Weekly Report

13 January 2023

City
Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Summary

High grass counts were recorded in Johannesburg, with moderate levels of trees and weeds at this site. Similarly, trees and weeds were moderate in Cape Town. Low pollen counts were recorded in Bloemfontein and Gqeberha, with no new data available in Calvinia, Pretoria, Kimberley and Potchefstroom. The fungal spore count in Durban was significant.

Cape Town

Low grass counts with moderate tree and weed counts were recorded. Trees detected included cypress (Cupressaceae), gum (Myrtaceae), pepper tree (Schinus spp.), birch (Betulaceae), bushwillow (Combretaceae), mulberry (Moraceae), olive (Oleaceae), pine (Pinaceae), karee (Rhus/Searsia sp.) and lindens (Tiliaceae). Weeds were goosefoot (Chenopodiaceae), the daisy family (Asteraceae), mezereum (Thymelaeaceae), erica (Ericaceae), sedges (Cyperaceae), plantain (Plantaginaceae), bulrush (Typhaceae), nettles (Urticaceae, and caltrops (Zygophyllaceae). Fungal spores were low.

Calvinia

No new data were available due to courier delays, so last week’s results are repeated. Pollen in all categories: Trees, grasses and weeds were scanty during this sampling period. Trees detected included bushwillow Combretaceae) and weeds were goosefoot (Chenopodiaceae), ragweed (Ambrosia spp.), knotweed (Persicaria spp.) and mezereum (Thymelaeaceae). Moulds were very low.

Johannesburg

High grass counts with moderate tree and weed counts were recorded. The trees detected were birch (Betulaceae), gum (Myrtaceae), olive (Oleaceae), and tamboti (Spirostachys sp.). Weeds included pigweed (Amaranthus sp.), the daisy family (Asteraceae), sedges (Cyperaceae), carnations (Caryophyllaceae), ferns (Polypodiaceae), bulrush (Typhaceae) and nettles (Urticaceae). Moulds were low.

Pretoria

This site has reopened after the festive break and new data should be available next week. December results: Moderate to high grass counts, moderate tree counts, and low weed counts were recorded. Trees included birch (Betulaceae), Australian pine (Casuarina sp.), cypress (Cupressaceae), ash (Fraxinus sp.), Cape holly (Ilex sp.), mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), oak (Quercus sp.) and karee (Rhus/Searsia sp.). The weeds observed were the daisy family (Asteraceae), the carnation family (Caryophyllaceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), and ferns (Polypodiaceae). Fungal spores were not significant

Bloemfontein

Pollen counts in all categories were low. Trees included mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae), poplar (Populus sp.), karee (Rhus/Searsia sp.) and elm (Ulmaceae). Weeds included the daisy family (Asteraceae), sedges (Cyperaceae), pigmyweeds (Crassulaceae), erica (Ericaceae), ferns (Pteridaceae) and plantain (Plantaginaceae). Fungal spores were low.

Kimberley

Courier delays meant no new data were available for this site but new data should be available next week. December results: Pollen levels were low. Trees detected included elm (Ulmaceae), olive (Oleaceae) and gum (Myrtaceae). Weeds were goosefoot (Chenopodiaceae) and buckwheat (Polygonaceae). Moulds were low with one spike for the allergenic spore Cladosporium. Intermittent rain removed pollen and mould from the air at this site.

Durban

Grass levels were low. Tree pollen was similarly low and the types detected were the sumac family (Anacardiaceae), acacia (Acacia spp.), cypress (Cupressaceae), mulberry (Moraceae), yellowwood (Podocarpaceae), pepper tree (Schinus spp.), and olive (Oleaceae). Low weed levels included plantain (Plantaginaceae), ragweed (Ambrosia spp.), ferns (Polypodiaceae), and sedges (Cyperaceae). Moulds were high after heavy rain.

Gqeberha

Low levels of grasses, trees, weeds, and fungal spores were seen. Trees included only acacia (Acacia sp.) and waxberry (Morella sp.) The weeds recorded were pigweed (Amaranthus sp.), carnations (Caryophyllaceae), sedges (Cyperaceae), lilies (Liliaceae),  and protea (Proteaceae).

Potchefstroom

This site has reopened after the festive break and new data should be available next week. December results: Moderate grass counts with very low tree and weed counts were recorded. Tree pollen included cypress (Cupressaceae), mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae) and plane (Platanus sp.). The weeds detected were only the daisy family (Asteraceae), sedges (Cyperaceae) and plantain (Plantaginaceae). Fungal spores were very low.