies for its antiseptic, antibacterial and germ-fighting properties.