Charlotte Glen Horticulture Agent, Pender County Cooperative Extension
An integrated system Seeks balance, not eradication Natural Pesticides Beneficial Insects Plant Health Soil Preparation Intentionally managed Sanitation Resistant Varieties
Plant Health Mgmt Build healthy soils! Sanitation Plant selection Reduce stress Encouraging Beneficials Beneficial Insects Treatment Natural products
Understand the Problem!
Do your homework be familiar with common pests of your plants! Lots of great web resources and reference books available! Invest in a magnifying glass! Bring a sample to your local Extension office!
Two Main Groups Chewing Insects Piercing Sucking Insects
Symptoms: Holes in leaves! Frass Webbing
Many types! Immature stage of butterflies and moths Most feed on a narrow range of plants
Generally grubs underground, adults fly around, but not always Colorado Potato Beetles Japanese Beetles
Use needle like mouth parts to feed on plant sap in leaves, stems, flower buds and fruits Can cause distorted growth and leaf discoloration Many spread virus diseases! Tarnished Plant Bug
Honeydew producers Aphids Scale Whitefly Hundreds of aphids can fit on the back of a crape myrtle leaf Others Lace bug Spider mites Thrips True bugs not small! Black Sooty Mold can persist long after the insects are gone
Distortion due to aphids feeding on the backside of this river birch leaf Many species, most feed on a narrow range of plants May be yellow, green, brown, black, gray, red Produce lots of honeydew Aphids on milkweed Turnip Aphids
Mostly a problem of woody plants Whitefly sometimes on houseplants and vegetables mostly on Gardenia Both produce honeydew Lecanium Scale Tea Scale on Camellia Whitefly
Lacebugs very specific to azaleas, lantana, pyracantha, and sycamore Spider mites worse during dry weather Azalea Lacebug
Leaf footed bug Mostly feed on fruits and seeds Much larger than other P-S insects Stink Bug
Can affect: Leaves Fruits Stems Roots Vascular Tissue Only leaf diseases are realistically treatable Prevention is the key for all! Wilt vascular tissue Roots
Least damaging especially if treated early Host specific Often weather dependent worse in wet weather Entomosporium Leaf Spot on Indian Hawthorn Cercospora Leaf Spot on Hydrangea Septoria Leaf Spot on Tomato
Powdery Mildew Affects some annuals, perennials, vegetables, some varieties of crape myrtle Downy Mildew Basil, cucumbers, lettuce, cabbage
Fireblight Canker Root Rot Wilt Virus Nematodes Fireblight on Apple and Pear, can only prune out once infected
Problem of woody plants Usually associated with drought stress Can only prune out infected parts, well below point of infection
Associated with poor drainage! Can effect seedlings and mature plants Roots turn brown, soft and mushy Plants may die quickly or slowly Persist in the soil
Clog up vascular tissue (circulatory system) Soil born Most common in vegetables esp. tomato Fatal Southern Bacterial Wilt in Tomato
Spread by insects (piercing sucking) and pruning tools Not usually deadly, often cause strange patterns or color breaks on leaves and flowers Tomato Spotted Wilt Virus an exception, fatal, spread by thrips
Affect many vegetables, figs, peaches, gardenias Live in the soil, microscopic worms Plants stunted, low yields
Blossom End Rot Calcium deficiency most often due to fluctuating water levels Low ph can also cause Heat and drought cause leaves, flowers, and fruits to drop B.E.R. affects tomatoes, peppers, squash and melons
Build healthy soils! Sanitation Plant selection Reduce stress Beneficial Insects
Good Offense 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 Drought stressed plants glow and scream to insects
Build Healthy Soils Healthy soils support beneficial microbes! Soil test Manage nutrients & ph Add organic matter Alleviate soil compaction
Plant vegetables and fruits in sunny areas with well drained soil Choose ornamentals suited to site conditions Shade or sun Sand or clay High or low ph Salt spray
Variety Selection Choose resistant cultivars when possible research possible diseases and resistant varieties Purchase disease- & insect free - plants from reputable sources Select plants that will be able to grow to their full mature size in the allotted space. Planting resistant varieties is the ONLY way to manage tomato spotted wilt virus and nematodes. Most heirloom varieties have little to no resistance to these diseases.
Crop Rotation Avoid planting crops in the same family in the same location multiple years.
