Summary
Torrential rain occurred at many of these sites. In cities where rain was prolonged (Johannesburg) pollen and mould was washed from the air so low counts were seen. In warmer areas (Durban and Kimberley), despite heavy rain, moulds increased sharply. Average grass counts were low but some moderate grass count days were seen in Pretoria and Johannesburg.
Cape Town
The grass, trees and weed pollen loads were slight during this hot, dry sampling period. Trees included elm (Ulmaceae), olive (Oleaceae, birch (Betulaceae), poplar (Populaceae), peppertree (Schinus spp.) and gum (Myrtaceae). Weeds were goosefoot (Chenopodiaceae), the mallow family (Malvaceae), erica (Ericaceae), sedges (Cyperaceae) and the daisy family (Asteraceae). Moulds were very low.
Calvinia
The sampler at this site is now operational and findings will be available from next week. Archived and recent data averages are shown. Moulds are likely to be low together with tree, grass and weed pollen. Flowering weeds detected in autumn are the daisy family (Asteraceae) and goosefoot (Chenopodiaceae). Trees would be karee (Rhus) and gum (Myrtaceae).
Johannesburg
Torrential, continuous rain at this site caused widespread flooding. Pollen and moulds were washed from the air. Low tree pollen included birch (Betulaceae), Australian pine (Casuarina spp.) and yellowwood (Podocarpaceae). Weeds were pigweed (Amaranthaceae), the carnation family (Caryophyllaceae), spurges (Euphorbiaceae), the daisy family (Asteraceae) and slangbos (Stoebe-type). Moulds were low.
Pretoria
Heavy rainfall at this site has resulted in changes to the pollen catch. The average daily grass score was low but moderate levels were seen towards the end of the week. Low tree loads included hackberry (Celtis spp.), cypress (Cupressaceae), and mulberry (Moraceae). Moulds increased sharply to moderate levels with small peaks for basidiospores and Cladosporium and a spike for ascospores.
Bloemfontein
This pollen strip did not reach the laboratory in time so last week’s results are repeated. Grasses were low. Low tree pollen included acacia (Acacia spp.), false olive (Buddleja), olive (Oleaceae), elm (Ulmaceae) poplar (Populaceae), mulberry (Moraceae) and karee (Rhus/Searsia spp.). Low weeds were mugwort (Artemisia spp), plantain (Plantaginaceae), the daisy family (Asteraceae) and erica (Ericaceae). Mould spores were low.
Kimberley
Low pollen loads were detected. Tree pollen included elm (Ulmaceae) and gum (Myrtaceae). Weeds were nettles (Urticaceae), ragweed (Ambrosia spp.) and plantain (Plantaginaceae). Moulds were moderate with strong spikes for ascospores, Cladosporium and basidiospores (includes mushroom spores) at the end of the sampling week.
Durban
Tree, grass and weed pollen loads were low. Trees included mulberry (Moraceae), gum (Myrtaceae), olive (Oleaceae), waxberry (Morella spp.) and the sumac family (Anacardiaceae). Weeds were ragweed (Ambrosia spp.), goosefoot (Chenopodiaceae), ferns (Polypodiaceae), plantain (Plantaginaceae)and knotweed (Persicaria spp.). Moulds were high with strong spikes for ascospores and basidiospores (includes mushroom spores).
Gqeberha
There were light loads of pollen and mould in the ambient air. Grass pollen levels were low, no tree pollen at all was detected and weeds included pigweed (Amaranthaceae), the carnation family(Caryophyllaceae), slangbos (Stoebe-type), sedge (Cyperaceae) and lily (Liliaceae). Moulds were low.
Potchefstroom
The newly reinstated spore trap ran for insufficient days to show accurate results but from next week results should be posted.
