Pest Control Action Plans

BFF ELDERBERRY (EB) RUST ACTION PLAN

Goal: To prevent elderberry (EB) rust from damaging elderberry canes and leaves:

1. Education so we know what we are looking for and when

2. Prevention strategies

3. Control strategies if prevention is not enough

4. Prevent successive generations.

MANAGEMENT STRATEGIES:

1. Education (Goal 1) – understand EB rust, and where/when it will show up. Elderberry rust is a fruit crop disease where scabbed or distorted bright yellow or orange pustules hang from or are attached to leaves and cane stems. Leaves become deformed and develop brown, necrotic spots on the upper surfaces and powdery yellow growths beneath. Infected twigs also become deformed.

The pathogen overwinters mostly on fallen leaves and in twig lesions. New infections may not develop until late spring or early summer. Secondary infections begin developing about 1 month later during wet weather. Wind spreads late summer spores. Infection can occur during wet periods of 8-12 hours. One can apply protective foliar sprays (bacillus pumilus) before infections occur but we have not needed to use any. (Growing Organic Orchard Fruits, pg 347 and What’s Wrong With My Fruit Garden, pg 289).

In 2015 we first spotted EB rust on May 20 in all EB rows 27, 33-35. It was cut with pruners and put into garbage bag. We monitored again on 5/27, 6/1, 6/3,6/12, and 6/16 and removed infected leaves and canes each time. This management controlled it very well. We did not see any EB rust the rest of the season/year.

2. Ground level irrigation system. All bacteria/most fungi need a thin layer of moisture on foliage to gain access/infect plants. By watering the soil not the foliage, risk of EB rust is reduced. (Goal 2, 4)

3. Plant polycultures. Although we have EB in rows, the rows are separated by 12 feet of grasses, weeds and white dutch clover ground cover. Row 27 is separated from Rows 33-35 by rows 28-32 which are planted to blueberries and black currants. (Goal 2, 4)

4. Clean sanitation in EB rows #27, 33-35: In the Fall, EB are pruned using a string trimmer and cutting canes off at about 2-4” above ground level. Removal of these pruned canes in the Fall will minimize disease spread the following year. (Goal 2, 4).

5. Monitoring and removing rust growths, affected leaves and twigs: In mid-May-June, start monitoring EB plants/foliage closely, by walking the row and carefully looking at each plant. The yellow or orange growths may be hard to see. Wear latex gloves and, with a pruners, carefully cut the affected growth, twigs and leaves from the cane, trying not to drop spores when moving. Place immediately into garbage bag that will be disposed after all monitoring for the day. Continue monitoring weekly until you do not see any more EB rust. (Goal 3, 4)

Wash with hot water and sterilize pruners with hydrogen peroxide poured over pruners immediately after use. Let air dry with pruners open. Put away when dry.
Dispose of your gloves into the garbage bag.
Tie garbage bag shut, bring down to the garage, and it will go into WVLC dumpster.
Wash your hands and arms with soap and hot water.

6. Keep records of all activities and observations on Pest Monitoring Log.

BFF ERIOPHYID MITES ACTION PLAN

Goal: To prevent eriophyid mite damage to elderberry plants and fruits

Reduce overall amount of mite presence in elderberries to reduce damage
Disrupt mite life cycle.
Prevent overwintering of mites.
Prevent mites from spreading to other fruit varieties.

MANAGEMENT STRATEGIES:

1. Education (Goal 1-4)

Know what mite damage looks like (since they are microscopic); see photos on pg 143 What’s Wrong with my Fruit Garden; pg 185 Tree Fruit Field Guide; and
Understand powdery mildew (Podosphaera leucotricha or clandestine, Sphaerotheca pannosa), symptoms, spreading conditions, prevention and management strategies

Eriophyid mites are microscopic pests that cause cupping and crinkling of the foliage and can destroy florets and young fruit in severe infestations. Little is currently known about this pest, but they are believed to overwinter under buds and bud scales on above-ground portions of the plant and are therefore easily and unknowingly spread by transporting dormant cuttings for propagation. 2013 winter research in Wisconsin showed that nodes 4 to 6, located near the terminal growing point of last season’s growth, had the greatest average numbers of mites on buds. Terminal buds and those at nodes 12 and 13, located near the soil surface, had the fewest mites. [Warmund, M.R. and Amrine, Jr., J.W. (2015). ERIOPHYID MITES INHABITING AMERICAN ELDERBERRY. Acta Hortic. 1061, 155-159 DOI: 10.17660/ActaHortic.2015.1061.15].

