Spring and summer just wouldn’t be the same without hordes of crawling, marching, burrowing, chewing, dive-bombing insects. Literally. Summer would be vastly different, void of many flowers, fruits and birdsong without our insect frenemies. Insects are pollinators, natural control for even more damaging insects, a food source for birds and small mammals. Insects are helpers. Just before they help themselves to your tomatoes and move into your attic.
But don’t touch the trigger on that can of Raid. Indiscriminate pesticides can be so easy and will kill the beneficial insects right along with the pests. With chemicals, even boosters like Miracle Grow, it takes a long time for your garden to invite the good insects back in. Meanwhile, pests may develop resistance, soil life is negatively slowed, and you’ve got one more aerosol container to put in the landfill.
How then do we protect our favorite plants so uninvited freeloaders don’t see the garden as their personal salad bar?
Use a combination of methods:
- Home gardeners and landscape professionals save time and money with integrated pest management. IPM fosters healthy environments that resist most pests. Ask the staff of for further advice.
- If it’s too late to select the right plant for the job, favorable drainage and irrigation might be the solution.
- Lightly till soil to interrupt egg cycles.
- Introduce natural controls like lady bugs, lace wings and parasitic wasps.
- When pests invade and a jet of water doesn’t work, less toxic materials, like Safer Soap, may work.
In other words, it all depends. Want to troubleshoot your pest woes? Visit The University of California, Agriculture and Natural Resources Department’s comprehensive, public-friendly website at www.ipm.ucdavis.edu.
Below, Patch made a list of common pests now playing in a garden near you. We culled solutions from UC IPM online and from UC ANR’s excellent Pests of Landscape Trees and Shrubs, An Integrated Pest Management Guide, Second Edition, published by UC ANR Communication Services, Oakland, California.
Pest ID 101:
Cultivation practices make a difference. Insects need leaves like soup kitchens need ladles. So before it gets really hot, and nobody wants soup anyway, say, March through June, take special care to avoid hyper-rapid plant growth. Too much nitrogen fertilizer will generate speedy but weaker leaves and stems. Eliminate the pest magnet. Pruning also stimulates new growth, so keep an eye peeled after clipping.
You may be days away from a strong blast of water on psyllids, tiny, cricket-like buggers that suck plant juices from leaves. Psyllids cause leaf curl, defoliation, and transmit bacteria into the vascular system of plants through leaf chewing. They feed on California peppers, lemonade berry and sugarbush, among other plants.
The non-native Asian Citrus Psyllid is a real threat to the citrus industry, already damaging Florida production. According to the California Department of Food and Agriculture website, Los Angeles County Ventura, San Diego, Riverside and much of Orange County, are under quarantine. The LA Times reported the Asian Citrus Psyllid was found in October, 2010, in Montclair and Upland, and in December, 2010 in Ventura. ABC Local News reported in April of 2011an infected psyllid was found in Camarillo. If you see a 3 to 4 mm grayish-tan bodied, jumping or flying insect with mottled brown wings on any citrus tree, contact the California Department of Food and Agriculture. At present biological predators are being reviewed.
Whitefly. Not true flies but related to psyllids and aphids. They drink the carbs from plants and secrete honeydew that attracts a fungus which, in turn, produces black sooty mold. Ants, holding imaginary “Will Work For Honeydew” signs, enslave whitefly colonies for the sweet, sweet syrup. Whiteflies lay eggs on the underside of leaves. Hatched nymphs crawl off, attach themselves to tender plant parts, sucking until adulthood. Coincidentally, this was the B story in Elia Kazan’s controversial film Babydoll. In the summer, whiteflies can produce several generations.
Giant Whitefly. The white, waxy “beards” hanging from various plants is the deposit of this Mexican marauder. Honeydew producers, Giant Whitefly is also responsible for black sooty mold on hibiscus, citrus and avocado trees. Treatment: remove leaves, spray with water, and don’t plant red hibiscus, giant bird of paradise or Xylosma, favorite host plants.
Aphids are tiny, soft-bodied, flying insects that suck plant juices. Over 200 California resident species may be black, green, yellow or white. And efficient? You bet. They don’t waste time mating but reproduce asexually, giving birth to live, chewing nymphs. Every two weeks in the summer. Not my idea of a vacation.
Woolly Aphids are found on apples, cotoneaster, elm, hawthorn and pyracantha leaves and bark. They over-winter in bark crevices, so prune out damaged and dead wood. The next generation migrates to leaf buds, causing new leaf growth to curl and deform. Spray these fuzzy white blobs off branches with strong water streams or smash between fingers. Aphids thrive where ants are tending them. So get rid of the ants. Search citrus trees for armies running up and down trunks to discover aphid colonies.
Ants. Over 200 ant species exist in California. Most are beneficial but there are about 12 varieties that give the good ants a very bad reputation. The good ones aerate soil, prey on insect pests, decompose decaying yard debris. The bad ones weaken tree limbs (carpenter ants), chew tender bark (pavement ants), and sting people (fire ants). Some harbor honey slaves and raid your home for water.
Pavement ants nest in foundations, under sidewalks, in lawns. They like protected temperatures and access to water. Reduce their numbers through improved soil drainage, repairing leaky sprinkler heads. In spring, caulk access points into the house, or seal with petroleum jelly. Vacuum ant trails and wipe with soapy water. Use baits, or bait stations. These are slow-acting but effective, especially when begun in early spring to control against summer population explosions.
Red Imported Fire Ant (RIFA). According to the LA County Agricultural Commissioner/Weights and Measures Web site, Red Imported Fire Ants are aggressive and build 18” or higher gopher-like mounds. They come in varying lengths, from 1/8” to ¼”. They aggressively attack invaders, stinging repeatedly, injecting venom each time. If you or your pets have an allergic reaction such as dizziness, nausea, constricted breathing, headache or sweating, seek medical help immediately. RIFA have infested cities in South Los Angeles County and Santa Clarita to the northwest.
When purchasing landscape materials, ask your nursery or grower if their plants are certified RIFA-free. Commercial shipments of soil, sod, plants with roots growing into the ground and used soil-moving equipment must be inspected free of charge prior to moving, per the Cooperative Red Imported Fire Ant Project of Orange County. For further commercial information call 562-795‐1100. To report a citizen sighting of Red Imported Fire Ants, call 1-888-FIREANT toll free.
If a job is too big or time too short, pest control professionals may be the way to go. Trained and certified to properly use strong chemical treatments, they will follow up with recommended treatments to keep the invaders to a minimum.