Summary
Tree pollen is reaching high concentrations in Bloemfontein and Johannesburg. Coastal sites have higher tree loads but have just begun their flowering cycle, so the concentrations are still low or moderate. Weeds and grasses are low at all the sampling sites.
Cape Town
The tree season has started in Cape Town and cypress (Cupressaceae), plane (Platanaceae), oak (Quercus). pine (Pinaceae), yellowwood (Podocarpaceae), olive (Oleaceae), acacia (Acacia-type), sumac (Anacardiaceae), ash (Fraxinus) monkey puzzle (Auracariaceae) and mulberry (Moraceae). Weeds are sedges (Cyperaceae), mugwort (Artemisia), the daisy family (Asteraceae) and erica (Ericaceae). Moulds are low because of the low temperatures with snow on Table Mountain.
Johannesburg:
Tree pollen reached high concentrations this week. The highest concentrations were recorded for plane (Platanaceae). Morus (Moraceae), hackberry (Celtis) and cypress (Cupressaceae), followed by oak (Quercus), karee (Rhus/Searsia), beech (Fagus), ash (Fraxinus). gum (Myrtaceae)and pine (Pinaceae). Low weed, grasses and moulds were detected. Weeds were the daisy family (Asteraceae) and lily (Liliaceae).
Pretoria:
Tree pollen increases at this time of year. Trees with the highest airborne pollen concentrations are cypress (Cupressaceae), plane (Platanaceae) pine (Pinaceae) and mulberry (Moraceae), followed by birch (Betulus), karee (Rhus/Searsia) and ash (Fraxinus). Low weed concentrations would include slangbos (Stoebe-type) and the carnation family (Caryophyllaceae). Moulds are low. 4-year means are given.
Bloemfontein:
High tree counts that exceeded the significant threshold were detected. The most prevalent tree pollen was plane (Platanaceae) which was consistently high, followed by cypress (Cupressaceae), olive (Oleaceae) and elm (Ulmaceae) and lower concentrations of birch (Betulus), pecan (Carya), oak (Quercus), pine (Pinaceae), mulberry (Moraceae), karee (Rhus/Searsia) and waxberry (Morella). weeds were found in low concentrations and included mugwort (Artemisia), the daisy family (Asteraceae), sedges (Cyperaceae), ferns (Polypodiaceae) and lily) Liliaceae). Grasses and moulds were low.
Kimberley
Extremely low pollen and mould concentrations were detected at this sampling site. Trees included cypress (Cupressaceae), poplar (Populaceae) and mulberry (Moraceae). Weeds were the daisy family (Asteraceae), sorrel (Rumex) and the carnation family (Caryophyllaceae). No rain fell during this sampling week, but signs of grass burning were evident, in the numbers of burned stamens and nematodes).
Durban
Pollen and moulds are low at this time of year at this coastal site. Flowering trees at this time of year include cypress (Cupressaceae), mulberry (Moraceae), hackberry (Celtis), yellowwood (Podocarpaceae), pine (Pinaceae) and beech (Fagus)> weeds are erica (Ericaceae), reeds (Restionaceae), nettles (Urticaceae) and mugwort (Artemisia). Moulds fluctuate from low to moderate. 4-year means are given.
Gqeberha:
Pollen and mould concentrations were all low at this site. No tree pollen was detected and weeds included aloe (Asphodelaceae) and the daisy family (Asteraceae).
Potchefstroom
This site is not operating.
George
Low concentrations of tree, grass and weed pollen were detected at this sampling site. Trees included cypress (Cupressaceae), bushwillow (Combretaceae), poplar (Populaceae), yellowwood (Podocarpaceae) and pine (Pinaceae). Weeds were sedges (Cyperaceae), mezereum (Thymelaeaceae), protea (Proteaceae), nettle (Urticaceae) and mugwort (Artemisia). Moulds were insignificant.
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
