Summary
Grass pollen increased to moderate levels in Pretoria, Kimberley and Potchefstroom. Most grass pollen was released in the cooler mornings in Kimberley as the maximum temperatures reached 40ºC, inhibiting pollen release. Tree pollen was moderate in Bloemfontein and ragweed was detected in Potchefstroom. Mould spores reached high concentrations in Durban.
Cape Town
Heavy rain followed by cool windy weather, resulted in a sharp decrease in mould spores. Tree, grass and weed pollen levels were low. Trees included gum (Myrtaceae), elm (Ulmaceae), walnut (Juglandaceae) and pine (Pinaceae). The only weed detected was goosefoot (Chenopodiaceae).
Calvinia
Pollen concentrations were very low in this hot, dry, Northern Cape town. Tree pollen types detected were elm (Ulmaceae) and olive (Oleaceae). Weeds were the daisy family (Asteraceae) and goosefoot (Chenopodiaceae and moulds were low.
Johannesburg
Tree, grass and weed pollen concentrations were low at this site. Trees detected included birch (Betulaceae), Australian pine (Casuarina spp.), karee (Rhus/Searsia spp.), elm (Ulmaceae) and pine (Pinaceae). Weeds were pigweed (Amaranthaceae), mugwort (Artemisia spp.), the daisy family (Asteraceae) and sedge (Cyperaceae). Mould concentrations were low.
Pretoria
Grasses were moderate. Trees were low but small spikes are noted for mulberry (Moraceae). Other trees were birch (Betulaceae), bushwillow (Combretaceae), cypress (Cupressaceae), gum (Myrtaceae), karee (Rhus/Searsia spp.) and poplar (Populaceae). Weeds were the daisy family (Asteraceae), goosefoot (Chenopodiaceae), rush (Juncaceae) and ferns (Polypodiaceae). Moulds were moderate with spikes for ascospores, basidiospores and Aspergillus/Penicillium.
Bloemfontein
Trees increased to moderate concentrations at this site. Trees detected were acacia (Acacia spp.), birch (Betulaceae), mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), poplar (Populacedae), karee (Rhus/Searsia) and elm (Ulmaceae). A low weed presence included the daisy family (Asteraceae), pigmyweeds (Crassulaceae), sedges (Cyperaceae) and erica (Ericaceae). Moulds were low.
Kimberley
Grasses increased to moderate levels during this sampling period. Low tree concentrations included elm (Ulmaceae), peppertree (Schinus spp.), waxberry (Morella spp.), walnut (Juglanaceae), poplar (Populaceae) and olive (Oleaceae). Weed concentrations were low and included the daisy family (Asteraceae), goosefoot (Chenopodiaceae) and spurges (Euphorbiaceae). Moulds were low.
Durban
Grasses were low but small spikes on some days were noted. Low tree pollen concentrations included cypress (Cupressaceae), mulberry (Moracreae), waxberry (Morella spp.), gum (Myrtaceae), elm (Ulmaceae), walnut (Juglandaceae) and poplar (Populaceae). Weeds were the dasiy family (Asteraceae), nettles (Urticaceae), mallows (Malvaceae), buckwheat (Polygonaceae), mezereum (Thymelaeaceae) and ferns (Polypodiaceae). Moulds were high.
Gqeberha
Tree, grass and weed pollen concentrations were low at this site. Trees detected were waxberry (Morella spp.) and gum (Myrtaceae). Weeds were katstert (Anthospermum spp.), mugwort (Artemisia spp.), sedge (Cyperaceae), lily (Liliaceae) and reeds (Restionaceae). Mould concentrations were similarly low.
Potchefstroom
Grasses increased to moderate levels. Tree concentrations were low and included Australian pine (Casuarina spp.), gum (Myrtaceae), oak (Quercus spp.), mulberry (Moraceae), cypress (Cupressaceae) and pine (Pinaceae). A low presence of weeds in the atmosphere included pigweed (Amaranthaceae), ragweed (Ambrosia spp.), the daisy family (Asteraceae), sedge (Cyperaceae), plantain (Plantaginaceae), nettle (Urticaceae) and the daisy or celery family (Umbelliferae). Mould concentrations were low.
