Lucy Bradley Urban Horticulture Specialist Thanks to Steve Bambara, Charlotte Glen, Craig Mauney and...

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Lucy BradleyUrban Horticulture Specialist

Thanks to Steve Bambara, Charlotte Glen, Craig Mauney and Debbie Roos for content & images

Best Management Practices

Lucy BradleyUrban Horticulture Specialist

Best Management PracticesAnnih

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Lucy BradleyUrban Horticulture Specialist

Best Management Practices

It’s called

the

Food Chain!

Keep Plants Healthy

Right Plant, Right Place Proper Planting Appropriate Water Encourage natural enemies Avoid Stress

Stress Reduces photosynthesis Reduces growth Attracts pests

Stressors: Too dry or wet, Too high or low soil pH, Too low or too high nutrients, Planted too deep Compact soil

Good Offense

Drought stressed plants ‘glow’ and

‘scream’ to insects

Biodiversity

Systems Approach

Pests indicate problems

Solution addresses

the underlying problem,

not just the symptom.

Monitor

Identify

Evaluate

Choose

Implement

Image from http://www.regina.ca/AssetFactory.aspx?did=690

What is normal seasons of the year stages of life?

What problems are typical?• Insects?• Diseases?• Abiotic?

Learn to recognize the various stages of their life cycle

IPM uses all possible methods

to keep damage below an acceptable level:

Acceptable level varies

between plants & people

complete eradication is not the goal!

Environmental Factors we can manage: Soil management

Plant selection

Planting times and spacing

Watering and mulching

Sanitation

Crop Rotation

Trap Crops

Environment

Pathogen

Host

Disease Triangle Prevent disease by removing a factor

Environmental Factors we can manage: Soil management

Plant selection

Planting times and spacing

Watering and mulching

Sanitation

Solarization

Crop Rotation

Environment

Pathogen

Host

Disease Triangle Prevent disease by removing a factor

Soil Soil ManagementManagement

Soil test

Manage nutrients & pH

Add organic matter

Alleviate soil compaction

Water appropriately

Mulch

To till or to till To till or to till notnot B

enefitsD

isrupts life cycle of pests & beneficials

Can expose pests to predators & the elements

Till before planting to manage weeds that harbor armyworms, cutworms, plant bugs and aphids

Till in fall to destroy overwintering sites for flea beetles, corn borers, squash bugs, etc.

Drawbacks

Can lead to compaction

Erosion

Plant SelectionPlant SelectionC

hoose varieties adapted tol

ocal climate & site conditions:

soil type

drainage

sun exposure

Image from the Grumpy Gardener, Southern Living

Select Resistant Select Resistant CultivarsCultivars

Many varieties of Crape Myrtle are resistant to

powdery mildew

Restrict insect movement,

feeding or reproduction

size, shape, color, leaf hair, cuticle thickness, and natural chemicals

(attractants & repellants)

Less attractive to pests.

Dark green leaves are less attractive than yellow green.

Produce compounds that deter pests – e.g. pyrethrum is from African chrysanthemum blooms.

Tolerance for damage

Select Healthy Select Healthy PlantsPlants

Purchase

well cared for

disease free,

insect free plants

from reputable sources

Plant SelectionPlant Selection

Select plants

that will be able to grow to their full mature size in the allotted space.

Power line pruning, photographed by flickr user Justin Berger]

Planting Planting DatesDatesAvoid heat and cold stress

Avoid known pest problems by planting early or late.

Plant squash early to avoid vine borers which become active in June

Shift Planting Shift Planting DatesDates•Plant winter squash before June 1 to give rind time to harden before the pickleworm arrives.

