Sawadaea bicornis
This is a powdery mildew that affects the leaves of maples and sycamore (Acer)
Sawadaea tulasnei is listed in Woods et al (2024) affecting the Norway Maple, Acer platanoides, and various ornamental, non-native Acer. Phyllactinia marissalii also affects Acer species
host/microscopy 
Photograph the mildew and chasmothecia on host plant, and add host species to the comments for your record. Depending on host species of Acer, microscopic examination or verification by an expert before submission to NatureSpot will be needed
Acer species - maples and sycamore
Graham Calow
Sharnford, Fosse Meadows
26 July 2020
mildew on Field Maple
det. R Lemmon
Leicestershire & Rutland Map
Enter a town or village to see local records
MAP KEY:
Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2025+ | 2020-2024 | pre-2020
UK Map
Species profile
- Common names
- Maple Mildew
- Species group:
- fungus
- Kingdom:
- Fungi
- Order:
- Helotiales
- Family:
- Erysiphaceae
- Records on NatureSpot:
- 61
- First record:
- 03/08/2014 (Thompson, Peter)
- Last record:
- 25/09/2025 (lemmon, roy)
Total records by month
% of records within its species group
10km squares with records
The latest images and records displayed below include those awaiting verification checks so we cannot guarantee that every identification is correct. Once accepted, the record displays a green tick.
In the Latest Records section, click on the header to sort A-Z, and again to sort Z-A. Use the header boxes to filter the list.