Erysiphe polygoni
Erysiphe polygoni is a powdery mildew affecting Knotgrass and otehr species in the Polygonaceae family.
host 
Photograph on host plant, and add host species to the comments for your record.
Frequently on Knotgrass (Polygonum aviculare or P arenastrum); also on Docks (Rumex), Persicaria and Knotweed (Fallopia) species
Geoffrey Hall
Leicester, London Road
08 September 2019
Leaves with chasmothecia
Graham Calow
Sapcote, Grace Road
06 September 2020
mildew on Knotgrass
Geoffrey Hall
Leicester, London Road
08 September 2019
Chasmothecia and asci
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Species profile
- Species group:
- fungus
- Kingdom:
- Fungi
- Order:
- Helotiales
- Family:
- Erysiphaceae
- Records on NatureSpot:
- 13
- First record:
- 14/09/2017 (lemmon, roy)
- Last record:
- 24/08/2025 (lemmon, roy)
Total records by month
% of records within its species group
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Latest images
Latest records
Geoffrey Hall
Leicester, London Road
08 September 2019
Habit shot
Graham Calow
Sapcote, Cook's Lane
12 July 2020
Graham Calow
Sapcote, Cook's Lane
12 July 2020
