Pittosporum Banks ex Gaertn.

In Australia and its territories, erect shrubs, or more usually trees, to 30 m high and 45 cm diam. d.b.h., heteroblastic, most functionally dioecious but never completely so. Short shoots present and sometimes spinescent (e.g. Pittosporum oreillyanum); hairs T-shaped or uniseriate, clear, white, red-purple or golden brown. Leaves variable depending on growth stage. Cotyledons mostly 2, opposite. Juvenile leaves with lamina margin variably toothed or lobed, rarely pungent (P. multiflorum only). Adult stage leaves clustered, alternate or whorled, upper surface glossy, green to yellow, lower surface generally paler; stipules absent.  Inflorescences mostly terminal, acrotonic or basitonic, paniculate to single-flowerd. Flowers campanulate, rotate or salverform, aromatic, with parts in 5s regularly placed around the pistil; male inflorescences more floriferous. Sepals mostly spreading and usually less than a third of petal length. Petals ligulate-spathulate, centrally cohering until anthesis or spreading, white-cream becoming yellower with age, rarely red, darkening with age (P. oreillyanum), sometimes bicoloured cream-red (P. bicolor). Stamens free, exserted in male flowers; anthers dorsifixed or basifixed or rarely versatile, always shorter than filaments, ovate to rectangular, dehiscing by apical slits, pollen usually yellow. Staminate flowers can appear perfect with a much-reduced, usually thin, spindle-shaped pistil. Pistil usually with a receptacle disc and basal nectary; ± stipitate; ovary  bi-(or rarely tri-)carpellate but appearing unilocular through the absent septum; placentation parietal, ranging from flat on walls to almost meeting in the centre, ovules inserted in 2 rows per loculus. Pistillate flowers with stigma well developed, prominent; stamens barely reaching to base of style, anthers very thin-sagittate, brownish, nil pollen. Fruit capsular, appearing unilocular, with mainly 2 or occasionally 3 valves in Australia (trivalved in New Zealand species), loculicidally dehiscent or indehiscent (Citriobatus group) or 'tardily' dehiscent; epicarp thin leathery and green-brown, or thick (rarely woody in Australia) and orange. Seeds glossy, red, orange or red-brown, chunky, not winged, packaged in a resinous mass for easy predation, the resin either thin and liquid or thick-coagulating.

Malaysian Pittosporums are generally small to at most medium-sized shrubs or trees from the substage of the rain-forest. They do not tend to be social or gregarious but none of them seems to be rare. Only two species are found in forests which are subject to a distinct dry season and that apparently only in part of their area, viz P. moluccanum in the mountain areas of Central and East Java and the Lesser Sunda Islands and P. ferrugineum which is also widely distributed and is the only species occurring in Javanese teak-forests. Both of them may be pioneering in open, grassy mountain forest; P. ferrugineum is, according to VAN DER PIJL ( VAN DER PIJL Ann. Jard. Bot. Btzg 48 1938 136, 138 ), a common pioneer on the lavas of Mt Guntur (W. Java); it has also been employed in re-afforestation work, according to KOORDERS. A similar position is occupied in the Philippines by P. pentandrum which is frequent in parang vegetation.As to altitude many species are rather tolerant; P. sinuatum and P. ramiflorum, for example, range from sea-level through the tropical and montane zones to the lower part of the subalpine zone up to respectively 2700 and 3200 m altitude. There are only two true mountain species, both endemic in New Guinea, viz 6. P. pullifolium (600-)1200-3800 m and 5. P. berberidoides 3000-3900 m. The former species exhibits in its leaves a certain vegetative adaptation towards high altitudes in getting thicker and smaller with recurving leaf margins and condensed habit in proportion to altitude. A similar behaviour is observed in P. ferrugineum, the high-altitude form of which was described as P. versteeghii.Several species have been observed to grow as epiphytes or hemi-epiphytes in tall forest but are also recorded as terrestrial shrubs in more exposed spots.The same species have occasionally been mentioned to be medium-sized trees. There is a possibility that these records are erroneous and that the epiphytic habit was overlooked, the size taken from that of the host tree. Collectors should check this in the field (cf. P. pullifolium)

Used in horticultural, including species imported from New Zealand (mainly Pittosporum eugenioides, P. tenuifolium) which are used for hedging and other foliage displays. Pittosporum crassifolium (New Zealand) and P. tobira (widespread in Asia) are particularly useful in heavily polluted areas such as inner city streetscapes. The species known to the Australian horticultural trade as the Queensland Pittosporum (P. rhombifolium) is the type species for genus Auranticarpa (Cayzer et al. 2000b). Pittosporum angustifolium (previously known by the misapplied name P. phillyreoides) is often grown by native plant enthusiasts, while P. undulatum (Sweet Pittosporum) is the most commonly grown of the Australian species but is now a declared weed on three continents including some parts of Australia where it is not native. A few species have a limited use in cabinetry.