Get the upper hand on Ants in your garden.

by Rincon-Vitova Insectary

Ants 

There are more than 12,400 species of ants throughout the world. In California, there are about 270 species, but fewer than a dozen are important pests. Ants interfere with biological control.  Honeydew-secreting pests, like aphids, supply sweet food to the ants. In turn, ants protect the pests from beneficial insects that try to eat them. Controlling ants is important when attempting to control these honeydew producing pests. Baiting is a low risk approach that interrupts ants’ interference. Once they have found an adequate food source, they create a pheromone trail, a chemically marked highway, to and from the ant nest. More bait stations are not necessarily the answer, but strategic placement is important. 

Identification 

Ants are close relatives of bees and wasps.  

Common wingless adult forms, known as workers.  

Winged forms, which leave the nest in large numbers in warm weather to mate and establish new colonies, are often mistaken for winged termites. 

Life Cycle 

A newly mated queen typically establishes a new colony.  

After weeks or months of confinement underground, she lays her first eggs.  

When the eggs hatch, she feeds the white, legless larvae with her own metabolized wing muscles and fat bodies.  

Several weeks after the larvae pupate; sterile female adult workers emerge and dig out of the nest to collect food.  

The queen continues to lay eggs. As colony numbers increase workers add new chambers and galleries to the nest.  

After a few years, the colony begins to produce winged male and female ants, which leave to mate and form new colonies. 

*Argentine ants differ – nests are shallow, extending just below the soil surface (dry conditions will nest deeper) 

Colonies aren’t separate but linked to form one large “super colony” with multiple queens.  

Newly mated queens dispersing to found new colonies are accompanied by workers 

Monitoring 

Regularly inspecting is an important part of an IPM program.  

Check near attractive food sources or moist areas and along pipes and electrical wires. 

Look for large trails of ants or for just a few stragglers. Stragglers are scouts randomly searching for food/ nesting sites. Try to follow trails to where ants are entering the building, and also to the nest if possible.  

Look indoors and outdoors for holes or cracks in foundations and walls that provide entry points to buildings. 

Cultural Practices 

It is unrealistic and impractical to attempt to totally eliminate ants from an outdoor area.  

Focus efforts on excluding ants from buildings or valuable plants and eliminating their food and water sources.  

In pots: Submerge pots (20+ minutes) in a solution of insecticidal soap and water: 1-2 tablespoons soap per quart of water.  

Submerge so the surface of the soil is just covered by the water-soap solution. 

Ants can be kept out of plants by banding trunks with pest glue such as Tanglefoot.  

Trim branches to keep them from touching structures or other plants so ants are forced to climb up the sticky trunk. 

Protect trunks by wrapping with heavy paper, duct tape, or fabric tree wrap and coating this with the sticky material.  

Check coating every 1-2 weeks for debris and dead ants, which will allow subsequent ants to cross. 

Mechanical Disruption and Exclusion: destroy ant mounds as much as possible with a shovel or pick. 

Auntie Fuego soil conditioner (orange oil, humic acid, molasses) also deters ants. 

Granular Ant Bait 

Dry granular ant baits are a discrete way of treating public access areas and may be used with liquid systems 

In low rainfall areas, be mindful of buildup of boron in the soil to avoid burning plants. 

Boric Acid Ant Bait Systems 

Boric Acid (borate or various forms of sodium borate) is a salt that is a low risk insecticide. It is considered non-toxic. 

Boris acid is less toxic to humans than table salt.  

In trace amounts, the boron in boric acid is a plant nutrient; high concentrations will cause a little salt burn in plants.  

Foraging ants take low concentration bait solution back to colony in repeated trips.  

The colony will weaken and possibly die. This may take 1 – 2 months.  

Higher concentrations of boric acid kill the ants before they can take the food back to the colony.  

The 0.5 – 1% concentration is more effective long term at reducing the colony. 

DIY: Use any container with 1/8 inch holes so ants can get in but bees and butterflies can’t. Put in twigs, or plastic “bridge” material so ants can access bait without drowning. 

Recipe: 1C Sugar / 2C Water / 2 teaspoons boric acid [1% boric acid in 25% syrup (by weight) developed by UC] 

Not interested in sweet bait? Try cups with a small amount of corn meal wet with vegetable oil, or peanut butter. 

For oily baits, try 10% boric acid by weight (or less if ants reject the bait/dead individuals are seen near bait). 

