Fireblight is a bacterial disease that kills the shoots of apples, pears giving the plant the appearance of having been scorched by fire.
Fireblight infects members of the Rosaceae family including apples and pears; also includes Cotoneaster, Sorbus, Crataegus (hawthorn), Photinia (syn. Stransvaesia) and Pyracantha.
Fireblight does not infect stone fruits, such as plums, cherries, peaches and nectarines.
Symptoms:
- Blossoms wilt and die at flowering time
- A slimy white liquid may exude from infections in wet weather
- Shoots shrivel and die as the infection spreads down the inner bark
- During the short period of active spread, the outer wood is stained a foxy reddish-brown colour when the infected bark is peeled back
- Cankers (areas of dead, sunken bark) on branches, especially where infected shoots join larger branches
Prune out and burn infections promptly, peeling back the bark to reveal the reddish-brown staining and cutting back 30cm (1ft) to healthy wood in smaller branches, 60cm (2ft) in larger ones. Wipe pruning tools with disinfectant (Jeyes Fluid or methylated spirit) between cuts to avoid spreading the bacteria. Remove secondary, late blossoms before they open.
Hawthorn hedges can be a source of infection.