Massachusetts IPM Berry Blast

May 5, 2016

In This Blast
Strawberry Bud Weevil - Clipper
Tarnished Plant Bug
Gray Mold
Mummy Berry
Raspberry Fruitworm

STRAWBERRY
Strawberry Bud Weevil (aka Clipper)

Identification: The strawberry bud weevil is a small, reddish-brown weevil 1/8" long with a long snout. They can be found on blooms and in blossom clusters very early in the season. Larvae white and legless but are rarely seen as they live inside unopened buds.

Damage: In the pre-bloom to early bloom period the clipper is one of the main insect pests in strawberries. The females lay an egg in an unopened flower bud and then clip the stem of the bud causing it to flop over or fall off. Only unopened flower buds are affected. Some strawberry varieties (e.g., Jewel and Seneca), can tolerate a fair amount of bud loss from clipper, causing the remaining fruit to size up more (like thinning peaches). However in high numbers, it can be a problem in any variety. Clipper tends to be a more severe problem along borders of plantings, near woods, hedgerows or stonewalls.

Life Cycle: Strawberry Bud Weevil overwinters as an adult in protected areas outside the field, often in wooded hedgerows, fencelines or stone walls. Adults emerge in late April or early May when temperatures warm to 60˚F and growth begins. Females need a protein meal in order to produce eggs and they will often feed on pollen from strawberry king blossoms. If these have not yet opened they will chew a hole through the petals to get at the pollen leaving a 'shot-hole' look to the flowers when they open. This can be a good cue to look closer for damage. After feeding the females will lay eggs and after larvae are mature and dried buds have fallen to the ground, they will pupate in the soil for the rest of the year. SBW has only on generation per crop year in the Northeast.
Management
Scouting Notes: Scout for clipper by counting the number of damaged flower trusses per meter (yd) of row in several locations in the field.

Threshold: Treat for clipper when you find an average of more than 3 highly damaged flower trusses per meter of row. If the threshold is exceeded, consider treating with one of the labeled materials below.
You may be able to treat only border rows near woods, hedgerows or stonewalls. DO NOT SPRAY INSECTICIDES DURING BLOOM. Generally only one spray application is needed if threshold is exceeded.
(Photos from Ontario Crop IPM websites)

Summary Management Table:

Conventional (PHI)	Organic OMRI listed (PHI)	Cultural Practices
Bifenture 10DF (0) Brigade WSB (0) Danitol 2.4EC (2) Lorsban 4E (21)	⊗ Aza-Direct (0) ⊗ AzaGuard (0) ⊗ PyGanic EC (0) ⊗ Molt-X (0)	Avoid planting near other hosts (e.g., brambles) Control wild hosts nearby (e.g., wild strawberries or wild brambles) Monitor field edges near woods, stone walls or hedgerows first since this is where clipper overwinter Rotate field out of strawberries for 3 years if heavily infested Renovate carry over fields promptly after harvest is complete

*= Restricted Use Material, ⊗= OMRI approved for Organic Production
Not all available formulations are listed. See the current New England Small Fruit Management Guide for application rates and additional information. Read labels thoroughly for application rates and restrictions (REI, PHI, etc.)

Tarnished Plant Bug (For IPM info see http://www.omafra.gov.on.ca/IPM/english/strawberries/insects/tarnished-plant-bug.html)

Identification: The tarnished plant bug (TPB) is a small (1/4”) bronze-colored insect with a triangular marking on its back. The adult form has long legs and long antennae and piercing and sucking mouthparts (like a mosquito). The immature stage, or nymph, is smaller and bright green, resembling an aphid, but much more active.

Damage: Both adults and nymphs feed on the developing flowers and fruit, sucking out plant juices with straw-like mouth-parts. Feeding releases digestive enzymes that causes cell death, distorted growth, and seed damage all of which result in mishapen fruit. This deformed fruit: typically “cat-faced” berries, also called nubbins or button berries is generally unmarketable. While both adults and immatures (nymphs) can be present during strawberry bloom, nymphs cause more damage since they are present in larger numbers.

Life Cycle: Overwintered tarnished plant bug (TPB) adults emerge in the spring, feeding on new buds and shoots of rapidly growing plants including weeds and strawberries. They lay eggs on plant material once the daytime

temperatures average in the mid 60°F or higher. Depending on the temperature the nymphs will hatch in 7- 10 days. Nymphs generally emerge in mid May, feeding on the developing bloom and fruit. Adults and nymphs can both be present in a crop at the same time as a result of overlapping generations, having between three to five generations per year. From fall to winter only adults are present as they prepare to overwinter in dead weeds, leaf litter and under tree bark. Adults emerge in the spring when the temperature reaches 46°F to start the life cycle over again.

