sphaerocephalus, Boronia pilosa, Sprengelia incarnata, Restio complanatus and Calorophus 718111 elongatus are found in more sheltered parts and COASTAL HEATH probably "grade in" from the adjoining sedgeland/ heath. In protected bays and small inlets This land system stretches in a thin belt along vegetation similar to the heath flora occurs but the rocky coastline of the South West. It occurs is usually taller. Vegetation on is mainly along the west coast where inland plains similar to that described above. More protected are at a low altitude, in comparison to the south locations on De Witt Island are included in Land coast, where mountain ranges and high cliffs form System 817251. Detailed lists of vegetation on a discordant coastline. The land system covers various South West Islands can be found in White the Maatsuyker Group of islands except for a (1980). According to this author Senecio part of De Witt Island. It also covers the Breaksea spathulatus dominates large areas of Mutton Bird Islands, and part of Ile du Island while Poa poiformis is particularly common Golfe. Precambrian schist, quartzite and on Flat Witch Island. In addition to species listed conglomerate are the main rock types forming above Drimys lanceolata appears to be widespread rocky platforms, low rocky cliffs, deep gulches, in some heaths on the offshore islands (White occasional blowholes and small offshore islands 1980). and reefs. Grey clay loam or light clay gradational soils It is very exposed to westerly and south westerly cover most of and usually have winds which together with salt spray, and in some organic accumulation on the surface. Mica extreme cases wave action, restricts vegetation flecks and fine sand are common in most profiles. growth. As an ecological factor the affect of salt There is very little variation in soil texture across spray on vegetation has received very little the island which is probably a reflection of the attention in the South West. The most notable relatively homogeneous geology. This makes it features, which are similar to those described by an ideal place to investigate factors controlling Parsons and Gill (1968) for an area at Wilsons vegetation development which would mainly be Promontory, are growth to the landward side, effected by exposure, the presence or absence of canopy sloping up from the seaward side and sea bird burrows, sodium chloride toxicity and stunted growth forms. They also found that the slope stability. "... most important effect of salt spray on vegetation is the deposition of large amounts of Exposed slopes and those effected by mass salt on aerial plant parts, frequently causing the movement are densely covered by Tetratheca sp., death of shoots and leaves from chloride toxicity Senecio sp., Carpobroutus rossii, Poa poiformis, ... " and that salt spray populations often become and various herbs. This grades further upslope more succulent then their counterparts in sheltered into coastal heath with Leptospermum scoparium locations. Boyce (1954) suggests that (? var eximium), Westringia brevifolia, Correa asymmetrical growth forms and sloping crowns backhoasioma, Cyathodes juniperina, Olearia are not a result of wind-pruning but rather of phlogopapa, Drimys lanceolata and Pimelia sp. chloride toxicity, with chloride entry at sites of common. Vegetation stripes occur on the south mechanical abrasion to twigs and leaves on more west tip below the light house with the species exposed seaward aspects. In the most exposed described above forming the stripes and Poa spp. locations of this windswept land system wind occurring in between. Towards the north eastern pruning probably does occur. Possible evidence tip exposed edges near the top of gulches or cliff includes the shape of vegetation which develops edges have very little or no soil accumulation on the leeward side of minor rock outcrops and have a feldmark appearance, woodland immediately above the rocky wave swept covers most higher parts of the Island with platform. In cross section the plants are typically Leptospermum scoparium, Melaleuca squarrosa, mirror images of the small seaward outcrops, Cyathodes juniperina and Banksia marginata much the same as feldmark vegetation common common. Various ferns and mosses occur in the in subalpine and alpine areas. understorey and up the 'trunks' of woodland species. Soils are dominated by organic profiles with no B horizon although peaty gravels or sands may Nature conservation is the main land use in this occur beneath the peat. Even the most exposed land system but Maatsuyker Island is wave affected platforms and slopes tend to have Commonwealth land managed by the Department organic accumulations in small cracks and of Telecommunications. Salt spray limits crevices. This supports a sparse vegetation cover vegetation development at many sites and sheet with rock outcrop dominating. The coastal heath erosion will result if burning occurs. In this respect forms a belt behind the windswept rocky most of this land system is extremely vulnerable exposures and is characterised by the following as it is in very inaccessible areas where fires are species: Leptospermum scoparium var. eximium, difficult to prevent or combat. There is a high L. nitidum, Melaleuca squamea, Banksia landslip hazard resulting from wave action which marginata, Westringia brevifolia, Correct undercuts slopes. backhousiana, Persoonia muelleri, Exocarpos syrticola and Epacris impressa. Gymnoschoenus

66 LAND SYSTEM COASTAL HEATH

7 1 8 1 1 1 Area(ha): 4597

ALTITUDINAL 0-300 APROXIMATE ANNUAL RAINFALL (mm) RANGE (m) 1500-2000 SITE NO./ 174/15/W 175/20/W 183/15/- 181/2/N ALTITUDE(m) /ASPECT TOPOGRAPHY Rocky coastal platform and associated slopes and flats Position Rocky wave affected Exposed coastal slope Very exposed coastal Slopes in protected bays platform (on schist) slope (on conglomerate) Typical. 10-30 0-5 0-5 10 Slope(°) Proportion (%) 45 45 10

GEOLOGY Precambrian schist, and conglomerate quartzite NATIVE Sparse low vegetation Closed to open heath Closed to open-heath Closed to open-scrub VEGETATION cover - rode outcrop Structure dominates Floristic Leptospermum scoparium Melaleuca squamea Leptospermum scoparium Lertospermum Associatio var eximium Cyathodes Sprengelia incarnata var. eximiun L. nitidum nitidum L. n (See abietina Plantago Aotus ericoides Correa backhousiana qlaucescens Appendix 1 triantha Cakile Banksia marginata Sprengelia incamata Banksia for common edentula Stipa Leptospermum Westringia brevifolia marqinata names) teretifolia Poa glaucescens Persoonia muelleri Westringia poiformis Westringia Exocarpus syrticola Banksia marqinata brevifolia brevifolia Samolus Parsoonia muelleri Dillwynia glaberrima Cbrrea repens Epacris heteronema Leucopogon eriooides backhousiana Gymnoschoenus Leucopogon sphaerocephalus ericoides L. Restio complanatus parviflorus SOIL Black (5 YR 2. 5/1) CalorophusBlack (10 YRelongatus 2/1) Black (5 YR 2. 5/1) AcaciaBlack (7. 5 YR 2/0) fibrous Surface(A or sandy gritty fibrous fibrous peat over a very fibrous peat peat P peat in cracks and dark grey (10 YR 3/1) horizon)Colou crevices muck peat Subsoil (or B No B horizon Peaty gravels No B horizon Sandy B horizon likely in horizon) colour places (moist) and texture Primary Profile Organic Organic Organic Organic form Depth surface ) 0. 10 0. 55 0. 35 0. 50 horizon(m Typical total 0. 10 0. 55 0. 35 0. 50 depth(m) Permeability High High High High LAND USE Nature conservation HAZARD High sheet erosion if burnt frequently