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Problem
Areas on Fruit Plants
| Author: |
OMAFRA Staff
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| Creation Date: |
25 July 2005
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| Last Reviewed: |
20 December
2005
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Table of Contents
- Introduction
- Roots
- Trunk and Branches
- Leaves
- Fruit
- Related Links
Introduction
Use the following information to identify the cause of your fruit
tree problems. Examine the damage on the tree and then refer to the
corresponding section. Similar symptoms can result from different
problems. When in doubt, consult a qualified specialist for advice.
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Roots
Roots rotted, fine fibrous roots, bark strips off easily,
discoloured wood underneath.
- root rot fungi, waterlogged soil
- tree planted too deeply
- tree planted in compacted or improper soil
- nematodes
Roots or lower stem have tumor-like growth
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Trunk and Branches
Sunken, discoloured, missing or split areas of bark, often
with cracked edges; pimple-like structures or gum production on bark.
- canker-causing fungi
- bacterial fire blight
- winter injury (especially on the south and west sides of the tree)
- improper pruning
- mechanical wound (lawn mower, etc.)
Bark missing, teeth marks in wood
- field mouse or rabbit feeding
Small holes in bark with evidence of sawdust; tunnels underneath
bark
Cross-section shows brown staining in wood; may have shelf-like
fungi on the bark
- verticillium wilt fungus
- wood decay fungus
- silver leaf fungus
Swollen, dark green to black areas of bark on plum or cherry
Small twigs or entire branches die back; buds are brown inside,
dried up or rotted
- winter injury
- canker-causing fungi
- bacterial blights
- brown rot (peach, plum, cherry)
- borers
Small bumps on bark that are easily removed with a sharp
object
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Leaves
Leaves do not emerge, or wilt, discolour and die
- abiotic injury: winter injury, severe drought
- plant girdled by borers, twine, wire or rodent
- canker-causing fungi
- verticillium wilt
- root rot fungi
Leaves turn black or brown on part of plant and remain attached
- fireblight (apple, pear)
- brown rot (peach, plum, cherry)
Presence of sticky, shiny honeydew covered with black, sooty
mould
- sucking insects such as aphids
- scale
- pear psylla
- sooty mould
Speckled or discoloured; may dry out and turn bronze or brown
- spider mites, European red mite
- leafhoppers
Covered with white powdery mould
Puckered, contorted, stunted appearance
- peach leaf curl
- aphids
- pear psylla
Twisted, cupped, yellow, strap-like appearance
Presence of olive-green to black, felt-like patches
Edges dry and brown
Small orange, grey, tan, or brown spots on leaves; sometimes
dried tissue falls out, leaving holes
- frog-eye leaf spot on apple
- cherry leaf spot on cherry
- cedar apple rust
Leaves are eaten
- large holes: caterpillars
- green parts eaten, only veins remain: skeletonizers (e.g. pear
slug, caterpillars)
- rolled or webbed together: tent caterpillars, leafrollers
- hollowed-out areas: leafminers
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Fruit
No fruit development
- winter injury, frost injury
- poor pollination
- excessive fertilization
- immature tree
Fruit drops early
- normal June drop due to excessive fruit set
- insect infestation inside fruit: curculio, maggots, caterpillars
- carbaryl insecticide used just after bloom
- excessive pest injury to leaves (tentiform leafminer)
Blemishes
- half-moon scar: plum curculio
- sunken dimples: apple maggot on apple or prune (Italian or Stanley);
plant bug on apple, pear, peach; cherry maggot
- holes in fruit, may have sawdust-like frass: codling moth on apple
and pear; oriental fruit moth on peach
- tiny brown knobs which can be scraped off easily: scale insects
- rotted, tan to dark brown spots: fungus diseases - black rot on
apple, brown rot on peach, plum and cherry
- dark olive-green to brown felt-like patches, sometimes skin cracks:
apple scab, pear scab
Fruit rot on the tree or after harvest
- soft, watery rot covered with white and black whisker-like mould:
Rhizopus rot (peach, plum, cherry)
- soft, brown rot covered with greyish-brown, velvety mould: Brown
rot (peach, plum, cherry)
- firm, dark brown, target-like rot: Black rot (apple, pear)
- watery, tan, sunken rot with blue-green and white tufted mould:
Penicillium rot (apple, pear)
Small, poorly developed fruit
- Excessive fruit set
- Reaction to nearby feeding of aphids
- Pear psylla or other sucking insects
- Cedar apple rust or quince rust infections
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Related Links
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For more information:
Toll Free: 1-877-424-1300
Local: (519) 826-4047
E-mail: ag.info.omafra@ontario.ca
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