We pulled in at gate MH18, 50 metres from the summit of Mount Hayfield at the northern end of Mount Hayfield Road (off Springs Road, from Range Road). Through the pine plantations we could see flashes of sky and the brown paddocks stretching off to the north. It’s up in the highlands here, and where it’s not grazing land or forestry plantations, there’s still patches of native forest, the most significant of which is the Kalamunda Native Forest Reserve, part of the Second Valley Forest complex.
Continuing our research into the ecology of the Fleurieu, we’ve been looking for examples of what our own landscape might have looked like before clearing to help guide our regeneration efforts. Of the three local forest reserves, Kalamunda seemed like a good fit. Perched above Yankalilla, Kalamunda is a fragment of the kind of woodlands which were present across the Fleurieu.
As noted in the Forestry SA Management Plan, the Kalamunda and Springs Road Native Forest Reserves are among the few places on the Fleurieu Peninsula that weren’t intensively logged for timber. That said, Kalamunda is far from pristine wilderness. Evidence can be found of the harvesting of Yakka for explosives manufacture, and from the late 1800s onwards, larger trees were ring-barked in an effort to open the land for grazing. From the 1920s the woodland was regularly burnt in an effort to promote green pick for sheep, and through the 1940s it was the site for intensive sheep grazing, until 1983 when the pine plantations were established.
After a quick visit to the trig point at the summit of Mount Hayfield, a site of Kaurna cultural significance for its identification on the Tjilbruke Dreaming Track, we headed northwest along Mount Hayfield Road, and through the pine plantations to the Native Forest Reserve. As we’ve planted out our property, we’ve been fascinated to see how aspect and soil so significantly shape what grows where. On high, well-drained southerly aspects, we’ve found virtually everything thrives, with blackwoods reaching rapidly above their tree guards. In contrast, the north-facing strip along our front boundary rapidly dries out, with sporadic survival. It’s clear too that the woodland has its own micro-climates. it’s significantly cooler here than in our open paddocks just a few kilometres away, and in offering shelter and protection, woodland supports its own regeneration.
There’s a finger of pine plantation in the north-eastern corner of the reserve, and we follow the track along its northern edge. To our right is a steep, south-facing slope, dominated by stringybarks and dense with yakkas, to our left, on the north-facing slopes, the woodland is open, sinuous with pink gums and occasional native cherries and yakkas. A fallow deer, crashes through the dry growth, pauses to watch us, then bolts.
Acacia paradoxa occurs in both aspects, but on the sunny, northward slopes they’re substantial compared with their more modest scale between the yakkas and other plants on the south-faces. In damp, sheltered gullies and drainage lines there are swamp gums, blue gums and rough-barked manna gums and a thick carpet of bracken, with occasional appearances in pink gum country. At this time of year, and with our amateur botanists’ eyes, it’s hard to identify much vegetation: we spot some clumps of rushes (Juncus pallidus) among the pink gums, and weeds like African daisy are in flower (Senecio pterophorus), but the Forestry Management Plan contains comprehensive plant lists, together with identified birds, mammals, reptiles and amphibians.
Back on the farm, we see echoes of what’s happening at places like Kalamunda – after three years, some plants are unexpectedly thriving in the microclimates of the gullies, while many species are struggling in the open, exposed, north-facing slopes. We need to refine our planting selections in places like these, perhaps to reflect more of the cross-section of the northern slopes of Kalamunda. There’s perhaps also an element of time involved: perhaps establishing hardy, kangaroo-resistant Acacia paradoxa first would allow us to begin creating microclimates for sheoaks, and pink gums, which in turn create canopy and shelter for greater diversity beneath.