Doing it Biologically !!!
Opportunities to use Natural Enemies on Landscape
OrnamentalsMichael Brownbridge
Entomology Research Laboratory
University of Vermont
Biocontrol success in greenhouses…
• controlled environment
• closed environment
• once released, natural enemies remain on the crop
Why are there fewer options for landscape ornamentals ?
• environmental conditions more variable, may be sub-optimal
• pests can migrate in from surrounding environment
• natural enemies will head for the food source – may not be on your plants!Few beneficials with proven efficacy
IPM
Sanitation
CulturalBiological
Chemical
Pest management is a
dynamic process:
• Pest outbreaks vary from year to year
• Influenced by location, weather
• Plant variety
• Market
• Clientele
1. Pesticide stewardship important:
• to delay resistance
• limited number of new insecticide registrations; FQPA = net loss
2. Health and safety of staff, general public
3. Environmental concerns
4. Difficult to work nr. schools, residential areas
Why biologicals? Why IPM?
Scouting – knowing what’s going on on your plants!
• Early detection
• More control options
• Better control
• More cost-effective
Bacillus thuringiensis - Bt• Bt kurstaki e.g. Dipel
caterpillars
• Bt aizawai e.g. Xentari caterpillars
• Bt san diego, tenebrionis beetleselm leaf beetle, imported willow leaf beetle;
not viburnum leaf beetle
Viburnum leaf beetle eggs
Prune infested twigs Oct-mid April
Optimizing Bt efficacy:• Select correct strain
• Good spray coverage
• Apply early vs. young larvae
• More susceptible
Less damage, less product, more cost-effective
Insect-parasitic nematodes
Produced by:
Becker-Underwood
Sold through:
AgBio Inc.
Nematodes for slug control
HETEROMASK™
Heterorhabditis bacteriophora
Steinernema carpocapsae
• Effective at 70 – 85° F
• Dogwood borer, banded ash clearwing borer, lilac borer, oak borer, peach tree borer (larvae)
Steinernema kushidai
• Japanese beetle, oriental beetle (larvae)
• Difficult to mass produceSteinernema feltiae
• Fungus gnat larvae in propagation houses
• Will work at temps down to 50 ° F
Atheta coriaria
rove beetle
Predator of shore fly and fungus gnat larvae, pupating thrips.
Excellent control of shore flies obtained when released at 100 beetles per week per 5000 sq.
ft of greenhouse; releases made in early morning or late evening.
Nematode use practices:
• Active vs. larvae; most effective in containers/pots
• Apply to moist soils by drenching
• Apply when host larvae present
• Soil temperature is important
• Compatible with many fungicides and insecticides
• www.agnr.umd.edu/users/ipmnet/nemanurs.htm
Beauveria bassiana
Metarhizium anisopliae
‘Rhizosphere-competent’
Ladybeetles
• Active release?
• Naturally-occurring
feeding on azalea lace bug
nymphs
Green lacewing larvae
Chrysoperla carnea
lacewing eggs
Spider mites
• Rapid reproductive rate
• Short generation time
• Damaging populations build quickly
• Pesticide resistance
• Broad-spectrum pesticides, resurgence
Phytoseiulus persimilis
• good vs. two-spot in greenhouses
• does not work well outdoors in cooler regions
Spider Mite Predators
Neoseiulus fallacis
• wider host range
• works outdoors (strawberries, apples)
• may overwinter outdoors
• use early in infestation cycle
• release onto infested plants
• www.ent.orst.edu/prattp/plant.html
Biocontrol of euonymus scale
• Cybocephalus nipponicus
• Originally from Korea
• Released in NJ on infested euonymus
• Established in infestation sites
Conservation Biological Control
• Conserve naturally-occurring beneficials
• Create an environment that is attractive to beneficials
• Avoid use of broad-spectrum insecticides
Enormous benefits, minimal cost
Habitat manipulation to increase biodiversity
Flowers attract predators and parasitoids; other insects serve as alternate prey/hosts
Use of alternative ground coversUniversity of Maryland, Paula Shrewsbury www.shrewsburylab.umd.edu
• wood mulch on/in place of fabric mat• provides a more favorable habitat for generalist predators• refugia, alterative prey
ground beetle larva
predatory mites
In avocado orchards, mulching increased the incidence and activity of natural enemies and other beneficial arthropods.
