Weekly Report

25 August 2023

City
Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Tree pollen is high at many sites and plane tree is now the dominant pollen.

The Cape grass season has started early (27 August) after heavy winter rainfall in this area so be prepared for symptoms of hay fever, rhinitis and eye allergy.

Trees pollen is increasing rapidly in Gauteng and Bloemfontein and plane tree is now the dominant pollen.

Cape Town

On sunny days tree pollen was moderate and included cypress (Cupressaceae), which is still the dominant aeroallergen. plane (Platanaceae), appeared for the first time this week, albeit at low concentrations and other types included oak (Quercus spp.), pine (Pinaceae), walnut (Juglandaceae), monkey puzzle (Araucaria angustifolia), elm (Ulmaceae), gum (Myrtaceae), birch (Betulaceae), and peppertree (Schinus spp.). Weeds were scarce and included sedge (Cyperaceae), goosefoot (Chenopodiaceae) and nettle (Urticaceae). Grasses and mould spore concentrations were low.

Calvinia

This site is not operational.

Johannesburg

Tree concentrations increased sharply at this site. Plane (Platanaceae) was the dominant pollen but high counts were seen for cypress (Cupressaceae), mulberry (Moraceae) and ash (Fraxinus spp.). Other flowering trees were pecan (Carya spp.), palm (Arecaceae), oak (Quercus spp.), karee (Rhus/Searsia spp), willow (Salicacea) and elm (Ulmaceae). Grasses were low and the only weeds were pigweed (Amaranthaceae) and lily (Liliaceae). Mould spores were low.

Pretoria

Tree pollen increased at this site during the past week. The dominant trees were birch (Betulaceae), plane (Platanaceae) and mulberry (Moraceae). Other tree pollen included cypress (Cupressaceae), Australian pine (Casuarina spp.), pine (Pinaceae), hackberry (Celtis spp.), ash (Fraxinus spp) and oak (Quercus spp.). Grasses were low. Low weed concentrations included the daisy family (Asteraceae), erica (Ericaceae) and plantain (Plantaginaceae). Mould spores were low.

Bloemfontein

Tree pollen surged during the past week. Olive (Oleaceae) was the dominant pollen followed by poplar (Populaceae), plane (Platanaceae), cypress (Cupressaceae), pine (Pinaceae) and elm (Ulmaceae). Small concentrations of other trees included karee (Rhus/Searsia spp.), ash (Fraxinus spp.), mulberry (Moraceae) and yellowwood (Podocarpaceae). Weeds were low but a small spike was seen for sedge (Cyperaceae). Grasses, and mould spores were low.

Kimberley

Very low pollen and mould spore results were detected at this sampling site in all categories. Trees included hackberry (Celtis spp.), mulberry (Moraceae), cypress (Cupressaceae), pine (Pinaceae) and the sumac family (Anacardiaceae). Weeds were goosefoot (Chenopodiaceae) and nettles (Urticaceae). Mould spores were low.

Durban

Low pollen concentrations were detected during this sampling cycle. Trees were yellowwood (Podocarpus). Birch (Betulaceae), mulberry (Moraceae), cypress (Cupressaceae), olive Oleaceae), pine (Pinaceae) and beech (Fagus spp.). Weeds were sorrel (Rumex spp.), nettles (Urticaceae) and goosefoot (Chenopodiaceae). Grasses and mould spores were low.

Gqeberha

This spore trap is not operational during service, but findings should be available soon.

Potchefstroom: Tree concentrations were moderate with high counts for plane (Platanaceae) and cypress (Cupressaceae). Other flowering trees were pine (Pinaceae), gum (Myrtaceae), guarri (Euclea spp.) and karee (Rhus/Searsia). Grasses and weeds were low, and the only weeds detected were nettle (Urticaceae) and slangbos (Stoebe-type).