Summary
Tree counts were high to very high in Cape Town, Johannesburg and Pretoria. Moderate tree counts were detected in Calvinia (elevated mesquite counts) and also in Bloemfontein. Weed and grass pollen was generally low, except for moderate grasses detected in Cape Town and moderate weed levels in Gqeberha. Fungal spores were low across South Africa.
Cape Town
Grasses increased to moderate levels. Trees decreased on average but significant counts were seen for olive (Oleaceae) and oak (Quercus sp). Other tree pollen detected included cypress (Cupressaceae), pine (Pinaceae), gum (Myrtaceae), hackberry (Celtis sp.), beech (Fagus sp.), plane (Platanaceae), mulberry (Moraceae) and birch (Betulaceae). Weed pollen included sedges (Cyperaceae), mugwort (Artemisia sp.), nettles (Urticaceae), plantain (Plantaginaceae) and buckwheat (Polygonaceae). Moulds were very low but small spikes were seen for Alternaria, an allergenic mould/fungal spore.
Calvinia
Grass pollen levels were moderate. Tree pollen was also moderate with significant spikes for mesquite (Prosopis sp.). Other trees identified were the sumac family (Anacardiaceae), bushwillow (Combretaceae), cypress (Cupressaceae), pecan (Carya sp.), pine (Pinaceae) and olive (Oleaceae). Weeds detected included the daisy family (Asteraceae), goosefoot (Chenopodiaceae), mugwort (Artemisia sp.) and nettles (Urticaceae). Moulds were extremely low.
Johannesburg
Tree counts were high, but weed, grass and mould counts were very low. The tree pollen detected was acacia (Acacia sp.), birch (Betulaceae), hackberry (Celtis sp.), bushwillow (Combretaceae), cypress (Cupressaceae), ash (Fraxinus sp.), mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae), pine (Pinaceae), plane (Platanus sp.), yellowwood (Podocarpaceae), poplar (Populaceae), oak (Quercus sp.), willow (Salix sp.) and elm (Ulmaceae). Weeds included only pigweed (Amaranthus sp.), mugwort (Artemisia sp.) and sedges (Cyperaceae).
Pretoria
Very high tree levels with low grass, weed and fungal spore counts were seen during this sampling period. The dominant trees were bushwillow (Combretaceae), ash (Fraxinus sp.), olive (Oleaceae) and plane (Platanus sp.), while lower levels of acacia (Acacia sp.), birch (Betulaceae), Australian pine (Casuarina sp.), hackberry (Celtis sp.), lemon/orange pollen (Citrus sp.), cypress (Cupressaceae), mulberry (Moraceae), gum (Myrtaceae), pine (Pinaceae), poplar (Populaceae) and oak (Quercus sp.) were observed. Weeds included the daisy family (Asteraceae), goosefoot (Chenopodiaceae), sedges (Cyperaceae), erica (Ericaceae), spurges (Euphorbiaceae) and rushes (Juncus sp.).
Bloemfontein
Tree, grass and weed pollen levels were not significant. Trees included acacia (Acacia sp.), bushwillow (Combretaceae), cypress (Cupressaceae), the sumac family (Anacardiaceae), false olive (Buddleja sp.), olive (Oleaceae), plane (Platanaceae), pine (Pinaceae), mesquite (Prosopis sp.), yellowwood (Podocarpaceae), gum (Myrtaceae), elm (Ulmaceae), oak (Quercus sp.) and mulberry (Moraceae). Weeds detected were goosefoot (Chenopodiaceae), nettles (Urticaceae) and the daisy family (Asteraceae). Moulds were low.
Kimberley
Tree, grass and weed pollen levels were low. Trees included the monkey puzzle tree (Araucaria sp.), olive (Oleaceae), elm (Ulmaceae), gum (Myrtaceae), yellowwood (Podocarpaceae) pecan (Carya sp.)and bushwillow (Combretaceae). Weeds detected were goosefoot (Chenopodiaceae), protea (Proteaceae), sedges (Cyperaceae) and nettles (Urticaceae). Moulds were low.
Durban
The adhesive on the cellulose strip used to collect the pollen was extremely patchy, so these findings are likely artificially low. Grass, tree and weed pollen was very low, as were moulds. Trees detected included pecan (Carya sp.) and pine (Pinaceae). Weeds were goosefoot and knotweed (Persicaria sp.). Moulds were low but small spikes for Cladosporium, an allergenic fungal spore, were seen.
Gqeberha
Weed pollen counts were moderate, but tree, grass and mould levels remained low. Weeds included elevated mezereum (Thymelaeaceae) counts, with lower levels of pigweed (Amaranthus sp.), katstert (Anthospermum sp.), mugwort (Artemisia sp.), the daisy family (Asteraceae), ericas (Ericaceae), spurges (Euphorbiaceae) and vygies (Ruschia sp.) seen. The tree pollen detected was only acacia (Acacia sp.), pine (Pinaceae) and karee (Rhus/Searsia sp.).
