Weekly Report

17 January 2020

Overall Risk
Tree Pollen
Grass Pollen
Weed Pollen
Mould Spores

Cape Town

Low fungal spores, grasses, trees and weeds were seen during this hot, dry sampling week. The tree pollen was mostly eucalyptus which is insect pollinated but these trees are flowering strongly in the Cape at present and very low numbers of white stinkwood. Weed pollen detected was daisy and English Plantain.


Grass counts decreased from those of the previous week, but occasional moderate counts were recorded. Tree levels were low and included: birch, olive, oak, mulberry, eucalyptus and plane. Low weed levels included: goosefoot, daisy and English Plantain. Mould levels were uniformly low.


Grass levels increased sharply to moderate levels. Tree pollen was low and included acacia, buddleja, cypress, eucalyptus, oak and olive. Weed pollen was similarly low and consisted of daisy and English Plantain. Mould levels were consistently low.


Fungal spores increased to high levels again this week. Grasses also increased, exceeding 10 grains/cu M on the last day of the sampling week, although the average count was low. Tree pollen numbers were low and only mulberry pollen was detected. Ambrosia spp (ragweed) appeared in the air for the first time. The pollen has not yet been identified to species levels, but it is a very important finding as ragweed pollen has not previously been found in pollen counts from South Africa. Fern, dasiy and Rumex pollen was also detected.


Grass counts have increased and the levels were moderate to high throughout the sampling week. Tree pollen levels were low and sparse numbers of jacaranda, Erythrina (coral tree), olive and Casuarina pollen were detected. Weed counts were very low and consisted of erica, English Plantain and Stoebe, a large family of indigenous shrubs.


Mould counts were low, but small spikes were seen for Cladosporium and ascospores. The tree levels were low and pollen detected included acacia, palm, olive, Rutaceae (the citrus family) and Casuarina. Weed pollen was also low and consisted of: Protea and erica.


Grass counts increased sharply at the end of this sampling week and although the mean score was low, a significant level was reached on the last day of the measured week. Low levels were detected for trees (acacia, white stinkwood, olive and casuarina) and weeds (goosefoot and daisy). The mean mould count was low, but significant scores were seen for Alternaria, an allergenic fungal spore, or mould.