Summary
Tree pollen is significant in Cape Town and Bloemfontein and increasing in Johannesburg. Dominant trees are mulberry, poplar and plane.
Cape Town
Tree concentrations are now significant at this sampling site and include the dominant tree mulberry (Moraceae), cypress (Cupressaceae), hackberry (Celtis), olive (Oleaceae) and pine (Pinaceae). Weeds are the daisy family (Asteraceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), erica (Ericaceae), bulrush (Typhaceae) and nettles (Urticaceae). Moulds are low, but a strong peak was noted for Alternaria, an allergenic mould.
Johannesburg
Pollen concentrations are low but tree pollen is increasing at this site. Flowering trees included the dominant tree plane (Platanaceae), acacia (Acia-type), cypress (Cupressaceae), beech (Fagus)and pine (Pinaceae). Weeds are the daisy family (Asteraceae), pigmyweeds (Crassulaceae) and erica (Ericaceae). Moulds are low.
Pretoria
Pollen concentrations would be low at this site but an increase in the variety of trees would be seen. These might be mulberry (Moraceae), yellowwood (Podocarpaceae), hackberry (Celtis), birch (Betula), pine (Pinaceae), cypress (Cupressaceae), karee (Searsia), oak (Quercus), plane (Platanaceae), willow (Salicaceae) and elm (Ulmaceae). Weeds would be slangbos (Stoebe-type), spurges (Euphorbiaceae), plantain (Plantaginaceae) and hopbush (Dodonaeae). Moulds would be low. 5-year means were used. The spore trap for this site has been repaired and will be reinstalled next week.
Bloemfontein
Trees have risen to significant levels at this site and include false olive (Buddleia), hackberry (Celtis), olive (Oleaceae), ash (Fraxinus), olive (Oleaceae), plane (Platanaceae), yellowwood (Podocarpaceae) and the dominant tree poplar (Populaceae). Weeds are pigmyweeds (Crassulaceae) and sedges (Cyperaceae) and moulds are low.
Kimberley
Pollen concentrations were all low, but more variety was seen. Trees included birch (Betula), false olive (Buddleia), hackberry (Celtis), bushwillow (Combretaceae), cypress (Cupressaceae), hackberry (Celtis), pine (Pinaceae), poplar (Populaceae) and karee (Searsia). Weeds were mugwort (Artemisia) and the daisy family (Asteraceae). Last week’s report was used as this week’s pollen strip did not reach the laboratory in time for analysis.
Durban
Moulds were moderate due to a spike in Cladosporium, the allergenic mould. Trees were moderate and included cypress (Cupressaceae), poplar (Populaceae), birch (Betula), palm (Arecaceae), poplar (Populaceae), mulberry (Moraceae), pine (Pinaceae), guarri (Euclea), monkey puzzle (Araucariaceae), pecan (Carya), yellowwood (Podocarpaceae) and Australian pine (Casuarina). Weeds were bulrush (Typhaceae), katstert (Anthospermum), the daisy family (Asteraceae), pigmyweeds (Crassulaceae), plantain (Plantaginaceae) and spurges (Euphorbiaceae). Fern spores (Polypodiaceae) were seen.
Gqeberha
There is no pollen count this week due to staff absence so 5-year means were calculated. Pollen concentrations would be low and trees might include gum (Myrtaceae), Australian pine (Casuarina), the mango and cashew family (Anacardiaceae) waxberry (Morella) and mulberry (Moraceae). Weeds could be sedges (Cyperaceae), lily (Liliaceae), mugwort (Artemisia), katstert (Anthospermum, erica (Ericaceae) and the daisy family (Asteraceae). Moulds would be low.
George
Pollen concentrations would be low at this sampling site. In the past two years the only tree seen at this time of the year was cypress and the only weed was spurge (Euphorbiaceae). Moulds would be low. Plans are being made to reinstall this spore trap and it is hoped that it will be operating again in August.
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