Weekly Report

22 July 2022

City
Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Summary

Tree counts are increasing at some sites, with high counts detected in Johannesburg and moderate levels seen in Cape Town, Pretoria and Bloemfontein. Weed counts were moderate in Calvinia and moderate fungal spore counts were recorded in Cape Town.

Cape Town

Moderate tree counts included spikes in cedar (Cedrus sp.) and gum (Myrtaceae) pollen, with lower levels of the sumac family (Anacardiaceae), cypress (Cupressaceae), mulberry (Moraceae) and olive (Oleaceae) present. Weeds were low and included only sorrel (Rumex sp.) and nettles (Urticaceae). Fungal spore counts were moderate and grass pollen was low.

Calvinia

Moderate weed counts were seen due to a spike in nettle pollen (Urticaceae). Other weeds found included the daisy family (Asteraceae), goosefoot (Chenopodiaceae) and the carnation family (Caryophyllaceae). Grass, tree and fungal spore counts were low. The tree pollen detected was the sumac family (Anacardiaceae) and cypress (Cupressaceae).

Johannesburg

High cypress (Cupressaceae) counts were recorded in the trees category, with lower levels of acacia (Acacia sp.), the sumac family (Anacardiaceae), palm (Arecaceae), birch (Betulaceae), Australian pine (Casuarina sp.), mulberry (Moraceae), yellowwood (Podocarpaceae), oak (Quercus sp.) and elm (Ulmaceae) also present. Grass, weed and mould counts were low. The weeds detected included only sedges (Cyperaceae) and fern spores (Polypodiaceae).

Pretoria

Grass and weed pollen levels were low. Tree pollen was moderate and included birch (Betulaceae), cypress (Cupressaceae), pine (Pinaceae), plane (Platanus sp.), oak (Quercus sp.) and karee (Rhus/Searsia sp.). The weeds recorded were the daisy family (Asteraceae), the carnation family (Caryophyllaceae), goosefoot (Chenopodiaceae), erica (Ericaceae), rushes (Juncus sp.) and fern spores (Polypodiaceae). Mould counts were low.

Bloemfontein

Grass and weed pollen levels were low at this site but small spikes appeared for trees, especially poplar (Populaceae) on warm days. Other tree pollen detected included cypress (Cupressaceae) and karee (Rhus/Searsia sp.). Weed pollen included mugwort (Artemisia sp.) and the daisy family (Asteraceae). Mould spores were low.

Kimberley

All pollen types were low during this cold midwinter period. Trees identified included the sumac family (Anacardiaceae), cypress (Cupressaceae), karee (Rhus/Searsia sp.) and poplar (Populaceae). Weeds detected were goosefoot (Chenopodiaceae), mugwort (Artemisia sp.), the daisy family (Asteraceae) and rockfoils (Saxifrage sp.). Fungal spores were very low.

Durban

Low levels of pollen in all categories were seen during this sampling period. Tree pollen detected was karee (Rhus/Searsia sp.), poplar (Populaceae), cypress ((Cupressaceae), the sumac family (Anacardiaceae), mulberry (Moraceae) and Australian pine (Casuarina sp.). Weeds included the daisy family (Asteraceae), slangbos (Stoebe-type) and nettles (Urticaceae). Mould spores were very low.

Gqeberha

Low grass counts were seen. Low tree loads included cedar (Cedrus sp.), waxberry (Morella sp.), gum (Myrtaceae), pine (Pinaceae) and olive (Oleaceae). Weeds were low and included katstert (Anthospermum sp.), mugwort (Artemisia sp.), the daisy family (Asteraceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), erica (Ericaceae) and slangbos (Stoebe-type). Moulds were also low.