Celmisia

Abstract: Summary Autumn initiation and successful overwintering of floral primordia are described for all 18 families and for 81 of the 100 alpine species examined. The high incidence of this phenomenon is not unexpected in view of its adaptive value and its widespread occurrence in alpine floras of the Northern Hemisphere. The causes of irregular flowering in alpine species of Aciphylla, Celmisia, and Chionochloa are discussed. A low-temperature requirement apparently prevents pre-winter opening of the fully developed buds in Caltha.

Abstract: Analyses of ITS sequences for 49 species of Olearia, including representatives from all currently recognised intergeneric sections, and 43 species from 23 other genera of Astereae, rooted on eight sequences from Anthemideae, provide no support for the monophyly of this large and morphologically diverse Australasian genus. Eighteen separate lineages of Olearia are recognised, including seven robust groups. Three of these groups and another eight species are placed within a primary clade incorporating representatives of Achnophora, Aster, Brachyscome, Calotis, Camptacra, Erigeron, Felicia, Grangea, Kippistia, Lagenifera, Minuria, Oritrophium, Peripleura, Podocoma, Remya, Solidago, Tetramolopium and Vittadinia. The remaining four groups and three individual species lie within a sister clade that also includes Celmisia, Chiliotrichum, Damnamenia, Pleurophyllum and Pachystegia. Relationships within each primary clade are poorly resolved. There is some congruence between this molecular estimate of the phylogeny and the distribution of types of abaxial leaf-hair, which is the basis of the present sectional classification of Olearia, but all states appear to have arisen more than once within the tribe. It is concluded that those species placed within the second primary clade should be removed from the genus, but the extent to which species placed within the first primary clade constitute a monophyletic group can only be resolved with further sequence data.

Abstract: The fires of January 2003 burnt much of the treeless high mountain country of Victoria, New South Wales and the Australian Capital Territory, and were the first extensive conflagration of this area since 1939. For this reason there are remarkably few studies of the response of alpine plants and vegetation to fire. A flora survey of treeless subalpine vegetation in the Kosciuszko area in late 2002 sampled 215 sites. Of the 119 sites that were burnt, 60 were relocated and re-sampled in late 2003 to assess the mode and extent of regeneration in a range of treeless plant communities. Twenty-four species (including 3 exotics) were recorded only in the pre-fire sampling. Fifty species (including 18 exotics) were recorded only in the post-fire sampling. One species, Chenopodium erosum, had not previously been recorded in Kosciuszko National Park, and is believed to be the first native chenopod recorded in alpine vegetation in Australia. There was no significant difference in mean number of species per quadrat between pre-fire and post-fire quadrats. The average number of weeds per quadrat was, however, significantly greater post-fire. Most of this difference was attributable to the significantly greater number of weeds per quadrat in bog vegetation after the fire. Of the 290 species recorded, 111 species regenerated from seed, 197 species regenerated from resprouting organs (roots, tubers and/or basal stems) and 49 species regenerated from both seed and resprouts. Based on the regeneration observed, most plant communities will return naturally to their pre-fire species composition and cover over a period between a few years and a few decades. Major exceptions will be those communities where the 'keystone' species appear to have been lost at least at a local scale. Principal amongst these are bog communities that incorporated significant biomass of Sphagnum cristatum pre-fire, Podocarpus lawrencei shrublands and Celmisia costiniana closed herbfields. Consideration might be given to augmenting their recovery. It will be important to exclude fire from these communities until their recovery is complete.

Abstract: In the drier mountains of the eastern and north-eastern regions of the South Island of New Zealand, there occurs very commonly a type of scree inhabited by a community of plants rarely found in any other situation. Although belonging to several different families, these plants have many characters, in common which distinguish them from plants of other alpine associations. This paper deals mainly with observations made on a large scree near the Canterbury University College Mountain Biological Station at Cass, 70 miles inland on the midland railway from Christchurch, New Zealand. This particular scree forms the northern slope, from 3000 to 6000 ft. above sea-level, of Mount Bailey, the northernmost peak of the Craigieburn Range not far from the main ranges of the Southern Alps (P1. 13, phot. 1). During the summer in this region, fine days are common, and while the brilliant sunlight of the high clear atmosphere raises the stony surfaces of the screes to a temperature such that they are unbearable to touch, blustering hot dry winds frequently sweep across the slopes from the west. In winter, snow may cover the ground for several weeks at a time. The annual rainfall of the district is 50 in., distributed fairly evenly throughout the year. The vegetation of the region consists of a tussock grassland association dominated by Poa caespitosa and Festuca novae-zealandiae, modified in local areas by variations in conditions. In sheltered situations small stands of beech (Nothofagus cliffortioides) replace the tussocks, while a shrubland association (Cassinia fulvida, Discaria toumatou, Leptospermum scoparium, etc.) occurs in many exposed places. At higher altitudes (above 3500 ft.) the short-tussock association (Poa-Festuca) gives way to a narrow belt of the tall-tussock, Danthonia raoulii, which forms the uppermost border of the grassland vegetation. Other high-mountain plants are found on rocks and in other stable situations above this altitude, usually including species of Hebe and Celmisia. Around the edges of the screes several small-leaved shrubs are the first unspecialized plants to enter the partially stabilized debris, e.g. Podocarpus nivalis and various members of the Epacridaceae, including species of Dracophyllum. Vegetation of screes outside New Zealand appears to be of two kinds. On very unstable soils certain specialized plants sometimes occur, which can survive movements of the surrounding stones. On slightly less mobile soils, plants are recruited from the surrounding stable soil associations of heath or rock. Such vegetation is often in a state of flux, since large areas may be buried by scree movements (Schroeter, 1926; Harshberger, 1929; Tansley, 1939). Very few papers dealing with the ecology of unstable screes appear to have been published, and those dealing with screes in Britain, Europe and America are mainly concerned with the successive phases of vegetation as consolidation takes place