Weekly Report

25 March 2022

City
Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Summary

Grass counts were significant in Pretoria and Bloemfontein. Tree and weed counts were low across the country, except in Cape Town and Durban where tree levels were moderate. Durban had very high fungal spore levels, with counts in Bloemfontein also approaching significance.

Cape Town

Grass and weed pollen counts were low, with tree pollen levels approaching significance. Trees found included the sumac family (Anacardiaceae), birch (Betulaceae), cypress (Cupressaceae), ash (Fraxinus sp.), waxberry (Myricaceae), gum (Myrtaceae), pine (Pinaceae) poplar (Populus sp.) and karee (Rhus/Searsia sp.). In the weeds category, the daisy family (Asteraceae), goosefoot (Chenopodiaceae), erica (Ericaceae), plantain (Plantaginaceae), buckwheat (Polygonaceae), figworts (Scrophulariaceae) and nettles (Urticaceae) were seen. Fungal spore levels were low.

Calvinia

No new data were available due to courier delays. The results from the previous sampling period are repeated. Grass, tree and weed pollen levels were low during this sampling period. The only tree detected was gum (Myrtaceae). Weeds included the daisy family (Asteraceae), goosefoot (Chenopodiaceae) and sorrel (Rumex sp.). Moulds were very low.

Johannesburg

All pollen categories as well as fungal spore counts were low. Australian pine (Casuarina sp.), hackberry (Celtis sp.), mulberry (Moraceae), pine (Pinaceae), oak (Quercus sp.) and elm (Ulmaceae) were detected in the tree pollen category. Weeds included pigweeds (Amaranthus sp.), sedges (Cyperaceae), erica (Ericaceae) and fern spores (Polypodiaceae).

Pretoria

Grass counts approached significance, but tree and weed levels were low. Tree pollen included acacia (Acacia sp.), birch (Betulaceae), cypress (Cupressaceae), mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae) and oak (Quercus sp.) Weeds detected were the daisy family (Asteraceae), the carnation family (Caryophyllaceae), goosefoot (Chenopodiaceae), erica (Ericaceae), spurges (Euphorbiaceae) and ferns (Polypodiaceae). Mould levels were low.

Bloemfontein

Significant grass and fungal spore counts, with low tree and weed pollen levels were seen during this sampling period. Tree pollen included bushwillow (Combretaceae), ash (Fraxinus sp.), waxberry (Morella sp.), gum (Myrtaceae), pine (Pinaceae), yellowwood (Podocarpaceae) and elm (Ulmaceae). The weed pollen detected were mugwort (Artemisia sp.), the daisy family (Asteraceae), goosefoot (Chenopodiaceae), the carnation family (Caryophyllaceae), plantain (Plantaginaceae) and nettles (Urticaceae).

Kimberley

Grass, tree and weed pollen was low. Tree pollen detected was ash (Fraxinus sp.) and weed pollen was sedge (Cyperaceae). Moulds were low but small spikes for the allergenic fungal spore, Cladosporium, were seen on some days.

Durban

Trees detected were ash (Fraxinus sp.), white mulberry (Moraceae), waxberry (Morella sp.) and gum (Myrtaceae). Weeds included the daisy family (Asteraceae), ragweed (Ambrosia sp.), sedges (Cyperaceae), nettles (Urticaceae) and ferns (Polypodiaceae). Moulds were high as ascospore levels soared and spikes were seen for basidiospores (mushroom spores) on occasion.

Gqeberha

All pollen categories as well as fungal spore counts were very low. Australian pine (Casuarina sp.) and waxberry (Myricaceae) were detected in the trees category. Weeds included only goosefoot (Chenopodiaceae) and slangbos (Stoebe-type).