Using pesticides
• Create habitats to maintain natural enemies (refugia)
Flowering plants, ivies, vines
• Select and use ‘soft’ or ‘reduced-risk’ pesticides
Short residual activity, narrow host spectrum, IPM
compatible. EPA classification, limited use
restrictions
Bio-derived Products
Minimum-risk pesticides, exempted from registration requirements – even in NY!!!
• E-Rase – Jojoba oil; whitefly control
• GC-Mite – cotton seed and clove oils, garlic extract; mites, thrips
• Hexycide – rosemary and mineral oil; whiteflies?
• Organocide – sesame oil; aphids, mites, powdery mildew
Very little efficacy data available on any of the products. May be phytotoxic – test on a limited number of plants before treating
a whole crop!
Spray Oils and Insecticidal Soaps
• Ultra-Fine Spray Oil (Whitmire)
• Dormant oils
• Synergy Super Fine spray oil emulsion (Griffin)
- micro-emulsion process = remains in suspension for 3 h• PureSpray Foliar 15 (Purespray Green?); Petro Canada
- used in Canada on tree crops, fruits, ornamentals
- pursuing registration in the US
• Olympic Insecticidal Soap, M-Pede
Broad-spectrum, but short residual; often applied at times of year when little natural enemy activity.
Beware of phytotoxicity, esp. on spruces and conifers, after bud-break or in early dormancy.
Neonicotinoid InsecticidesSimilarities:
• Expensive
• Long residual control
• Excellent plant safety, low mammalian toxicity
• Systemic or translaminar movement
• Active vs. piercing/sucking insects
• Variable activity against other pests
• Similar modes of action, risk of cross-resistance
Neonicotinoid Insecticides
Pioneer products: Marathon, Discus, Xenith, Merit
New products: TriStar (Cleary’s) – Acetamiprid
spray application only
Safari (Valent) – Dinotefuranvery water-soluble, readily translocated
Clutch/Arena (Arvesta) – Clothianidin Flagship (Syngenta) – Thiamethoxam
Various formulations for spray or drench application
Other reduced-risk insecticides
• Flagship, Endeavorvery effective vs. aphids (sprays), mealy bugs (drench)
• Conservecaterpillars, leaf-feeding beetles, short residual
Reduced-risk miticides
• TetraSantranslaminar activity vs. spider mites, ovicidal, slow-acting
• Floramitegood for early-season infestations, compatible w. predators, selective
• Hexygonrestricted use label in NY
• Ornamite
Limited n. applications per growing season; resistance management
Products to avoid:
• organophosphates Dursban, Diazinon, Dimethoate
• carbamates Sevin, Furadan
• pyrethroids Talstar, Tame, Ambush (Pounce)
Broad-spectrum, long residual, highly toxic.
Many withdrawn for nursery and residential use; restricted use.
Pest resurgence, secondary pest outbreaks.
www.ent.orst.edu/prattp/pesticides.html for compatibility with N. fallacis
Can you do it biologically?• Take active steps to release and preserve natural enemies
• Create an environment that conserves and encourages activity
• Use reduced-risk pesticides only when necessary in a planned IPM strategy • Will depend on plant species, pest and infestation level, time of year, location and clientele
Thanks to:
New England Grows
Paula Shrewsbury, Univ. Maryland
Carol Glenister, IPM Labs, Locke, NY
Dan Gilrein, Cornell Univ. Cooperative Extension
This presentation is available for download on our website:
www.uvm.edu/~entlab
Click on ‘Recent Publications’