Summary
Grass pollen is high in Pretoria and Potchefstroom. Elevated weed counts were detected in Potchestroom and mould spores were moderate in Durban, Kimberley and Potchefstroom.
Cape Town
Heavy rain in Cape Town reduced the pollen and fungal spore catch. Grass was low. Low tree concentrations included birch (Betulaceae), gum (Myrtaceae) and cypress (Cupressaceae). Scanty weed pollen included sorrel (Rumex spp.), plantain (Plantaginaceae) and protea (Proteaceae), Mould spores were low.
Calvinia
The spore trap is not operating at present so findings for the same time period in 2022 are repeated. All pollen categories as well as fungal spore counts were low during this sampling period. Tree pollen included only the sumac family (Anacardiaceae) and waxberry (Morella sp.), while the daisy family (Asteraceae), goosefoot (Chenopodiaceae) and nettles (Urticaceae) were detected in the weeds category.
Johannesburg
Grasses were low. Trees detected included Australian pine (Casuarina spp.), pine (Pinaceae), gum (Myrtaceae) and karee (Rhus/Searsia spp.). Weeds included pigweed (Amaranthaceae), lily (Liliaceae), slangbos (Stoebe-type) and the carnation family (Caryophyllacea). Mould spores were extremely low.
Pretoria
Grasses were moderate with high counts on some days. Tree pollen was low and the types detected were birch (Betulaceae), cypress (Cupressaceae), mulberry (Moraceae), gum (Myrtaceae), mesquite (Prosopis) and karee (Rhus/Searsia). Weeds were mugwort (Artemisia), daisy (Asteraceae), goosefoot (Chenopodiaceae), sedge (Cyperaceae) and erica (Ericaceae). Mould spores were low,
Bloemfontein
The sample was not delivered to the laboratory in time for processing so last week’s findings are repeated. Grasses were moderate. Low tree pollen concentrations included poplar (Populaceae) and elm (Ulmaceae). Weeds were similarly low and only sedge (Cyperaceae) and goosefoot (Chenopodiaceae) were detected. Mould spores were extremely low.
Kimberley
The Kimberley pollen sample was not delivered in time for processing so the means of previous years’ findings (2019-2022) are shown. Trees flowering at this time are waxberry (Morella spp.), olive (Oleaceae) and karee (Rhus/Searsia spp.). Weeds previously detected were the daisy family (Asteraceae), goosefoot (Chenopodiaceae) and nettles (Urticaceae). Mould spores were moderate.
Durban
Low grass, tree and weed concentrations were observed at this site. Trees included birch (Betulaceae), cypress (Cupressaceae) and gum (Myrtaceae). Weeds were ferns (Polypodiaceae), borage (Boraginaceae), plantain (Plantaginaceae), moss (Bryophites), sedges (Cyperaceae), ragweed (Ambrosia spp.), protea (Proteaceae), nettles (Urticaceae), the daisy family (Asteraceae) and sundew (Droseraceae). Mould spores were moderate with spikes for ascospores following rain.
Gqeberha
Pollen concentrations were low at this site. Trees included Australian pine (Casuarina spp.), waxberry (Morella spp.) and karee (Rhus/Searsia spp.). Weeds were pigweed (Amaranthaceae), goosefoot (Chenopodiaceae), sedge (Cyperaceae), erica (Ericaceae) and slangbos (Stoebe-type). Moulds were extremely low.
Potchefstroom
Grasses were high on days without rain. Tree concentrations were lower than the previous week, reduced by rain. The types detected were palm (Arecaceae), cypress (Cupressaceae), ash (Fraxinus spp.), gum (Myrtaceae), mulberry (Moraceae), pine (Pinaceae), oak (Quercus spp.) and elm (Ulmaceae). Moderate weed concentrations included pigweed (Amaranthaceae), ragweed (Ambrosia spp.), mugwort (Artemisia spp.), the daisy family (Asteraceae), plantain (Plantaginaceae), sedge (Cyperaceae), and nettle (Urticaceae). Moulds were low but strong, significant spikes for Cladosporium were present on rain free days.
