Summary
The significant grass concentrations at summer rainfall, inland sites continued this week. No peaks were seen for trees, but a short sharp increase in sedge grass was seen at Vanderbijlpark, south of Johannesburg. Grasses and sedges were also high in central Johannesburg. Durban was the only site with significant mould concentrations.
Cape Town
Tree, grass and weed pollen was low at this site. Trees would include gum (Myrtaceae), which is insect pollinated but flowering all over Cape Town at present, waxberry (Morella) and cypress (Cupressaceae). Weeds are likely to be the daisy family (Asteraceae), English plantain (Plantaginaceae), the dominant weed at all the listed sites this week and erica (Ericaceae), a fynbos plant. Moulds are low in the absence of rain. 5-year means are shown.
Johannesburg
Grasses were high. Low tree concentrations included birch (Betulus), false olive (Buddleia) bushwillow (Combretaceae), mulberry (Moraceae), olive (Oleaceae) and elm (Ulmaceae). Weeds were pigweed (Amaranthaceae), mugwort (Artemisia), the daisy family (Asteraceae), lily (Liliaceae), plantain (Plantaginaceae), ferns (Polypodiaceae) and bulrush (Typhaceae). The dominant weed at this site was sedge ((Cyperaceae) and it reached high concentrations. Moulds were low.
Johannesburg South
The strong grass peak continued at this site. Low tree concentrations included birch (Betulus), ash (Fraxinus), karee (Rhus/Searsia) and elm (Ulmaceae). Weeds were the daisy family (Asteraceae), the carnation family (Caryophyllaceae), bulrush (Typhaceae) and nettles (Urticaceae) in low concentrations. A peak was seen for sedges (Cyperaceae). Moulds were low,
Pretoria
Grasses are usually moderate at this tome of year at this site. Low tree concentrations would include linden (Tiliaceae), waxberry (Morella), karee (Rhus/Searsia), palm (Arecaceae) and birch (Betulaceae). Weeds are likely to be the daisy family (Asteraceae), plantain (Plantaginaceae) and protea (Proteaceae) while moulds are low.
Bloemfontein
At this time of year grasses are moderate, while tree and weed pollen is low. Tres would be false olive) Buddleia), cypress (Cupressaceae) and olive (Oleaceae) and weeds are likely to be the daisy family (Asteraceae) and goosefoot (Chenopodiaceae), while moulds are low. 5-year means are shown.
Kimberley
Grasses are generally high at this time of year. Low trees typically include waxberry (Morella), pine (Pinaceae), hackberry (Celtis), gum (Myrtaceae) and olive (Oleaceae). Weeds would be sedges (Cyperaceae), the daisy family (Asteraceae), nettles (Urticaceae) and goosefoot (Chenopodiaceae). Moulds are typically low. The strip did not reach the laboratory in time, but real counts will be added once the analysis is completed.
Durban
Pollen in the categories of trees, grasses and weeds was very low. Trees included birch (Betulus), karee (Rhus/Searsia) and elm (Ulmaceae). Weeds were ragweed (Ambrosia), the daisy family (Asteraceae), sedges (Cyperaceae), ferns (Polypodiaceae), knotweed (Persicaria), plantain (Plantaginaceae) and nettles (Urticaceae). Moulds were moderate.
Gqeberha
All pollen concentrations were low. The only tree pollen detected was olive (Oleaceae) and weeds were pigweed (Amaranthaceae) and the daisy family (Asteraceae), while moulds were low.
George
Tree, grass and weed pollen counts are typically low at this time of year. Trees may include the beautiful monkey puzzle (Auracariaceae) and Australian pine (Casuarina). Weeds are typically the daisy family (Asteraceae), sedges (Cyperaceae), erica (Ericaceae) and ferns. Moulds/fungal spores increase after rain when strong spikes may be seen for ascospores and smaller spikes often occur for the allergenic mould Cladosporium. These findings are repeated for the same period in 2024.
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