Shift Planting Shift Planting DatesDates•Plant corn early to avoid ear worm

•Plant crops susceptible to nematodes early while soil is cool

•Plant late to avoid rot and improve germination

PlantingPlanting

•Direct seeded plants•Require correct conditions to emerge and grow quickly

•Transplants may be more resilient

Plan for mature size

Allow air flow between plants to promote drying & prevent disease

Allow adequate space to minimize:

competition for Water, Nutrients, & Light

Habitat for pestsProper spacing depends on mature size of plant – most plants do best when leaves just touch at full size

InterplantingInterplantingA

void placing all plants of one kind together

Alternate groups of different plants within rows or patches

Flowers help attract beneficials

The strong scents of herbs can confuse insects

To reduce disease, avoid wetting leaves

Most fungal leaf diseases require 4 hrs + of continual leaf wetness to infect

Water fan sprinklers spray water in the air, wetting foliage

Drip irrigation delivers water through pipes directly to the soil

Weed Management

Prevents annual weeds from coming up

Reduces stress on plants

Keeps soil cooler Conserves moisture

Avoid ‘Volcano’ mulching!A 3” layer of mulch is good around trees and shrubs –

Manage weeds

Eliminate habitat for pests & diseases

Remove plant debris, (fallen fruit, twigs, and leaves)

Prevents insects and diseases from overwintering

Pick up twigs under pecan trees before eggs hatch and larva enter soil

Prepare soil for planting, water, then cover with clear, 1- 4 mil thick plastic for 5-6 weeks in the hottest part of the summer.

Helps manage:

weed seeds,

pathogens,

nematodes

Avoid planting crops in the same family in the same location multiple years.

Crop RotationCrop Rotation

Manual

Traps

Exclusion

Sanitation

Environment

Pathogen

Host

Disease Triangle Prevent disease by removing a factor

Manual: HandpickingManual: Handpicking

Handpick bagworm ‘bags’ in winter – removes eggs

Inspect plants for

egg clusters, beetles, caterpillars, or other pests.

Squash or drop them in sudsy water.

ManualManualM

owing

Pruning

Shaking

Flaming

Vacuuming

Water sprays

TrapsTrapsM

ost insect traps are most useful for detection and monitoring

Be sure that you are not attracting more pests into an area!

Pheromone traps have chemicals that mimic mating hormones

Not much evidence to support the value of Japanese Beetle Traps

TrapsTrapsT

here are many kinds –

must get right type for pest

Bait traps

Japanese beetle traps

Pheromone traps

Slug and snail traps

Sticky boards

Trap Crops

Water Traps.

Trap Crops

Plant a crop more attractive to pests than your desired crop

Then treat the pest on the infested decoy plant

Different crops attract different pests:

Mustard – Striped Flea Beetle &

Harlequin bugsB

lue Hubbard squash-

Striped Cucumber BeetleY

ellow Rocket - Diamondback Moth

Mixed results Stinkbugs on the Trap Crop Sesbania Rostrata

http://www.agnet.org/images/library/nc125d2.jpg

ExclusionExclusion•cut worm collars,

•floating row cover,

•netting,

•mulches,

•sticky barriers (trunk bands),

•copper strips,

•bagging fruit, Kaolin

•plastic lined trenches and

•fencing

A cardboard or foil collar can protect young vegetables from cutworms

Floating row covers can keep flying adult insects from laying eggs on vegetables

Clay material ground to uniform size Forms a barrier on plant surface to

insect and disease Must be sprayed ahead and every 7-

10 days Washes off easily, must be reapplied

after rain Must be agitated to keep it suspended

Sanitation

Prune out infected twigs and rake fallen twigs and leaves to prevent insects and diseases from overwintering.

Canna Leaf Roller can be managed by cutting off old foliage in winter

Rake up fallen leaves from plants showing leaf spot and other disease symptoms.

Beneficial Animals & Insects Predators

Larva &/or adult eats pests One predator eats many pests Varied diet

Parasitoids Egg is laid on the pest, immature consumes

pest as it matures One parasite (sometimes many parasites)

eat one pest. Very selective

Beneficial Diseases Bacteria, virus, fungi, nematodes, protozoa

Environment

Pathogen

Host

Disease Triangle Prevent disease by removing a factor

Learn to recognize all life stages of beneficials

Diverse landscapes encourage beneficials – plant many different types of plants, including flowers

Strive for a balance of good and bad insects.