Planting Dates Avoid 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
Interplanting Avoid 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
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 pests Proper spacing depends on mature size of plant most plants do best when leaves just touch at full size
To reduce leaf diseases, avoid wetting leaves Most fungal leaf diseases require 4 hrs + of continual leaf wetness to infect Don t overwater root rot! Drip irrigation delivers water through pipes directly to the soil Water fan sprinklers spray water in the air, wetting foliage
Too much or too little nutrients makes plants more susceptible to problems Compost usually does not supply all the nutrients plants need Soil test to find out what nutrients are needed Organic fertilizers are readily available and naturally slow release
Weed Control 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
Exclusion Mechanical barriers such as collars, row cover, netting, sticky barriers and fencing can be very effective against specific pests. A cardboard or foil collar can protect young vegetables from cutworms Floating row covers can keep flying adult insects from laying eggs on vegetables e.g. Cabbage whites
Traps Most insect traps are most useful for detection and monitoring There are many kinds must get right type for pest Be sure that you are not attracting more pests into an area! Pheromone traps have chemicals that mimic mating hormones
Handpicking Inspect plants for egg clusters, beetles, caterpillars, or other pests. Squash or drop them in sudsy water. Handpick bagworm bags in winter removes eggs
Control 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
Sanitation If only a few leaves are infected, remove them from the plant Pull out infested plants Remove infected leaves Clean up mummy fruit! Mummy berry survives in shriveled fruit that fall to the ground
Kills weed seed, diseases and insects in soil surface (3-4 ) Till beds, water, and cover with clear plastic for 6-8 weeks in July-August Disturb soil as little possible afterward to avoid bring untreated soil up to the surface.
Small flowers Dill, Fennel, Basil Yarrow, Sedum Goldenrod, Joe Pye Weed Daisy flowers Purple Coneflower, Cosmos Others Salvias, Mints, Asclepias, Zinnia Goldenrod Purple Coneflower
Hover Fly adults look like bees or wasps 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. Hover fly larvae look like small slugs or caterpillars voracious aphid eaters
Lacewing Eggs Juvenile Aphid Lion Adult
Parasitic Wasps
Assassin Bug
Made from natural products Minerals Plant derived Microbial Still need to read and follow all label directions!
Is the problem serious? Will depend on the plant! Is the problem likely to reoccur? Is the problem correctly identified?? Azalea leaf gall is completely harmless also by the time the galls form it is too late to treat.
Active ingredients listed on the label OMRI listed approved for use by certified organic farmers Some products have natural active ingredients but are not OMRI approved Active ingredients are listed on the label
Not persistent Break down quickly, sometimes in a day Most are much safer to beneficials! No residual activity or systemic uptake Must reapply often Insecticides kill by contact or ingestion Thorough coverage essential Pest must be present Treat once insect pests are present re-treatment often necessay
Not as potent as synthetic pesticides Must be part of integrated system! Most effective when problem just starting! Monitor regularly, catch early Must know the pest to choose a treatment! Correct identification essential! Many products very specific only work on a few pests Pine Sawfly larvae look like caterpillars but are not B.t. will not control them.
Insecticidal Soap kills soft body pests: aphids, whitefly, mites Kills only what it contacts not eggs Repeated applications often necessary Horticultural Oil kills by smothering, kills all life stages (eggs must be exposed) great for scale, spider mites, aphids, whitefly Can damage plants at high temperatures No residual activity for either!
B.t. Bacillus thuringiensis naturally occurring disease effective for caterpillar control Most effective when pest are young Stop feeding within a few hours, slow death Spray in evening, breaks down in sunlight Separate strain for Colorado potato beetle control
Derived from Neem tree seed oil Over 70 cmpds, Azadirachtin believed most active Controls aphids, mites, thrips, whitefly May help control powdery mildew Primarily acts as growth regulator works best on young insects Breaks down in sunlight
Developed from soil dwelling bacterium Causes death within a few days A little more persistent than B.t. and neem (3-5 days) Effective for Caterpillars, Colorado potato beetle, Fire ants (baits)
Protect plants from disease as part of integrated system Do not cure problems once they have started Ideally apply before disease begins! Neem and oils may have some effect on diseases, particularly powdery mildew Early Blight on Tomato Too late to treat!
Sulfur fungal disease control Lime-Sulfur dormant season only Copper fungal and bacterial diseases Bordeaux Mix copper sulfate + hydrated lime Contact protectant Apply carefully - Leaf damage can occur
Bacillus subtilis For leaf diseases Potassium bicarbonate Especially effective for powdery mildew Sold as Remedy and other brands Must apply at first symptoms or before! Serenade is one brand name of B. subtilis
Organic pest management is an integrated system Focus is on pest prevention Building healthy soils, plant selection, and good sanitation are key Natural products work as part of the system Must know pest id before choosing a product Some problems cannot be controlled!
Pender County Cooperative Extension 801 S. Walker St., Burgaw 259-1235 http://pender.ces.ncsu.edu Thanks to Lucy Bradley, Steve Bambara, and Debbie Roos for content & images