Pests of Specific Crops

Pest Description
Chemical Control
(rate per 100 L water; or per
unit area if indicated)
Cultural Management
PRUNUS - FLOWERING CHERRY, PLUMS, etc. (For Commercial Orchards -
See BCMA Tree Fruit Production Guide)
Diseases:
Bacterial Canker, Blight, Blast, Leaf Shot-Hole and
Spot (Pseudomonas syringae pv. syringae): This
bacterial disease is very damaging at the Coast
in cool, wet springs. It causes cankers,
exudation of gum and dieback of girdled
branches. Gumming occurs at margins of
cankers in spring, usually after a rain. Under
wet conditions, numerous leaf spots are caused
by rain-splashed bacteria. Spots often drop out
leaving a “shot-hole”. Blossoms and new
shoots may brown off completely giving a
“blasted” appearance. New infections cease
once weather turns warm. See General Disease
Management: Bacterial Blight / Canker, Chapter 9.
Brown Rot (Monilinia spp.): This fungal disease
causes blossom blight and dieback of new
shoots in late spring, followed by fruit rot in
summer. Fruit turn brown during ripening,
later becoming mummified. Dead blossoms
and fruit exhibit a brown, fuzzy mould in wet
weather. The fungus overwinters on
mummified fruit and in small cankers on
infected twigs and at the base of buds. The
disease is most severe in warm, wet conditions.
In Coastal areas, symptoms tend to overlap
with those of bacterial canker (see above),
although brown rot infection tends to occur at
warmer temperatures.
Cherry Leaf Curl or “Witches’ Broom” (Taphrina
cerasi): Large, broom-like tufts develop on
branches at blossom time. These branches have
few flowers and leaf out earlier than other
branches. The brooms do not bear fruit and
they get larger each year.
Cherry Leaf Spot (Blumeriella jaapii; anamorph
Coccomyces): Brown to purple leaf spots;
smaller on sour cherry than on sweet cherry.
Large areas of leaves may be killed. Spots often
drop out leaving a shot-holed appearance.
Spots may also occur on fruit stems causing
drop. White spore masses of the fungus appear
within the spots. Common in the Interior but
rarely occurs at the Coast.
COPPER SPRAY 50: 600 g
Apply prior to fall rains and
again when the majority of
leaves have fallen.
Recommended to apply
additional sprays immediately
following pruning or grafting.
Copper may cause leaf spot if
applied under cool, cloudy
conditions. To reduce injury, use
the high rate for fall and delayed
dormant applications and the
low rate in the growing season.
Obtain stock from sources
believed to be free of
disease.
‘Royal Ann’, ‘Bing’,
‘Lambert’ and ‘Van’
cherries are highly
susceptible. Use Mazzard F-
12-1 rootstock for cherries.
Disinfect pruning tools
between trees. Eliminate
old, infected cherry trees
from vicinity of fields
where Prunus nursery stock
is being grown.
Apply at pink-bud stage. If wet weather occurs at this time,
repeat sprays at 50% bloom and full bloom:
BOTRAN: 1.75 kg/ha (peach)
BRAVO 500: 5-9 L/ha
CAPTAN 80-WP: 3.75-4.5 kg/ha
FUNGINEX DC: 75 mL
KUMULUS DF: 750 g
ROVRAL WP & WDG: 1.5 kg/ha
TOPAS 250E: 500 mL/ha
Apply in all regular sprays except blossom:
BORDEAUX: 200 g COPPER 53W + 400 g HYDRATED LIME
Apply copper under fast drying conditions.
Ornamentals only: DACONIL 2787F: 250 mL or DACONIL
Ultrex: 150 g
Remove mummified fruits from tree and ground during
dormant season. Prune out cankered twigs.
Refer to the Ministry’s Tree Fruit Production Guide for
additional chemical control options.
See Peach Leaf Curl, below.
Prune out “witches’
broom” 30 cm below point
of infection. Remove old,
infected trees from the
nursery.
COPPER SPRAY 50: 200 g + HYDRATED LIME: 400 g
EQUAL 65WP: 2.25 kg/ha
FERBAM 76 WDG: 175-200 g
KUMULUS DF: 750 g
TOPAS 250E: 500 mL/ha
Make the first application at petal fall. In the 3 weeks prior to
harvest make a 2nd and 3rd application at a 7-10 day interval.
30 • Pests of Specific Crops Nursery Production Guide