2. Scouting: Use a magnifying glass, 6” square of white poster board or tray and a short stick. Hold the tray under an EB branch and tap on the branch with the stick. You may collect various types of insects, including mites, that would be hard to spot otherwise. Let Jim and Joyce know. Record monitoring activity on Pest Monitoring Log. (Goal 1-4)

3. Start spray with Stylet Oil pre-bloom on leaf surfaces (3-6 qt/100 gal. or 1.5 qt/15 gal water) and continue every 10 days to three weeks depending on the level of disease pressure. For now, we will try once every 2 weeks. Use higher rate or shorter spray interval when disease conditions are severe. This is also being used for powdery mildew management. (Goal 1-3)

4. If observe mite damage, cut affected canes, leaves and/or parts of cymes. Place refuse in garbage bag for proper disposal. Bring closed bag to garage when done. Use latex gloves (also put in garbage bag) and wash pruners with hot water and rinse with hydrogen peroxide. Air dry pruners. Record use and pruners cleaning on Input Application Log.(Goal 1-4)

5. In the Fall, prune all canes at 2-4” above ground level with string trimmer with brush cutting blade. Remove canes from field (pile is maintained outside by mulch area. (Goal 1-4). Canes are chipped and fully composted.

6. Keep records of all activities and observations on Pest Monitoring Log or Input Application Log (Goal 1-4).

BFF PLUM CURCULIO ACTION PLAN

Goal: To prevent plum curculio beetles from damaging plum fruits:

Prevent adult males and females from eating fruit when emerging from pupae stage;
Prevent adult females from laying eggs during petal drop and 30 days thereafter;
Prevent successive generations of beetles during season;
Reduce overall numbers of plum curculio.

MANAGEMENT STRATEGIES:

1. Education (Goal 1,2,3,4)

Know what the beetle looks like; see Tree Fruit Field Guide, pg 82 for photos.
Know what the damage looks like- crescent shaped damage made by adult female as she lays her eggs; white crusty sap exudate;
Understand life cycle of plum curculio beetles, temperature needs, etc: 1) Pupae hibernation mid-July-mid-August in soil within 1 inch of surface; 2) Adults emerge from pupae stage in the Spring after 3 days of 60’s-low 70’s°F weather; males emerge first followed by females a few days later;3) Eggs – once mating takes place, the female has a pre-oviposition period of a few days before she begins depositing eggs in fruit; this causes the crescent shaped damage on the skin of the fruit; 4) Larva hatch and eat inside the fruit (early June through mid-July), causing most of the fruit damage; this lasts 2-3 weeks, growing from 1mm to 6-9 mm in length; as adult larvae, they burrow into 1-2 inches into the soil and construct a pupae chamber. It is 12-16 days before the larvae pupate after leaving the fruit. 2-3 weeks are spent in the pupal stage before becoming adults, with several more days before they harden and emerge from the ground; 5) The progeny of the adults that emerged in the spring appear as adults in July-August. They fly to the plum trees and feed on developing fruits but do not reproduce in most instances. They are the adults that find hibernation sites to overwinter. They can hide in the soil during the day.

2. Clean sanitation in orchard undergrowth (Goal 1,3, 4)

Clean up prunings;
Mow July through October (until <60° days);
There is not much we can do about the woodland area on the south side of the field.

3. Monitor Spring air temperatures so know when optimal temperatures are reached. It can coincide with shuck split stages on fruit. Temperatures needed are sustained warm temperatures day and night in the 60-low 70’s°F (Goal 1).

4. Monitor and capture PC adults with pyramid Tedders and trunk traps in Spring (Goal 1,2,3,4)

Use traps on the south area closest to the woods (border rows); place trap under the dripline/canopy of the tree about 1 meter from the trunk of the tree; put in place by mid-bloom of the earliest cultivar (Black Ice and Toka);
Monitor traps 2-3x/week (Monday, Wednesday and Friday) – record date, number of plum curculios caught in each trap, and trap location – they will be numbered. Convert the # of plum curculios from “X” number of traps after “Y” number of days. Example: 15 plum curculios from five traps during a two day period – 15 divided by 10 (5 traps x 2 days) = 1.5 plum curculios/trap/day.
Clean traps as needed, especially of other critters and spider webs. Keep grass and other debris away from the traps. Bare soil under the traps is recommended. Clean traps thoroughly before storage.

5. Be observant of crescent shaped damage on developing fruit (Goal 3,4).

Remove damaged fruit and dispose of by putting in tightly shut plastic bag for trash can for dumpster disposal.
Pick up damaged fruit from the ground. This eliminates food and eggs.
Note where (N or S, or tree variety) damage is observed and fruit removed.
Report damage to Jim or Joyce.

