Tar spot is a very conspicuous fungal leaf spot disease of sycamore and some maples. Whilst the large leaf spots sometimes cause growers concern, they actually do very little damage to the tree although they are very unsightly and do not make a tree showable.

Main symptoms are conspicuous raised, shiny, black leaf spots caused by Fungus in summer

• Yellow blotches form on the leaves in late spring
• By mid-summer these have developed into large (up to 15mm across), slightly raised, shiny, black spots with a narrow yellow margin
• Heavily-infected leaves may fall slightly early

Remove and burn damaged leaves to prevent spread and spray with fungicide once you have removed damaged leaves