Management
Scouting Notes: White sticky traps are available for monitoring tarnished plant bug adults. These traps are used as a indication of when plant bugs begin their activity in the spring and a relative indication of their abundance, not as an indication of when to control this insect as no thresholds have been established for this trap. Immature TPB (nymphs) are sampled by shaking flower trusses over a flat white surface. Thirty flower clusters should be sampled evenly from across the field (typically 6 clusters at 5 locations or 5 clusters at 6 locations).
Threshold: If 4 or more flower clusters are infested with nymphs (regardless of how many) a spray is recommended. A follow-up spray application may be made after bloom if TPB are still present in high numbers (check harvest interval before selecting material).
A sequential sampling system can be used to save time. See https://ag.umass.edu/fact-sheets/strawberry-tarnished-plant-bug.

Actions: If the threshold is exceeded, consider treating with one of the labeled materials below. DO NOT SPRAY INSECTICIDES DURING BLOOM. (Photos from NY IPM and Ontario Crop IPM websites)

Summary Management Table:

Conventional (PHI)	Organic OMRI listed (PHI)	Cultural Practices
Assail 30SG (1) Bifenture 10DF (0) Brigade WSB (0) Captiva (0) Danitol 2.4 EC(2) Dibrom 8EC (1)	⊗ Mycotrol O (0) ⊗ PyGanic EC (0) ⊗ Aza-Direct (0) ⊗ Molt-X (0)	Row covers accelerate development and help avoid injury. Avoid mowing nearby alfalfa when strawberries are in bloom or early green fruit. Tarnished plant bug pressure is often highest in weedy fields or in fields bordered by woody shrubs.

*= Restricted Use Material, ⊗= OMRI approved for Organic Production
Not all available formulations are listed. See the current New England Small Fruit Management Guide for application rates and additional information. Read labels thoroughly for application rates and restrictions (REI, PHI, etc.)

BLUEBERRY

Mummy Berry

Identification: The first symptom of this disease is browning along the major leaf veins on newly emerging leaf clusters. The leaves wilt quickly and bend to resemble a shepherd's crook. A light gray powdery layer of spores develops at the leaf base. These spores go on to infect flowers and fruit. Infected green berries appear healthy but cutting them open reveals a white fungal growth inside. When berries start to ripen, infected berries appear pinkish tan and slightly ridged. They feel rubbery and contain a gray to black fungal mass inside. Infected berries eventually become faded, shrivel up, and fall to the ground. After the fruit skin has weathered off, the berries look like tiny black pumpkins.

Disease Cycle: The fungus overwinters in the mummified fruit on the ground. In early spring, trumpet-shaped mushroom cups produced on the mummies eject windborne spore that infect young shoots. Frost may increase susceptibility of blueberry shoots to infection. Spores are produced on blighted shoots and are carried to flowers by wind, rain, and insects (bees), resulting in fruit infections. Mummies that fall to the ground provide inoculum for the disease in the following year.

mummyberry shoot strike

photo credits: 1) MSU Blueberry Facts 2) eXtension fact sheet 3) NC State Fruit Consortium

Damage: The fungus infects and invades the developing fruit rendering it unmarketable.

Management:
Monitoring: Consult scouting records from previous years to determine if build-up of this disease is indicated. Monitor weather conditions to identify likely infection periods. Scout fields beginning at budbreak for symptomatic tissue. This timing often coincides with Fortsythia bloom.

Control strategies:
Cultural/Biological:

Plant resistant varieties whenever possible. Those that are most resistant to the shoot blighting phase of the disease include Bluejay, Darrow, Duke, Elliot, and Toro. Cultivars that are consistently resistant to the fruit infection phase include Northsky, Reka, Northblue, Bluegold, Bluejay, Weymouth, and Patriot. Resistance to fruit infection appears to be unrelated to resistance to shoot blight, and weather factors can also affect cultivar response to the disease.
Prune bushes to open the canopy to light, air, and spray penetration.
Cultivate beneath plants in fall and again in early spring to disrupt overwintering inoculum.
Apply a 3-4” layer of mulch material over the soil surface in early spring before mushroom cups emerge to create a physical barrier to spore release.

