Summary
During this midwinter period with low temperatures, heavy, rain, floods and snow, extremely low pollen and mould concentrations were recorded.
Cape Town
The spore trap could not be changed due to flooding. Last week’s findings are repeated. From a waterlogged Cape Town, low concentrations of pollen and moulds have been recovered. Trees detected were elm (Ulmaceae) and karee (Searsia/Rhus). No weeds were observed and grasses and moulds were exceptionally low. Small peaks were seen for the rain spore, Pleospora.
Johannesburg
Moulds and pollen were detected in minute concentrations during this sampling period. Trees were Australian (Casuarina), cypress (Cupressaceae), beech (Fagus sylvatica), gum (Myrtaceae), plane (Platanaceae). Poplar (Populaceae) and karee (Rhus/Searsia). Weeds were the daisy family (Asteraceae) and slangbos (Stoebe-type).
Pretoria
4-year means for this site are shown. Concentrations of pollen and fungal spores were very low. Trees detected were palm (Arecaceae), gum (Myrtaceae) and karee (Searsia/Rhus) and weeds were knotweed (Persicaria) and goosefoot (Chenopodiaceae).
Bloemfontein
The pollen and mould concentrations remain low during this cold midwinter period. Trees included sumac (Anacardiaceae), cypress (Cupressaceae), mulberry (Moraceae), olive (Oleaceae) and karee (Rhus/Searsia). Weeds were goosefoot (Chenopodiaceae), sedges (Cyperaceae), heath (Ericaceae) and sorrel (Rumex). Grasses were scanty.
Kimberley
Last week’s findings are repeated as the pollen strip did not reach the laboratory in time for analysis. The pollen strip contained large amounts of debris, including signs of grass burning, nematodes and phytoliths. Frost occurred during the sampling period. Trees detected were bushwillow (Combretaceae), palm (Arecaceae) and karee (Searsia/Rhus). Weeds were heath (Ericaceae), goosefoot (Chenopodiaceae) and spurges (Euphorbiaceae). Moulds were low.
Durban:
All pollen and mould concentrations were extremely low. Trees included cypress (Cupressaceae) and beech (Fagus sylvatica). Weeds were nettles (Urticaceae), knotweed (Persicaria), goosefoot (Chenopodiaceae), ferns (Polypodiaceae) and the daisy family (Asteraceae). Grasses were rarely detected.
Gqeberha
No pollen at all was detected at this sampling site and mould concentrations were extremely low.
Potchefstroom
This spore trap is not operating.
George
The pollen and mould concentrations were barely discernible during a week of heavy rain which removed all airborne aeroallergens from the air. Trees included bushwillow (Combretaceae), cypress (Cupressaceae) and pine (Pinaceae). Weeds were spurges (Euphorbiaceae) and erica (Ericaceae).
Reference Range
Grass: Low: 0-5 Moderate: 6-20 High: 21-200
Trees: Low: 0-15 Moderate: 16-90 High: 91-1500
Weeds: Low: 0-10 Moderate: 10-50 High: 51-500
Moulds: Low: 0-900 Moderate: 900-2500 High 2500-25000
Unit: per cubic metre
