Summary
The grass season is starting with high grass pollen counts detected in Cape Town (>20 grains/cubic meter). High tree pollen levels were also recorded in Cape Town and in Bloemfontein, with moderate tree counts seen in Johannesburg. Overall, the tree pollen counts have decreased at most sites across the country.
Cape Town
Grasses reached significant levels during this period. Tree levels remain high and allergenic levels were seen for plane (Platanaceae), oak (Quercus sp.), olive (Oleaceae), mulberry (Moraceae), pine (Pinaceae) and cypress. Cypress (Cupressaceae) tree concentrations were the highest. Other trees detected were karee (Rhus sp. / Searsia sp.), yellowwood (Podocarpaceae), gum (Myrtaceae), linden (Tiliaceae), elm (Ulmaceae) and poplar (Populaceae). Weeds were low and included protea (Proteaceae), the daisy family (Asteraceae), nettle (Urticaceae), the carrot family (Umbelliferae) and English plantain (Plantaginaceae). Moulds were low.
Johannesburg
Moderate tree counts and low weed counts were recorded. Ash (Fraxinus sp.), mulberry (Moraceae), plane (Platanus sp.) and birch (Betulaceae) were the most dominant tree pollens, and lower levels of acacia (Acacia sp.), bushwillow (Combretaceae), cypress (Cupressaceae), Australian pine (Casuarina sp.), hackberry (Celtis sp.), gum (Myrtaceae), pine (Pinaceae), poplar (Populus sp.), oak (Quercus sp.) and linden (Tiliaceae) were seen. The weed pollen detected were the daisy family (Asteraceae), the carnation family (Caryophyllaceae), goosefoot (Chenopodiaceae), erica (Ericaceae), spurges (Euphorbiaceae) and fern spores (Polypodiaceae). No grass pollen was detected and mould / fungal spore counts were low.
Pretoria
Grass, tree, weed and mould counts were low during this sampling period. Tree pollen included birch (Betulaceae), acacia (Acacia sp.), hackberry (Celtis sp.), cypress (Cupressaceae), bushwillow (Combretaceae), ash (Fraxinus sp.), jacaranda (Jacaranda sp.), gum (Myrtaceae), mulberry (Moraceae), pine (Pinaceae), yellowwood (Podocarpus sp.), poplar (Populus sp.), plane (Platanus sp.) and oak (Quercus sp.). The weed pollen detected were the cabbage family (Brassicaceae), the carnation family (Caryophyllaceae), goosefoot (Chenopodiaceae), spurges (Euphorbiaceae), English plantain (Plantago sp.) and pigmyweeds (Crassula-type).
Bloemfontein
High tree counts and low grass and weed counts were recorded. The dominant tree pollen types were mulberry (Moraceae) and waxberry (Morella sp.), with lower levels of pine (Pinus sp.) karee (Searsia sp. / Rhus sp.), olive (Oleaceae) and plane (Platanus sp.) seen. The daisy family (Asteraceae) and pigmyweeds (Crassula sp.) were the only weed pollen detected. Mould levels were low.
Kimberley
Grass, tree, weed and mould levels were low during this sampling period. Tree pollen included hackberry (Celtis sp.), mulberry (Moraceae), cypress (Cupressaceae), the sumac family (Anacardiaceae), birch (Betulaceae), olive (Oleaceae), bushwillow (Combretaceae), gum (Myrtaceae), pine (Pinaceae), yellowwood (Podocarpaceae), plane (Platanus sp.), poplar (Populus sp.), oak (Quercus sp.) and pollen from the pea family (Fabaceae). The weed pollen detected were aloes (Asphodelaceae), the daisy family (Asteraceae), sedges (Cyperaceae), the carnation family (Caryophyllaceae), goosefoot (Chenopodiaceae), erica (Ericaceae), mallows (Malvaceae), pellitory-of-the-wall (Parietaria sp.), nettles (Urticaceae), mezerium (Thymelaeaceae) and knotweed (Polygonaceae).
Durban
Grass, tree, weed and mould levels were low. Tree pollen included birch (Betula sp.), the sumac family (Anacardiaceae), cypress (Cupressaceae), mulberry (Moraceae), plane (Platanaceae), pine (Pinaceae), Australian pine (Casuarina sp.), cedar (Cedrus sp.), hackberry (Celtis sp.), the pea family (Fabaceae), bushwillow (Combretaceae), gum (Myrtaceae), syringa (Melia sp.), yellowwood (Podocarpaceae) and oak (Quercus sp.). The weed pollen detected were ice plants (Aizoaceae), the daisy family (Asteraceae) erica (Ericaceae), English plantain (Plantago sp.), goosefoot (Chenopodiaceae), spurges (Euphorbia sp.), fern spores (Polypodiaceae), sedges (Cyperaceae), knotweed (Polygonaceae), sorrel (Rumex sp.), pellitory-of-the-wall (Parietaria sp.), protea (Proteaceae) and nettles (Urticaceae).
Gqeberha
Grass, tree, weed and mould levels were all low during this week. Trees included acacia (Acacia sp.), the sumac family (Anacardiaceae), cedar (Cedrus sp.), cypress (Cupressaceae), waxberry (Morella sp.), olive (Oleaceae) and pine (Pinaceae). The weeds detected were sedges (Cyperaceae), the daisy family (Asteraceae), katstert (Anthospermum sp.), the carnation family (Caryophyllaceae) and erica/heather (Ericaceae).