Hoover Fly adults look like bees or wasps

Hoover fly larvae look like small slugs or caterpillars – voracious aphid eaters

Beneficials

Attract and Conserve Plant small flowered crops

Carrot family Daisy family Mint family

For example: Catnip, caraway, dill, fennel, hyssop, lemon balm,

parsley, rosemary, thyme, yarrow, etc.

Purchase & Release

Predators

Creatures that catch, kill and eat insects

Most like a wide variety of prey, & consume numerous prey over their lives

Insects, spiders, lizards, and frogs

Assassin BugsPrey:•aphids, •caterpillars,•beetles, •leafhoppers, & •other insects

They do not like to be handled.

Big-eyed Bugs

Prey:•spider mites,•thrips, •aphids , and•other insect eggs

Damsel Bugs

Resemble assassin bugs

Prey:•Aphids,•leafhoppers, •mites, and• caterpillars

Green (or Brown) Lacewingsaka “Aphid Lion”Prey on: Soft-bodied insects –•aphids, •mites, •insect eggs, •thripes, •mealybugs, •immature whiteflies,• small caterpillars 200+/week

larva

adult

Ground Beetles

Large, dark, and sometimes metallic, they feed along the ground, especially at night.

Prey:• soft-bodied insects

larva

adult

larva

Prey:•aphids, •mites, •Insect eggs and •small insects.

Minute Pirate Bug

Prey:• thrips, • spider mites,• aphids, and • small insects.

larva

Praying MantidsEat relatively few insectsin the garden.

Predaceous Stink Bugs

Many stink bugs are pests, however, both as adults and as colorful nymphs predaceous stink bugs are predators. Prey:•beetles and •caterpillars

Predatory Flies

Prey:• thrips, • mites,• aphids, and • insects larva

Long Legged Fly

Robber Fly

Predatory FlySyrphid Flies

larva

The harmless adults resemble

bees,but the small

larvae consume many

aphids.

adult

Predatory Mites

Move rapidly to catch and eat their plant-eating counterparts.They are often white, tan, or orange.

Prey:•spider mites•thrips, •fungus gnats •other small insects and•insect eggs

Soldier BeetlesAdults resemble firefliesand are attracted to milkweed, hydrangea, and goldenrod.

Prey:•caterpillars,•mites, •grasshopper eggs, and•small beetles

Wasps & Hornets

Though often considered pests, these insectsfeed heavily on•caterpillars, •flies and •other •soft-bodied insects.

Parasitoids

Beneficial insect lays its eggs on a pest. When the eggs hatch, they consume the pest.

One (or sometimes many) beneficial(s) consumes only 1 pest

Very selective about host.

Parasitic Wasps

Tiny Micro- and mini-wasps sting and lay eggs in• caterpillars, •Aphids, or •insect eggs.

The larvae consume their prey from within.

Aphidius wasp ovipositing in aphid

Scelionid wasp parasitizing stink bug eggs

Braconid Wasps

 

On hornworm caterpillar

Trichogramma Wasps

 

On hornworm egg

Tachinid Flies

Heavily bristled Lay eggs on•caterpillars, •beetle larvae, and bugs

Parasitic Nematodes

•Apply with water late afternoon when soils are >60 degrees

•Soil properties impact success

•Follow directions

Colorado Potato Beetle infected with Beauveria

B.t.– Bacillus thuringiensis naturally occurring disease effective for

caterpillar management

Apply to undersides of leaves

Most effective when pest are young

Stop feeding within a few hours, slow death

Spray in evening, breaks down in sunlight

Biorational

Inorganic

Synthetic

Environment

Pathogen

Host

Disease Triangle Prevent disease by removing a factor

Botanicals:

