Weekly Report

22 April 2022

City
Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Summary

High grass counts were recorded in Bloemfontein, with moderate grass pollen seen in Kimberley. Moderate fungal spore counts were recorded in Pretoria and Kimberley. No new data were available for Durban, but fungal spore levels are likely still high in that area.

Cape Town

Grasses were not significant. Tree levels are increasing as a wider variety of tree types were seen in the air. These include cypress (Cupressaceae), the sumac family (Anacardiaceae), waxberry (Morella sp.), white mulberry (Moraceae), the ebony family (Ebenaceae), gum (Myrtaceae), Australian pine (Casuarina sp.), karee (Rhus/Searsia sp.), forest elder (Nuxia sp.) and birch (Betula sp.). Weeds were low and the types detected were goosefoot (Chenopodiaceae), mugwort (Artemisia sp.), the daisy family (Asteraceae), sedges (Cyperaceae), ferns (Polypodiaceae) and erica (Ericaceae). Moulds were low.

Calvinia

All pollen categories and fungal spore counts were low. Tree pollen included the sumac family (Anacardiaceae) and waxberry (Morella sp.). The weed pollen types detected were mugwort (Artemisia sp.), the daisy family (Asteraceae), the cabbage family (Brassicaceae), goosefoot (Chenopodiaceae), the mallow family (Malvaceae) and erica (Ericaceae).

Johannesburg

Very low pollen and mould levels were seen across all categories. Tree pollen included the olive family (Oleaceae), oak (Quercus sp.), lindens (Tiliaceae) and elm (Ulmaceae). The weeds detected were mugwort (Artemisia sp.) and erica (Ericaceae).

Pretoria

Very little pollen was detected during this sampling period, but moulds increased in response to rain and moderate autumn temperatures. Tree pollen detected included cypress (Cupressaceae), ash (Fraxinus sp.) and Cape holly (Ilex sp.). Weeds identified included the daisy family (Asteraceae), goosefoot (Chenopodiaceae) and slangbos (Stoebe-type).

Bloemfontein

High grass counts were seen during this sampling period. Tree and weed pollen levels were low. The trees detected were the sumac family (Anacardiaceae), bushwillow (Combretaceae), waxberry (Morella sp.), gum (Myrtaceae) and pine (Pinaceae). Weeds included ice plants (Aizoaceae), mugwort (Artemisia sp.), the daisy family (Asteraceae), the carnation family (Caryophyllaceae), mallows (Malvaceae) and nettles (Urticaceae). Fungal spore counts were approaching significance, and included spikes for allergenic moulds.

Kimberley

Grasses were moderate, as rain reduced pollen in the air on some days of this sampling period. No tree pollen was detected but occasional weeds included ragweed (Ambrosia sp.), mugwort (Artemisia sp.) and goosefoot (Chenopodiaceae). Moulds were low.

Durban

Once more, courier delays meant no new data were available for this site, and the previous week is repeated. Moulds reached high levels as strong spikes were recorded for ascospores and basidiospores. Pollen in all three categories was insignificant. Tree pollen included cypress (Cupressaceae), waxberry (Morella sp.), gum (Myrtaceae), birch (Betulaceae), the sumac family (Anacardiaceae) and karee (Rhus/Searsia sp.). Weeds included ragweed (Ambrosia sp.), ferns (Polypodiaceae), the daisy family (Asteraceae), goosefoot (Chenopodiaceae), protea (Proteaceae), sedges (Cyperaceae) and nettles (Urticaceae).

Gqeberha

Extremely low counts were seen for pollen and fungal spores. No grass or tree pollen was detected and only slangbos (Stoebe-type) was recorded in the weeds category.