Chemical:

Apply recommended fungicides during the period between budbreak and tight cluster if scouting and weather monitoring indicate risk of infection.
Time fungicide applications closely to frost/freeze events that predispose tissue to infection.
Repeat fungicide applications at recommended intervals if weather conditions are conducive to infection.
Rotate fungicide materials from different FRAC groups to avoid promoting the development of resistant strains of this disease.

Summary Management Table:

Conventional (PHI)	Organic OMRI Listed (PHI)	Cultural
Abound F (0 day phi; Note caution regarding spray near or with equipment also used in apples) Captec 4L (0) Indar 2F (30) Omega 500F (30) PropiMax EC (30) Quash (7) Quilt Xcel (30) Switch (0)	⊗ Actinovate AG (0) ⊗ Double Nickel 55 (0) ⊗ Regalia (0) ⊗ Serenade Max (0)	Use resistant varieties Prune for open canopy Cultivate beneath plants after harvest to disrupt inoculum Mulch in early spring to cover inoculum
= Restricted Use Material, ⊗= OMRI approved for Organic Production PHI - pre harvest interval in days Not all available formulations are listed. See the current New England Small Fruit Management Guide for application rates and additional information.* Read labels thoroughly for application rates and restrictions (REI, PHI, etc.)

RASPBERRY
Raspberry Fruitworm
Identification: The raspberry fruitworm is a small (1/4”) brown somewhat hairy beetle which feeds on the flower buds and leaves of raspberry plants during the spring and early summer. Female beetles lay eggs on the flowers and green fruit. The larvae that emerge are yellowish white, and feed on the fruit, attaining about 3/8” in length.

Damage: The main damage is to fruit by larval feeding between the fruit and the fleshy receptacle. Many of the flowers and fruit can be destroyed by this insect, and the larvae may end up in the harvested fruit, greatly reducing customer appeal. Leaf damage can also occur from adult RFW feeding along the edges of folded leaves as they first emerge. This leaves elongated holes in the leaves as they expand.

(Photos: left, early season foliar damage; middle, larvae inside fruit; right, adult beetle feeding on flower bud. Credit: Washington State University Whatcom County Extension publication IPM for Raspberry Beetle)

Life Cycle: RFW overwinter as adults in the soil emerge in the spring between mid-April and mid-May depending on soil temperatures. The adults feed on leaves, often on the new primocane leaves, but in areas of high populations they will also feed on upper floricane leaves. Adults are then attracted to flower buds and blooms where mating and, subsequently, ovipositing occurs. Larvae (or fruitworm) emerge from the eggs on the flower or immature fruit and begin feeding on the receptacle. The larvae will remain in the receptacle until the fruit is harvested or falls to the ground at fruit maturity in late summer. Pupae are present in the soil in late summer to early autumn. Adult beetles emerge from the pupae in late autumn and remain in the soil until the spring.
Management
Scouting Notes: There is some evidence suggesting that this insect is more of a problem in weedy plantings. If early damage is noted, (e.g., small holes chewed in flower buds and skeletonizing of leaves), cover sprays should be applied prior to bloom. Adults (beetles) tend to be most active and noticeable on plants in the early evening hours. Rebell® Bianco white sticky traps placed at 20 yard intervals on the periphery of the field can be used to monitor adult populations. Check traps weekly.
Thresholds: No thresholds have been established yet for this pest either from visual scouting or trap captures. However, trap captures of over 10 beetles per trap may suggest the need for treatment. If allowed to build up over time, economic damage levels are likely.
Treatment: If significant populations are found, treatment with one of the materials listed below is recommended.

Summary Management Table:

Conventional (PHI)	Organic OMRI Listed (PHI)	Cultural
Assail 30SG (1) Delegate WG (1) Sevin XLR Plus (7)	⊗ Aza-Direct, (0) ⊗ Entrust (0) ⊗ Grandevo DF (0) ⊗ Pyganic EC (0) ⊗ Venerate XC (0) *Incluce adjuvant with Grandevo DF and Venerate XC	Eliminate wild brambles in the vicinity of the planting Eliminate weeds from within the planting Prune for open canopy Use Rebell® Bianco sticky traps to monitor population
= Restricted Use Material, ⊗= OMRI approved for Organic Production PHI - pre harvest interval in days Not all available formulations are listed. See the current New England Small Fruit Management Guide for application rates and additional information.* Read labels thoroughly for application rates and restrictions (REI, PHI, etc.)

Archived IPM Berry Blasts are available at the UMass Extension Fruitadvisor website.
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