Weekly Report

11 February 2022

City
Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Summary

A new monitoring site was added to the South African Pollen Monitoring Network: Calvinia in the Northern Cape. Grass and fungal spore counts were high in the summer rainfall areas, with Pretoria having the highest grass count in the country and the highest fungal spore levels were found in Kimberley. Tree and weed pollen levels were not significant at any of the sites.

Cape Town

The pollen counts for grasses, weeds and trees were not significant during this sampling period. Tree pollen included cypress (Cupressaceae), bushwillow (Combretaceae), the pea family (Fabaceae), gum (Myrtaceae), pine (Pinaceae), karee (Rhus/Searsia sp.) and elm (Ulmaceae). The weed pollen detected was bulrush (Typhaceae), goosefoot (Chenopodiaceae), erica (Ericaceae), plantain (Plantaginaceae), sorrel (Rumex sp.) and nettle (Urticaceae). Mould counts were also low.

Calvinia

Very few pollen grains were recorded during this late summer sampling period. Grass, tree and weed levels were not significant. Tree pollen included karee (Rhus/Searsia sp.) and the pea family (Fabaceae). The weeds identified were sedges (Cyperaceae), the mustard or cabbage family (Brassicaceae), goosefoot (Chenopodiaceae), nettles (Urticaceae) and the daisy family (Asteraceae). Moulds were found in low amounts.

Johannesburg

A technical issue was experienced at this site and the results from last week are repeated. Significant grass counts were seen, with low trees and weeds. Tree pollen included only Australian pine (Casuarina sp.) and Myrtaceae. The weed pollen detected were sedges (Cyperaceae), pigweed (Amaranthus sp.) and erica (Ericaceae). Fungal spore levels were low.

Pretoria

Grass pollen maintained high levels in the atmosphere. Tree and weed levels were insignificant. Trees detected were palm (Arecaceae), birch (Betulaceae), cypress (Cupressaceae), mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae) and plane (Platanus sp.). Weeds included goosefoot (Chenopodiaceae), sedges (Cyperaceae) and slangbos (Stoebe-type). Moulds breached the significant threshold and small spikes were noted for Cladosporium following rain.

Bloemfontein

Significant grass and fungal spore levels were detected, with low tree and weed counts. Trees included acacia (Acacia sp.), birch (Betulaceae), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), karee (Rhus/Searsia sp.) and elm (Ulmaceae). The weed pollen recorded was from the daisy family (Asteraceae), sedges (Cyperaceae), bulrush (Typhaceae), goosefoot (Chenopodiaceae), pelargoniums (Geraniaceae), plantain (Plantaginaceae) and nettles (Urticaceae).

Kimberley

Significant grass and fungal spore levels were detected, but tree and weed counts remained low. Only gum (Myrtaceae) was detected in the trees category, and weed pollen included the daisy family (Asteraceae), goosefoot (Chenopodiaceae), plantain (Plantaginaceae), fern spores (Polypodiaceae) and sedges (Cyperaceae).

Durban

Few pollen grains were trapped during this sampling period. Trees identified included karee (Rhus/Searsia sp.), pepper tree (Schinus sp.), mulberry (Moraceae), Australian pine (Casuarina sp.) and gum (Myrtaceae). Weeds detected were ragweed (Ambrosia sp.), ferns (Polypodiaceae), sedges (Cyperaceae), bulrush (Typhaceae), sorrel (Rumex sp.) and nettle (Urticaceae). Moulds were low.

Gqeberha

Tree, grass and weed pollen concentrations were low during this sampling period. Trees detected were Australian pine (Casuarina sp.) and gum (Myrtaceae). Weeds included pigweed (Amaranthus sp.), the daisy family (Asteraceae) and the carnation family (Caryophyllaceae). Moulds were low.