Summary
High grass pollen levels continue in the summer rainfall areas of South Africa, with very high counts seen in Kimberley. Tree counts increased in Pretoria due to a peak in gum tree pollen, but low tree and weed counts were seen in the rest of the country. Similarly, mould counts were low across all sites, except in Kimberley where warm and humid weather produced a spike in the allergenic spore, Cladosporium.
Cape Town
Moderate grass pollen counts with low tree and weed counts were seen. The tree pollen detected were cypress (Cupressaceae), waxberry (Myricaceae), gum (Myrtaceae), karee (Rhus/Searsia sp.) and pepper tree (Schinus sp.). Weeds included mugwort (Artemesia sp.), the daisy family (Asteraceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), bulrush (Typhaceae), plantain (Plantaginaceae), sorrel (Rumex sp.), fern spores (Polypodiaceae), dandelion (Taraxacum sp.) and nettles (Urticaceae). Mould counts were low.
Johannesburg
Tree, grass and weed pollen levels were insignificant during this sampling period. Trees detected were birch (Betulaceae), mulberry (Moraceae) and gum (Myrtaceae). Weeds included pigweed (Amaranthaceae), the daisy family (Asteraceae) and spurges (Euphorbiaceae). Moulds were low.
Pretoria
Significant grass levels were detected at this sampling site. Maize (Zea mays) was seen in low numbers. Trees detected were sumac (Anacardiaceae), palm (Arecaceae), birch (Betulaceae), mulberry (Moraceae), plane (Platanaceae) and gum (Myrtaceae). Weeds included pigweed (Amaranthaceae), the daisy family (Asteraceae), the carnation family (Caryophyllaceae) and slangbos (Stoebe-type). Moulds were low.
Bloemfontein
High grass levels were observed, while tree and weed pollen remained low. The trees recorded were hackberry (Celtis sp.), mulberry (Moraceae), waxberry (Myricaceae), gum (Myrtaceae), olive (Oleaceae), plane (Platanus sp.) and karee (Rhus/Searsia sp.). Weeds included sedges (Cyperaceae), the daisy family (Asteraceae), the carnation family (Caryophyllaceae), goosefoot (Chenopodiaceae), plantain (Plantaginaceae) and pigmyweeds (Crassula sp.) Fungal spore levels were low.
Kimberley
Significant grass levels were seen throughout this week. Trees and weeds were low. Trees detected included birch (Betulaceae), cypress (Cupressaceae), gum (Myrtaceae), bushwillow (Combretaceae), karee (Rhus/Searsia sp.) and olive (Oleaceae). The weeds found were goosefoot (Chenopodiaceae), the carnation family (Caryophyllaceae), bulrush (Typhaceae), sedges (Cyperaceae), the daisy family (Asteraceae), spurges (Euphorbiaceae), plantain (Plantaginaceae) and figworts (Scrophulariaceae). Mould counts were moderate due to a spike in the allergenic fungal spore, Cladosporium.
Durban
Pollen in all categories was insignificant. Trees detected were mulberry (Moraceae), karee (Rhus/Searsia sp.) and gum (Myrtaceae). Weeds included ragweed (Ambrosia sp.), goosefoot (Chenopodiaceae), the daisy family (Asteraceae), nettles (Urticaceae) and ferns (Polypodiaceae). Moulds were low on average, but high scores for ascospores were seen.
Gqeberha
Overall low pollen and fungal spore counts were seen in all categories. The tree pollen detected were Australian pine (Casuarina sp.), pine (Pinaceae) and olive (Oleaceae). Weed pollen included sedges (Cyperaceae), pigweed (Amaranthus sp.), katstert (Anthospermum sp.) and the carnation family (Caryophyllaceae).
