Pittosporum patulum (Pitpat)
Species: P. patulum
Binomial name: Pittosporum patulum
Common name: Pitpat
Pittosporum patulum a small (>6m) naturally uncommon tree found only in the eastern South Island, occurring in northwest Nelson and sporadically from inland Marlborough to Wanaka. It occurs in sub-alpine scrub and in canopy gaps of mountain beech forest above 800 metres. It is sometimes locally common as a juvenile in the understory and occasionally forms a small tree in the sub-canopy. Most adult plants are found at open sites– avalanche terrain, river margins, on bluffs or above the tree line.
Pittosporum patulum is notable for having distinctly different juvenile and adult stages of growth (heteroblasty). Juveniles have a single stem, with sparse branches and dark, narrow leaves that are toothed along the edges.
The adults are small trees, with whitish-grey smooth bark, many spreading branches at their tops, and leaves that are shorter, broader and less toothed than juveniles.
Adult trees produce very fragrant deep red cup shaped flowers during late spring and early summer. The seeds are probably dispersed by birds but very little is known about how flowers are pollinated.
Pittosporum patulum is in decline is due to browsing by introduced mammals. Possums in particular appear to target adult plants, causing severe canopy defoliation and death, which is likely to be the reason why so few adults remain in most populations today. Deer and goats also contribute to the decline of this species by browsing saplings and seedlings. Rodents are known to eat Pittosporum patulum seeds in the litter beneath adult trees. Browsing insects also have the ability to deform new growth.
Photographed is the Temple catchment (near Lake Ohau).