If ants are more attracted to any of these foods, change the bait in the bait stations to more attractive matieral.  

Placing of Liquid Dispensers 

For initial baiting try 2 – 8 liquid bait stations around a home or 4 – 16 per acre in a production setting.   

Structural baiting:  

-Always bait outside of residences  

-At least one station on each side of structure, (depending on size and number of different structure walls).  

-Key areas: by common corner where insects converge from more than one direction 

-Place by the A/C condenser water overflow outlet.  

-Water is always a primary attractant.  

-North-side: high shade & moist areas.  

-Do not put stations directly over nests 

-Do not use insecticides near nests   

Lawn, garden & rest of property:  

-For full property protection, place additional ant bait stations spaced around perimeter of lot.  

-Avoid locations where substantial water run-off will occur.  

-Placement Guideline around property:  

– Up to two acre lot size, use a min.    of 4 units  

– Greater than two acres, use 2 units for each added acre 

– Adjust as needed based on activity.  

Agricultural Acreage:  

-General: use 14 per acre or about 50 to 60 foot apart in a matrix. 

-Number of ant bait stations per acre depends on the targeted species (Argentine Ant, White-footed Ant, etc.); the degree of infestation; and the acreage involved and whether it is contiguous acreage.   

-If trying to manage Argentine ants, move stations to perimeter after no more activity is observed in interior of the block or property.  

-Argentine ants may forage as far as 75 to 200 feet. 

Check bait stations every few days for the first week of baiting. Refill bait stations as needed. 

If no bait is taken from bait station and no ants are seen around it, move the station to another location.  

Certified organic farms: bait cannot contact the soil. Use secure bait stations or place station on a tray to contain spills.  

Tips to Improve bait effectiveness 


Remove any particles of food, residues of sweet liquids, or other attractive material from ant-infested areas.  

Treatments in late winter and early spring when ant populations are just beginning to grow will be most effective.  

Ant preferences can change throughout the year; set out different formulations of various bait, giving ants a choice.  

Baits can dry up or become rancid and unattractive over time. 

If dead ants are seen inside bait stations, wash with plain water, refill and replace. 

Avoid using pesticides: Phenylpyrazoles (fipronil), Avermectin B (abamectin). hydramethylnon, 

Pyrethroids: (bifenthrin, cyfluthrin, fluvalinate, and permethrin) actually contact insecticides that rapidly kill foragers and don’t control the colony.  Carbamates (propoxur) or Oxadiazines (indoxacarb) aren’t very effective, because the active ingredient is too fast-acting. These materials are highly toxic to natural enemies and pollinators. 

Safer contact insecticide hard surfaces: Mix 4- 6 ounces orange oil per gallon with 2- 4 ounces liquid detergent or soap. Treat for ants around trees: Saturate soil around trunk, and look for where ants are coming from.  

Orange Guard is a ready-to-use orange oil spray. 

Fighting off the Leafhopper in your garden.

by Rincon-Vitovo Insectary

Leafhoppers 

Leafhoppers feed on leaves and stems with piercing sucking mouthparts that extract a bit of fluid from the plant. Most have insignificant effects. A few species cause small, light flecking/stippling injury may occur at the feeding site. Black sooty mold is a secondary outbreak from their honeydew. Although some leafhoppers transmit plant pathogens that cause diseases of crops none of these leafhopper-vectored plant diseases are presently known to affect hemp.  

Identification 

Leafhopper adults are slender, wedge-shaped, and less than or about equal to 1/4-inch long.  They have varying colors; some species are brightly colored, while others blend with their host plant.  Leafhoppers are quite active; they crawl rapidly sideways or readily jump when disturbed.  Sometimes leafhoppers can be confused with aphids or lygus bugs: Lygus can be identified by their red-tipped antennae.  Aphids can be distinguished by two “tailpipe” structures (cornicles) protruding from their hind end.  1 or more long rows of spines on the hind legs distinguish leafhoppers from most other insects they may resemble. 

Life Cycle 

Females insert tiny eggs in tender plant tissue, causing pimple-like injuries.  Leafhoppers overwinter as eggs on twigs or as adults in protected places such as bark crevices.  In cold-winter climates, leafhoppers may die during winter and in spring migrate back in from warmer regions.  Egg to adult is approximately 3 weeks. Several overlapping generations may occur during the growing season. 