6. Plant garlic under trees in grid with 2 concentric circles. (Goal 2, 3,4)

Cut tops to seed more garlic so eventually have a carpet of garlic under each tree. Idea from Fedco Catalgo – 2016.

7. Spray garlic spray (blended up garlic cloves with water, filtered). (Goal 2, 3, 4)

Dilute the garlic concentrate it with water in sprayer at rate of 1 cup garlic to 5 gallons water. Spray when traps show increasing numbers of plum curculios.

8. Remove dropped and damaged fruit during spring and summer prior to harvest (Goal 3,4).

9. Keep records of all activities and observations on Pest Monitoring Log and/or Plum Curculio Trap Log(Goal 3,4).

What has not worked to date: We tried spraying Marrone BioInnovations VENERATE XC Bioinsecticide (OMRI Listed) when adults are active and prior to the start of oviposition. (Goal 1,2,4)

Repeat applications on a 4-7 days interval until adults are no longer active and developing fruit is no longer susceptible to damage. Rotation or tank-mixing with other insecticides labeled for plum curculio is recommended. Sufficient water and spray equipment should be used to ensure complete coverage of foliage and developing fruit. Proper timing of application targeting newly hatched larvae, nymphs or immature pests is important for optimal results. 3 cups per 15 gallons. This product was expensive and did not control PC despite repeat applications.

BFF POWDERY MILDEW ACTION PLAN

Goal: To prevent powdery mildew damage to elderberry fruits

Reduce overall amount of fungal inoculum present in field
Disrupt disease cycle by preventing spores from overwintering
Prevent spread of fungal spores during the growing season

Management strategies:

1. Education (Goal 1-3)

Know what powdery mildew looks like; see photos on pg 143 What’s Wrong with my Fruit Garden; pg 185 Tree Fruit Field Guide; and
Understand powdery mildew (Podosphaera leucotricha or clandestine, Sphaerotheca pannosa), symptoms, spreading conditions, prevention and management strategies

Powdery mildew is a fungus that attacks young leaves and shoots. Infections appear as white patches of powdery growth on either side of the leaf or on the terminal end of shoots. Severely infected leaves curl upward or blister but eventually drop as infection progresses. Towards the end of the season, small, black fungal bodies (cleistothecia) are visible within powdery mildew colonies. The fruit is affected with a white coating and is shrunken and cannot be sold. In EB, only part of the cyme may be affected or the entire cyme may be affected.

Disease cycle: Conidia (asexual spores) are produced throughout the growing season, typically beginning within 3-7 days of initial infection. Spores are carried by the wind to spread infection. Ascospores (sexual spores) form at the end of the growing season and overwinter in plant debris.

Favorable Conditions: Powdery mildew prefers warmth (68-85 ° F) and humidity of 75%, but can grow in less favorable conditions at a less rapid rate. Spores are resistant to cold and drought. Reduced air flow can increase rate of infection.

Powdery mildew affects many fruits, including elderberries and some varieties of black currants. We dug out all Consort variety black currants after they consistently showed with powdery mildew problems. This has solved powdery mildew problems in our black currants. We still have a problem in most varieties of our elderberries, but especially Adams, York, and Johns (not Nova, Bob Gordon or Ranch).

2. Reduce humidity levels on leaves by maintaining an open canopy and good air movement. Plants are planted 4 feet apart and cut back to ground level each fall. All canes are removed. (Goal 1)

3. Start spray with Stylet Oil pre-bloom on leaf surfaces (3-6 qt/100 gal. or 1.5 qt/15 gal water) and continue every 10 days to three weeks depending on the level of disease pressure. For now, we will try once every 2 weeks. Use higher rate or shorter spray interval when disease conditions are severe. Stylet Oil is also being used on EB for mite control and may help with EB rust. (Goal 1-3)

4. Weekly scouting/monitoring of elderberries for signs of powdery mildew on leaves after flowering. Record on Pest Monitoring Log. Let Jim and Joyce know. (Goal 1,3)

5. If observe powdery mildew, cut affected leaves and parts of cymes. (Goal 3,4). Place refuse in garbage bag for proper disposal. Bring closed bag to garage when done. Use latex gloves (also put in garbage bag) and wash pruners with hot water and rinse with hydrogen peroxide. Air dry pruners. Record use and pruners cleaning on Input Application Log.(Goal 1-3)

6. If powdery mildew shows up later in the season when fruit is ripening, spray affected fruit with organic milk once per week. The recipe is 1 part milk:10 parts water or 2 gallons milk:20 gallons water. It doesn’t matter if milk is whole, 2% or skim. Record use on Input Application Log. (Goal 1,3)

7. Keep records of all activities and observations on Pest Monitoring Log or Input Application Log (Goal 1-3).