The Online Gardener's Handbook
Chapter 5: Fruit
Table of Contents
- Pear Slugs
- Peach Tree Borers
- Brown Rot
- Black Knot
- Cherry Maggots
- Leaf Spot
- Learn More
In this chapter, a description of various pests of cherry will
be provided along with suggested management options. These management
options will not include the use of pesticides. Some biopesticides
and certain reduced risk pesticides are still available to the homeowner
for controlling weeds and pests in lawns and gardens. For more information,
refer to Chapter
2 of this handbook and the Ministry
of the Environment's website. For suggestions on managing specific
weeds and pests, consult local horticulturalists, Master
Gardeners or your local garden supply centre.
NOTE FOR TREE OWNERS: There is an exception under the ban that
allows you to hire a licensed exterminator authorized to use commercial
pesticides to maintain the health of your tree. This exception applies
only to pests that threaten the tree's health. For example, the
exception cannot be applied to a pest that impacts the quality of
the fruit but will not kill the tree itself. To obtain this exception,
licensed exterminators are required to obtain a written opinion
from a professional tree care specialist that a pesticide is necessary
to maintain tree health. For more information, contact the Ministry
of the Environment.
Note that many fruit trees can tolerate some damage, particularly
to the foliage, without suffering lasting impacts. Pest descriptions
below include suggestions for cultural controls however in many
situations these may not be necessary.
For information, see Apples.
Pear slugs are the larvae of sawflies and are not true slugs. For
more information, see Pears.
Peach Tree Borers
Peach tree borers attack peach, nectarine, apricot and sometimes
plum and cherry trees. For more information, see Peach.
Brown rot is a fungus that attacks various parts of the trees.
For more information, see Apricot.
Black knot affects plum and sometimes cherry. For more information,
Cherry maggots are related to apple maggots. The small adult fly
lays eggs on developing fruit in late spring and early summer and
the maggot tunnels into fruit, causing it to be small and misshapen
and to fall prematurely. The maggot is yellowish-white, legless
and has two dark mouth hooks. Both sweet and sour cherries are attacked.
A cherry crop infested with maggots is not worth harvesting.
Because the insects will overwinter in the soil under the tree,
gather infested fruit and discard it in the garbage or bury it at
least 60 cm deep. Encourage your neighbours to do the same.
Leaf spot if a fungal disease that often occurs on sour cherry,
but rarely on sweet cherry. Many small, red-purple spots first appear
on the leaves, holes then develop, and the leaves eventually yellow
and drop. The tree is weakened if this happens over successive years.
Rake up and destroy infested leaves as they fall to reduce the
level of overwintering of the disease.