Monitoring 

Leafhoppers are often more present in dry weather, looking for moisture from plants.  Look for adults, nymphs, and their pale cast skins on the underside of leaves.  Black spots of excrement and cast skins may be present on leaves and/or fruit.  Damage shows as pale or brown stippling. Shoots may curl and die. Some leafhoppers cause diamond-shape yellowing from the leaf tip.  A few species secrete honeydew, which often leads to black sooty mold growth.  If honeydew/sooty mold is present, be diligent watching for ants. 

Cultural Practices 

Low risk materials applied to infested foliage reduces numbers of nymphs – thorough coverage of undersides is critical. Insecticidal soap: fatty acid salts weaken the cuticle (exoskeleton), and won’t leave a harmful residue.  To help the soap penetrate the insects’ outer shell, mix 1 Tbs of isopropyl alcohol to 1 Qt of the spray.  Dust with Diatomaceous Earth: these jagged particles cut the insects and expose to desiccation & disease. It will need to be reapplied as it gets wet.  Narrow-range oils: smother pests by coating their spiracles (breathing holes)  

Bordeaux mixture (copper sulfate & slaked lime = fungicide) can repel adults and act as antifeedant. 

Neem oil – not for flowering plants (will leave smell/taste on buds) Neem Oil (Azadirachtin): mimics IGRs: primarily kills immature insects (they fail to complete molts). It also acts as an antifeedant & repellant. Neem is less effective on aphids & some grasshoppers. Neem also breaks down in water – don’t mix more than needed. It persists 4-8 days as foliar spray, and weeks if drenched. Neem does not harm foraging bees. 

Habitat enhancement: strip of alfalfa, corn, pea provide nutrition  

Avoid using pesticides: Neonicotinoids (imidacloprid), Organophosphates (acephate), Carbamates, (carbaryl). These materials are highly toxic to natural enemies and pollinators. 

Bio-Control 

Beauveria bassiana (for aphids, thrips, WF) 

68-86 °F >92% RH 

An entomopathogenic fungus wide host range, including soft-bodied beneficials 

Best for sap-sucking & chewing insects 

Spores germinte on insects – kill in 2-10 days 

Some strains have 3-7 day residual activity 

Weekly applications can prevent insect population explosions  

Application Rates: Application Rates may vary among different commercial products. Read labels carefully. 

½ to 2 qt per 100 gallons for liquid emulsion suspension products 

½ to 2 lbs per 100 gallons for wettable powder products 

Weekly applications can prevent insect population explosions  

Metarhizium anisopliae  

Fungal pathogen penetrates skin, enters spiracles 

Infected insects stop feeding and die in 4-10 days 

Works best against sap-sucking insects, like whiteflies and aphids (other strains for thrips, beetles) 

Best in high humidity and moderate temps: 75-82°F 

Application Rates: Application Rates may vary among different commercial products. Read labels carefully. 

40-80 oz per 100 gallons of water as a drench 

8–64 oz per 1 acre as a foliar spray 

Generalist Predators:  

Hippodamia convergens  

Ladybugs – will feed on eggs and immature stages both as adults and larvae.  

Often leave after released 

Application Rates: 1 beetle per sq ft.  

Reapply if necessary 

Chrysoperla rufilabris 

Green Lacewing – generalist 

Wingless predator for 2-3 weeks 

Will focus on eggs and immature stages, but can catch adults 

Application Rates: 1,000 eggs per 2,500 sq ft or 5,000-10,000 per acre 

Eggs on Cards: hang 1-2 units/bush, 1-5 units tree 

Pre-hatched Larvae: 20/bush, 100/tree 

Reapply every two weeks to suppress populations, monthly for maintenance 

Summary of Strategies 

Dust with DE/kaolin clay preventively 

Plant habitat to attract native beneficials (Like Orius) 

Ant Control 

Low risk “soft pesticides:” Insecticidal soap, Neem/Hort oil 

Beauveria bassiana 

Metarhizium 

Augment with beneficials: Green lacewing and Ladybugs 

Controlling Grasshoppers in our gardens

by Rincon-Vitova Insectary

Grasshoppers

Most grasshoppers are general feeders, but they prefer young green plants and some annual flowers. Chewing mouthparts make large, round, smooth holes in leaves. Heavy infestations can strip plants to stalks. During major outbreaks they feed on almost any green plant, and damage may occur over a considerably longer period.

