IntroductionPittosporum patulum is a small tree that grows up to six metres high, in sub-alpine scrub and mountain beech forest in the South Island.
The most striking aspect of Pittosporum patulum's appearance is the deep red, fragrant flowers that appear in springtime.
Unfortunately, little is known about the ecology of this species. However the population has definitely declined to the extent that it is classified as nationally endangered.
Where is it found?
Pittosporum patulum is 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. Juveniles have a single stem, with sparse branches and dark, narrow leaves that are toothed along the edges.
- 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 flowers during late spring and early summer. The flowers are dark red, cupshaped and very fragrant.
- The seeds are probably dispersed by birds but very little is known about how flowers are pollinated.
It is likely that Pittosporum patulum has always been a naturally uncommon species in our forests, with a special requirement for disturbance.
However, browsing by introduced mammals has caused the decline of this species and poses a major threat today. 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 seed in the litter beneath adult trees. Browsing insects also have the ability to deform new growth.
DOC's Pittosporum patulum Recovery Plan was approved in 1999. The plan sets in place a series of steps that will promote the recovery of P.patulum. It also outlines different management options, and a work plan.
The long-term vision of this plan is:'Self-sustaining populations of P.patulum to occur in the wild, throughout the natural range of the species.'
- mainly monitoring Pittosporum patulum populations, throughout various sites within the Nelson/Marlborough and Canterbury regions.
- yrees have been banded with aluminium bands and plastic pipe to protect them from possums and assess resilience.
- plants are being cultivated at several different nurseries.
- an enclosure has been constructed on Mount Patriarch in the Richmond Ranges. This plot will variously exclude possums, deer, goats and hares in order to determine the effects each species has on the trees.
You can help
DOC welcomes any comments or suggestions you may have about the conservation of Pittosporum patulum. Contact any DOC office.