Summary
The dominant tree at all the sites with high tree counts was plane, except for Johannesburg where oak tree pollen had the highest counts. Grasses are now moderate in Pretoria, but low at all the other sites.
Cape Town
Pollen concentrations were reduced by heavy rainfalls, but tree counts remained high. The dominant tree was plane, followed by cypress (Cupressaceae), birch (Betulaceae), Cape holly (Ilex), jacaranda (Bignoniaceae) mulberry (Moraceae), waxberry (Morella), olive (Oleaceae), gum (Myrtaceae), pine (Pinaceae) and oak (Quercus). Weeds were low and included the daisy family (Asteraceae) erica (Ericaceae), protea (Proteaceae) and nettle (Urticaceae). Moulds were low.
Johannesburg Central
Tree pollen was high and included oak (Quercus), now the dominant tree pollen, acacia (Acacia-type), hackberry (Celtis), false olive (Buddleia), bushwillow (Combretaceae), cypress (Cupressaceae), flamboyant (Delonix), ebony (Ebenaceae), beech (Fagus), privet (Ligustrum), sweetgum (Liquidamber), gum (Myrtaceae), mulberry (Moraceae), waxberry (Morella), olive (Oleaceae), pine (Pinaceae), plane (Platanaceae), yellowwood (Podoacarpaceae), karee (Searsia) and elm (Ulmaceae). Low weeds included pigweed (Amaranthaceae), lily (Liliaceae), the daisy family (Asteraceae), pigmyweeds (Crassulaceae), spurges (Euphorbiaceae), nettles (Urticaceae), slangbos (Stoebe-type), protea (Proteaceae) and ferns (Polypodiaceae). Moulds were low.
Johannesburg South
No data is available for this site. Pollen monitoring has stopped.
Pretoria
Pollen concentrations decreased at this site. Trees were hackberry (Celtis), cypress (Cupressaceae), persimmon (Ebenaceae), the pea family (Fabaceae), mulberry (Moraceae), olive (Oleaceae), plane (Platanaceae), yellowwood (Podocarpaceae), poplar (Populaceae), karee (Searsia), and elm (Ulmaceae). Weeds were lily (Liliaceae), plantain (Plantaginaceae), fern (Polypodiaceae) and nettle (Urticaceae). Grass was moderate and moulds were low.
Bloemfontein
Tree pollen is high and the dominant taxon is plane (Platanaceae), followed by false olive (Buddleia) and hackberry (Celtis). Other flowering trees include birch (Betulaceae), bushwillow (Combretaceae), cypress (Cupressaceae), ash (Fraxinus), waxberry (Morella), gum (Eucalyptus), pine (Pinaceae), yellowwood (Podocarpaceae), poplar (Populaceae), oak (Quercus), karee (Searsia) and elm (Ulmaceae). Grasses were extremely low. Weeds were moderate and included the daisy family (Asteraceae), sedges (Cyperaceae), pigmyweeds (Crassulaceae), lily (Liliaceae), plantain (Plantaginaceae) and ferns (Polypodiaceae). Moulds were low.
Kimberley
Pollen decreased at this site. Low tree concentrations included sumac (Anacardiaceae), false olive (Buddleia), hackberry (Celtis), cypress (Cupressaceae), olive (Oleaceae), mulberry (Moraceae), yellowwood (Podocarpaceae) and karee (Searsia). Weeds were goosefoot (Chenopodiaceae), pigmyweeds (Crassulaceae), erica (Ericaceae), mallows (Malvaceae) and rose (Rosaceae). Moulds were extremely low.
Durban
Tree concentrations were significant at this site and included maple (Acer), monkey puzzle (Araucaria), pecan (Carya), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), plane (Platanaceae). yellowwood (Podocarpaceae), oak (Quercus) and karee (Searsia). Weeds were low and were sedges (Cyperaceae), erica (Ericaceae), spurges (Euphorbiaceae), nightshade (Solanaceae) and nettle (Urticaceae). Moulds were moderate with significant spikes for the allergenic mould, Cladosporium. Tree pollen was significant at this site.
Gqeberha
Tree pollen was low to moderate and included the monkey puzzle tree (Araucaria), Australian pine (Casuarina), cedar (Cedrus), cypress (Cupressaceae), olive (Oleaceae), pine (Pinaceae) and yellowwood (Podocarpaceae). Weeds were the daisy family (Asteraceae), pigweed (Amaranthaceae), katstert (Anthospermum), coffee bush (Bruniaceae), sedges (Cyperaceae) and erica (Ericaceae). Moulds were low.
George
Pollen concentrations were low at this site. Trees detected were acacia (Acia-type), coral tree (Erythrina), waxberry (Morella) and pine (Pinaceae). Weeds were the daisy family (Asteraceae) and moulds were low.
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