Eucalyptus citriodora. Citronella-scented leaves when crushed. The essential oil from this plant is an effective mosquito repellent frequently used in "natural" repellents.
Acacia farnesiana. Small flowering tree that is used in France in the perfume industry. Profusely flowering- especially in winter. Interesting twig structure with small thorns. Extremely drought tolerant once established. Some parts of the plant are used as food and for medicines.