Identification

Hind legs, have greatly enlarged femurs, are well adapted for jumping. 

Antennae are relatively short versus crickets and katydids, which have long antennae. 

Most are winged and are good fliers, although a few species are flightless.

Life Cycle

In late summer and in fall, adult females deposit eggs in soil in undisturbed areas: grassy foothills, ditch banks, etc. 

Eggs hatch in spring, and young nymphs begin to feed on nearby plants. 

Usually grasshoppers have only one generation a year. Adults can live two to three months.

Adults die out when food becomes scarce or when weather becomes too cold. 

Monitoring Excerpt from Manitoba Hemp: 

The probability of grasshopper pests is higher when production occurs near pasture or hay land. 

Grasshoppers can move into the field in the spring if conditions are favorable for an early hatch. 

Late season infestations can result in damaged seed heads and possibly reduced production.  

Economic thresholds are unknown at this time.

Cultural Practices

When numbers are low, they can be handpicked and squashed. 

Cones, screened boxes, floating row covers, and other covers provide some protection (Grasshoppers can eat through cloth or plastic row covers, try using metal window screening). 

Chickens and guinea hens are excellent predators but can cause damage to some plants.

Set up bird houses, baths, and feeders, to attract predators. 

Use companion plants to repel grasshoppers: cilantro, calendula (pot marigold), sweet clover, and horehound 

Keep a trap border of tall grass or lush green plants around the perimeter of the garden to divert insects 

Don’t mow this trap crop or let it dry out, or the grasshoppers will go straight into the garden

Use jar traps: sink glass jars into soil and fill half way with molasses mixture: 1 part molasses to 10 parts water.

Dust the leaves with thin layer of all purpose flour, which can cause starvation by gumming up their mouths.

Dust with Diatomaceous Earth: these jagged particles cut the insects and expose to desiccation & disease. It will need to be reapplied as it gets wet.

Neem oil – not for flowering plants (will leave smell/taste on buds)

Neem Oil (Azadirachtin): mimics IGRs: primarily kills immature insects (they fail to complete molts). It also acts as an antifeedant & repellant. Neem is less effective on aphids & some grasshoppers. Neem also breaks down in water – don’t mix more than needed. It persists 4-8 days as foliar spray, and weeks if drenched. Neem does not harm foraging bees.

Garlic Barrier spray: excellent repellent. Mix 2 oz Garlic Barrier, 1 Qt Fish Emulsion, and 5 Gal Water. Spray. 

Homemade garlic spray, blend two bulbs of garlic with 10 cups of water and heat up the mixture until it starts to boil. Let the mixture sit overnight. To use, fill a spray bottle with one part garlic solution and three parts water.

Garlic Spray: garlic odor diminishes in about 30 minutes as the plants absorb it. Garlic Barrier travels through the plant systemically, protecting roots, stems, leaves, flowers and fruit. 

Does not change the taste or smell for human, insects can’t stand the natural sulfurs absorbed from the garlic

Grasshoppers

Avoid using pesticides: Carbamates (carbaryl), Pyrethroids (bifenthrin, cyfluthrin, fluvalinate, and permethrin). These materials are highly toxic to natural enemies and pollinators.

Bio-Control

Nosema locustae baits containing the protozoan kill nymphs of migrating grasshopper nymphs early in the season. 

Nosema baits are slow-acting and not intended for stopping sudden outbreaks.

Application Rates: Application Rates may vary among different commercial products. Read labels carefully.

25 bran flakes per sq ft

Beauveria bassiana (for aphids, thrips, WF)

68-86 °F    >92% RH

An entomopathogenic fungus wide host range, including soft-bodied beneficials

Best for sap-sucking & chewing insects

Spores germinte on insects – kill in 2-10 days

Some strains have 3-7 day residual activity

Weekly applications can prevent insect population explosions 

Application Rates: Application Rates may vary among different commercial products. Read labels carefully.

½ to 2 qt per 100 gallons for liquid emulsion suspension products

½ to 2 lbs per 100 gallons for wettable powder products

Weekly applications can prevent insect population explosions 

Summary of Strategies

Hand picking

Row Covers

Trap grasses 

Companion plants to repel

Garlic Sprays to repel 

Flour dusting

Molasses bait traps

Nosema bait early

Beauveria bassiana early