Table 5.1 A hierarchical classification and brief ecological description of the vegetation associations on Signal Hill, Cape Town

HISTORY AND DESCRIPTION OF CONTEMPORARY VEGETATION, SIGNAL HILL, CAPE TOWN
CHRISNA JOUBERT
Thesis submitted for the degree of Master of Science (Botany) at the University of Cape Town
April 1991

Communities on the Tygerberg Shale section of Signal Hill:

• 1 Rhus lucida - Chrysocoma coma-aurea community occupying the entire study area.
The most constant species are: Rhus lucida, Anthospermum spathulatum and Otholobium hirtum with a cover of 10-60%. The second stratum is dominated by the woody shrubs Chrysocoma coma-aurea, Helichrysum patulum, Salvia africana-caerulea, Rhus laevigata, Hermannia hyssopifolia and Senecio pterophorus, and the grass Merxmuellera stricta with a height of 0.25-1.0 m and a canopy cover of 10-25%.

• • 1 .1 Hyparrhenia hirta - Rhus glauca sub-community on N- and NW-facing seaward slopes and in dry ravines.
The mid-high sparse shrub stratum consists mainly of Rhus lucida, Anthospermum spathulatum and Otholobium hirtum. The open grassy/low shrub stratum is dominated by Rhus glauca and Hyparrhenia hirta. Other species are Protasparagus capensis, Hermannia alnifolia, H. prismatocarpa, Aspalathus ericifolia, A. cordata, A. cymbiformis and Sutherlandia frutescens. The sparse herbaceous component includes Ehrharta calycina and Tribolium hispidum.

• • • • 1 .1 .1 Variant of open grassy/low shrubland on hot and dry NW- and N-facing open slopes and in dry ravines with shallow soils. (Eragrostis curvula and Erepsia anceps present)
• • • • 1.1.2 Variant of open grassy/low shrubland on hot and dry north facing open slopes and in dry ravines with shallow soils. (Eragrostis curvula and Erepsia anceps absent)
• • • • 1.1.3 Variant of sparse grassy/low to mid-high open shrubland on mostly NW-facing open slopes and in valleys with shallow soils. This is the most extensive variant in the study area and covers some (48%) of the study area.

• • 1 .2 Cliffortia polygonifolia - Rhus tomentosa sub-community on E- and SSE-facing inland slopes and in valleys with shallow to deep soils.
The high constancy and canopy cover values of many species such as Rhus lucida, Chrysocoma coma-aurea, Helichrysum patulum, Cliffortia polygonifolia, Rhus tomentosa, Olea europaea subsp. africana, Chironia baccifera, Stoebe cinerea and Myrsine africana is typical.

• • • • 1 .2.1 Variant of mid-high open shrubland on E- and SE-facing open slopes with shallow to moderately deep soils.
• • • • 1.2.2 Variant of mid-high mid-dense shrubland in E- and SE-facing valleys with moderate to deep soils.

The study did not include the granites of Lions Head: so no Fynbos communities

The checklist is of the dominant and characteristic species of these communities.