Weekly Report

9 September 2022

City
Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Summary

Very high tree pollen levels were seen across most of South Africa. Bloemfontein, Pretoria and Johannesburg delivered the highest counts, followed by Cape Town and Kimberley. Grass and weed counts remained low in most cities, except Cape Town and Durban where moderate counts were detected. No new data were available for Calvinia, but likely the weed counts at this site remained high. Fungal spore counts were low across the country, except in Durban where moderate levels were seen.

Cape Town

Very high tree counts, moderate weed counts and low grass counts were detected during this sampling period. Trees were dominated by cypress (Cupressaceae) pollen, with lower levels of acacia (Acacia sp.), birch (Betulaceae), Australian pine (Casuarina sp.), cedar (Cedrus sp.), ash (Fraxinus sp.), mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), plane (Platanus sp.), yellowwood (Podocarpaceae) and oak (Quercus sp.) present. Weeds included elevated levels of nettle pollen (Urticaceae) and lower counts of mugwort (Artemisia sp.), the daisy family (Asteraceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), erica (Ericaceae), the cabbage family (Brassicaceae), proteas (Proteaceae) and plantain (Plantaginaceae). Fungal spore counts were low.

Calvinia

A technical issue at this site meant no new data were available for this week. The findings from the last sampling period are repeated. Very high weed pollen counts were likely seen due to elevated mugwort (Artemisia sp.) levels. Other weed pollen included the daisy family (Asteraceae), the cabbage family (Brassicaceae), goosefoot (Chenopodiaceae) and nettles (Urticaceae). Moderate tree counts included elevated hackberry (Celtis sp.) and mesquite (Prosopis sp.), as well as pollen from the sumac family (Anacardiaceae), cypress (Cupressaceae), olive (Oleaceae) and pine (Pinaceae). Moulds were very low.

Johannesburg

Very high tree levels with low grass and weed counts were detected. Hackberry (Celtis sp.), mulberry (Moraceae) and plane (Platanus sp.) had the highest counts, with lower levels of birch (Betulaceae), Australian pine (Pinaceae), cypress (Cupressaceae), the pea family (Fabaceae), ash (Fraxinus sp.), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), yellowwood (Podocarpaceae), poplar (Populus sp.), oak (Quercus sp.), willow (Salix sp.) and elm (Ulmaceae) also present. Weeds included only pigweed (Amaranthus sp.) and sedges (Cyperaceae). Fungal spores were very low.

Pretoria

Very high tree counts with low grass and weed counts were recorded. The dominant trees were mulberry (Moraceae), birch (Betulaceae) and plane (Platanus sp.). Lower levels of bushwillow (Combretaceae), hackberry (Celtis sp.), cypress (Cupressaceae), ash (Fraxinus sp.), gum (Myrtaceae), pine (Pinaceae), poplar (Populus sp.), oak (Quercus sp.) and karee (Rhus/Searsia sp.) were also seen. Weeds included the daisy family (Asteraceae), the carnation family (Caryophyllaceae) and goosefoot (Chenopodiaceae) Fungal spore counts were low.

Bloemfontein

Very high tree counts with low grass and weed counts were seen. Tree pollen included significant levels of hackberry (Celtis sp.) as well as elevated levels of cypress (Cupressaceae), mulberry (Moraceae), waxberry (Myricaceae), plane (Platanus sp.) and poplar (Populus sp.). Lower counts for acacia (Acacia sp.), bushwillow (Combretaceae), olive (Oleaceae), pine (Pinaceae) and karee (Rhus/Searsia sp.) were also seen. The weed pollen detected were mugwort (Artemisia sp.), the daisy family (Asteraceae) and goosefoot (Chenopodiaceae). Mould counts were low.

Kimberley

Very high tree counts with low grass, weed and fungal spore counts were seen. Tree pollen included elevated levels of birch (Betulaceae), cypress (Cupressaceae), plane (Platanus sp.) and mulberry (Moraceae). Lower counts of acacia (Acacia sp.), hackberry (Celts sp.), bushwillow (Combretaceae), ash (Fraxinus sp.), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), poplar (Populus sp.) and oak (Quercus sp.) were also present. The weeds detected included the daisy family (Asteraceae), carnations (Caryophyllaceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), erica (Ericaceae), spurges (Euphorbiaceae), iris (Iridaceae), plantain (Plantaginaceae) and fern spores (Polypodiaceae).

Durban

Moderate fungal spore levels as well as moderate tree pollen levels were seen. The tree pollen detected include acacia (Acacia sp.), maple (Acer sp.), the sumac family (Anacardiaceae), palm (Arecaceae), birch (Betulaceae), cypress (Cupressaceae), hackberry (Celtis sp.), Australian pine (Casuarina sp.), the ebony family (Ebenaceae), beech (Fagus sp.), ash (Fraxinus sp.), mulberry (Moraceae), pine (Pinaceae), gum (Myrtaceae), yellowwood (Podocarpaceae), plane (Platanus sp.) and lindens (Tiliaceae). Grass counts were low and weed counts were moderate, with ice plants (Aizoaceae), mugwort (Artemisia sp.), goosefoot (Chenopodiaceae), sedges (Cyperaceae), plantain (Plantaginaceae), sorrel (Rumex sp.) and nettles (Urticaceae).

Gqeberha

Very low grass, tree and fungal spore counts were seen. Tree pollen included acacia (Acacia sp.), cedar (Cedrus sp.), waxberry (Myricaceae), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae) and yellowwood (Podocarpaceae). Weed counts were low and included katstert (Anthospermum sp.), mugwort (Artemisia sp.), the daisy family (Asteraceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), erica (Ericaceae), spurges (Euphorbiaceae) lilies (Liliaceae), restios (Restionaceae) and mezereum (Thymelaeaceae).