Brown rot is a fungal disease of tree fruit, caused by the fungi Monilinia laxa and M. fructigena. The two fungi are very closely related and indistinguishable to the naked eye. M. laxa more commonly causes blossom wilt on pears and stone fruit, and a specific form, M. laxa f. sp. mali is restricted to apples. M. fructigena can cause

A fungal disease that can affect apples, pears, plums, cherries and some related fruit and ornamental trees, causing a brown, spreading rot in the fruits, often with light brown pustules of spores visible.

Many fruit trees and their ornamental cultivars are affected, including apples, pears, plums, cherries, nectarines, peaches, quinces and apricots.

Rotting fruit are found from mid-summer onwards.

You may see the following symptoms:

• Brown rot in the fruit, spreading out from wounds, especially those made by birds, codling moth and apple scab infection
• Infection can spread between touching fruit in a cluster
• Affected fruit either fall, or remain hanging on the tree in a mummified state
• Buff-coloured pustules of the causal fungi on the fruit surface, often in concentric rings. Usually seen under wet conditions
• At flowering time the same fungi cause blossom wilt, where blossoms and leaves on fruiting spurs turn brown and shrivel
• Severity varies greatly from year to year, depending on weather conditions at flowering

Non chemical control

• Minimise carry-over of the pathogens by removing and disposing of all brown rotted fruit promptly. To dispose of fruit, you can bury them at least 30cm (1ft) below the soil surface, or put them in the local council
  Plant-based waste that is suitable for composting, such as dead leaves, clippings from pruning or grass mowing and discarded annuals. Many local councils have green waste recycling schemes if home composting isn't an option.

  green waste (although check first as some councils will not accept large volumes of rotting fruit). Do not allow rotted fruit to remain on the tree
• Brown rot infects through wounds, especially those caused by birds, so if possible, net to reduce bird damage
• If practical, prune out and dispose of infected spurs and blossoms to reduce the amount of fungus available to infect fruit
• The plums ‘Czar’, 'Jefferson', ‘Ontario’ and ‘President’ have some resistance

Chemical control

No fungicides are available to amateur gardeners for the control of brown rot.

Download

Fungicides for gardeners (Adobe Acrobat pdf document outlining fungicides available to gardeners)

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Chemicals: storing and disposing safely

Fruit becomes infected through wounds. Affected fruits mummify and may remain hanging on the tree, and where they touch the

Bark is the outermost layer of woody plants (trees, shrubs and woody climbers). It is several cells thick and provides protection against physical damage, disease and environmental stresses. Bark comes in a wide variety of colours and patterns, and these can help gardeners when identifying plants. The fissures and crevices of bark on older plants also creates valuable habitat for many garden creatures as well as lichens and small plants.