Brunia paleacea, resprouter solution of the space problem

    Brunia paleacea, resprouter solution of the space problem
    Author: Ivan Lätti
    Photographer: Judd Kirkel Welwitch

    The whitish to cream of the bracts on the prickly Brunia paleacea flowerheads breaks the fynbos green. The cream-coloured florets are shorter, positioned lower than their bracts in the head. The florets are tiny, densely massed together, about 30 of them in each globular head. The heads, about 7 mm in diameter, grow in clusters on branched shoots from stem-tips. 

    These plants resprout after fire from the little stump or lignotuber remaining among the ashes. Importantly, the stumps are fully or mostly underground, surviving the burning of the mountainside. The resprouting, woody part not consumed by the fire brought about the common plant name of bergstompie. All resprouters benefit from woody underground stumps protected in the earth when the above-ground plant parts succumb to the flames. During or before the next winter's rainy season the intact root system sprouts young stems, much faster than single-stem reseeder shrubs can grow from scratch, i.e. from seed.

    This causes flowers and fruits to appear more promptly on resprouters, a few seasons before reseeders in the new veld. They feed all sorts of animals, from mammals to insects that can't wait years to be fed. This allows for a time-share system in fynbos: annuals from seed with rain, bulbs from underground resources suddenly rid of tall, dark, dominant bushes covering them, and resprouters from stumps flourishing in the first spring after fire.

    Following upon this, the competition for space and sunlight gradually becomes fiercer every season until the tall and spreading shrubs rule the roost again. The small species are pushed into submission, their cyclic long waits ensue until liberated by the next fire. Resprouters win during the first few seasons after fire, reseeders take their time but catch up, and overwhelm the opposition for a quick or leisurely season of peak performance, followed by rest and biding their time yet again. 

    And then it all starts again from lightning, or from humans who may cause veld fires too often. Prometheus should have stolen fire for the people only once they had grown up to handle it responsibly! In the growth-regulated fynbos burning cycle more resident species are enabled by evolution to do their reproductive thing, taking turns on the same land than could live there simultaneously while all fully active. 

    So, timeshare has been flourishing in fynbos and some other veld long before city people invented such systems. The perpetual struggle for Lebensraum among the living happens via fire or war, but people can learn... one day, maybe (Manning, 2007; Bean and Johns, 2005; iNaturalist).

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