Soaps, Oils, Plant Extracts (Pyrethrum, Neem, nicotine, rotenone, sabadilla)

Microbial

Spinosad

When Compared to Synthetics:

Break down faster Less persistent Usually not as potent but some are more toxic Broad spectrum (kill beneficials) Used in combination rather than as sole strategy Just as much care should be used

Insecticidal Soap kills soft body pests: aphids, whitefly, mites Kills only what it contacts – not eggs Repeated applications often necessary Do less damage to beneficial predators Manages: aphids, caterpillars, leafhopper nymphs,

mealy bugs, scale crawlers, thrips, whiteflies

Horticultural Oil kills by smothering, kills all life stages (eggs must be exposed) great for scale, spider mites, mealybug Dormant Oils (dormant season application) Superior Oils (summer use oils) can damage plants at high temperatures

Pyrethrum:

Extracted from African chrysanthemumsContact poison, quick knock downLittle residualBroad Spectrum – highly toxic to beesManages: aphids, beetles, caterpillars, thrips, true

bugs

Neem (azadriachtin)

Extracted from tree grown in Africa & IndiaHormone mimicRepellantStomach poison and fungicidal propertiesRelatively non-toxic – little impact on adult beneficialsManages: Mexican bean beetle, squash bugs, aphids

Spinosad, developed from soil dwelling bacterium

Causes death within a few days

Effective for caterpillars, Colorado potato beetle, fire ants thrips

Most effective when ingested

Used for disease management

Copper – fungal and bacterial diseases Sulfur – fungal disease management Bordeaux Mix

copper sulfate + hydrated lime Diatomaceous Earth

Apply carefully

Leaf damage can occur

Silicon dioxide, finely milled fossilized remains of diatoms

Desiccant. Scratch insect exoskeleton or puncture gut lining

Apply to wet foliage

Manages: aphids, mites, caterpillars

Use D.E. products registered by EPA as pesticides, “Natural Grade”, not “Pool Grade”

Synthetic ChemicalsM

ade in a laboratory –

often based on natural substances

May kill by any or all of the following:

contact, ingestion inhalation

Always follow label instructions with all pesticides.

Older products:

Sevin, Orthene, Malathion

Broad spectrum, kill many different pests

Usually more dangerous

Newer products: Pyrethroids

Permethrin, bifenthrin, Cypermethrin, Cyfluthrin, Deltamethrin, Esfenvalerate, Fluvalinate, Lambda-cyhalothrin

Have much lower rates of active ingredient

Newer products

Imidacloprid (Merit) – systemic Fipronil – long lasting, fire ant management

Newer Products:

Insect Growth Regulators

Prevent molting, slow acting Most homeowner products available in fire ant baits

Methoprene, Hydroprene, Fenoxycarb

Myclobutinal (Immunox)

Chlorothalonil (Daconil)

Mancozeb

Maneb

Tebuconazole

Thiophanate-methyl

Propiconazole

Don’t use pesticides

Avoid using dusts or powders

Apply late in the date, after bees have returned to their hives

Avoid spraying flowers

Is host valuable?

Is problem properly identified?

Is problem life/ health threatening?

Is the plant prone to this problem?

Are effective, legal treatments available?

Will 1 to 2 applications suffice?

Have cultural practices been used?

Is treatment practical?

Keep plants healthy

Identify the plant, and the pest.

Study pest biology – target weakest link!

For best management use cultural, mechanical, biological and chemical methods

Only treat with pesticides after all of other methods explored - Use least toxic chemicals

Extension Publications

http://www.extension.org/search

NC Agricultural Chemical Manual

http://ipm.ncsu.edu/agchem/agchem.html

National Pesticide Information Center

http://www.npic.orst.edu/

Pesticide Environmental Stewardship

http://pesticidestewardship.org/homeowner/

Pesticide labels

http://www.cdms.net/LabelsMsds/LMDefault.aspx?t=

National Organic Program http://www.ams.usda.gov/AMSv1.0/nop