Sycamore Tarspot - Rhytisma acerinum

Alternative names
Tarspot Fungus

This fungus causes a raised shiny black spot to appear on the leaves of the host trees.

Identification difficulty

Grows on Sycamore and sometimes on other species of Maple.

When to see it

Late Summer until the leaves fall in Autumn.

Life History

The fungus overwinters on fallen leaves. Fresh spores are produced in Spring, these have a sticky coating. The spores attach themselves to the new leaves as they form. The fungus does no lasting harm to its host tree.

UK Status

Very common and widespread in Britain.

VC55 Status

Very common in Leicestershire and Rutland.

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Leicestershire & Rutland Map


Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015

UK Map