New Zealand Journal of Botany abstracts

---

Distribution of native forest in the upper Clutha district, Otago, New Zealand

PETER WARDLE

Landcare Research
P.O. Box 69
Lincoln, New Zealand

Abstract  The upper Clutha district extends from steep, glaciated mountains along the South Island Main Divide to broad plateaus and terraced valleys further downstream, and covers an annual precipitation gradient from 4000 mm to 400 mm. Tall forest prevails from the valley floors to the subalpine tree limit in north-western headwaters, but southwards down the rainfall gradient becomes increasingly confined to small pockets. Nothofagus is overwhelmingly dominant, with N. menziesii prevailing in the north-west and N. solandri var. cliffortioides in drier country to the east. Pockets of forest in the south of the district can consist of either species. Nothofagus fusca co-dominates with the other Nothofagus species at low altitudes through part of the Matukituki catchment, and over a small area by Lake Hawea. Low-altitude N. menziesii forest in the Makarora Valley has a similar composition to forests west of the Main Divide, and includes several conifer species and a wide range of broad-leaved trees, notably Weinmannia racemosa. The hardiest conifers, Podocarpus hallii and Phyllocladus alpinus, are widely distributed in the Nothofagus forests of the district and also dominate small stands of native trees on otherwise treeless mountains. In the moister part of the district Kunzea ericoides and Leptospermum scoparium are successional to broad-leaved forest, whereas in the drier parts they are self-perpetuating. Grey scrub, dominated mainly by Discaria toumatou, is widespread on slopes where rainfall is low, and on river flats under higher rainfall. Small trees of Sophora microphylla and Olearia spp. occur locally in this scrub.

Keywords  forest distribution; Nothofagus; Phyllocladus alpinus; Podocarpus hallii; precipitation gradient

B00021
Received 22 June 2000; accepted 22 May 2001

New Zealand Journal of Botany, 2001, Vol. 39: 435-446

0028-825X/01/3903-0435 $7.00 (c) The Royal Society of New Zealand 2001

PDF file of entire paper: medium quality (7907K); (scanned from paper original: notes about this process)

---

This year's abstracts | Journal home page | All abstracts | Publishing home page