Posts Tagged: integrated pest management
Spotting ants in the home or yard is no reason to reach for insecticide sprays or call an exterminator. UC Cooperative Extension experts say the insects can be managed by residents in ways that are effective, inexpensive, safe and environmentally kind.
“Ants are probably the No. 1 most common pests of our homes and gardens,” said Carolyn Kinnon, an environmental horticulturist and instructional associate at Mira Costa Community College. “Scientists find chemicals in our waterways that include pesticides commonly used to kill ants.”
Kinnon teamed up with UCCE community education specialist Scott Parker to present a Healthy Garden-Healthy Home online ant workshop during the COVID-19 pandemic to take the place of a planned in-person event. Healthy Garden-Healthy Home was initiated in 2005 with a grant from the California State Water Resources Control Board and continues with funding from San Diego County. With the move online, the workshop attracted four times more participants that usual.
“A silver lining of the COVID disaster has been our ability to reach out to many more individuals,” Parker said.
Healthy Gardens-Healthy Homes aims to cut residents' use of chemicals and reduce soil erosion that can wash into gutters with irrigation or rain water, course through storm drains and into streams, reservoirs and the Pacific Ocean. During the recent UCCE webinar on healthy ant control, Kinnon introduced science-based solutions that can be combined to keep ants at bay.
Use ant biology to battle ants
Ants are always looking for food and will forage any accessible source. Short circuiting this biological need is the first approach to controlling the pest. Outside, ants are often attracted to a sticky, sweet honeydew that pests like aphids leave behind when they feed on plants. Washing off aphids and honeydew with a sharp stream of water from the hose reduces the food source.
In spring, Kinnon said, ants like to feed on proteins, like seeds, nuts, dog food and other fatty substances. Fallen nuts, bird seed and leftover pet food should be discarded to reduce ant activity.
“When honeydew production from sap-sucking insects declines in the hot summer, and there is an absence of food sources outdoors, ants may come indoors,” she said. “Ants will travel several hundred feet in search for food.”
Removing inside food sources – like spills on counters and floors – and blocking access – by filling in holes and cracks – is the first defense against an indoor ant invasion. Kinnon recommends keeping food containers clean and sealed, rinsing empty recyclables – particularly sugar-sweetened beverages – and wiping up grease on barbecues and stove tops.
Wipe up ants and their chemical trails with an all-purpose cleaner, and fill tiny gaps, cracks and holes with caulk to make their entry difficult.
Another way to achieve environmentally friendly ant management is coming to terms with the fact that they can't be eliminated from outdoor areas.
“Our goal is to focus on reducing population numbers,” Kinnon said. “We have to tolerate a certain number.”
Spraying a pesticide on an ant trail or sprinkling granular pesticides will only kill a fraction of the ants in the yard. Those materials can run off and pollute watersheds.
If cleaning up food sources, exclusionary measures and increased tolerance aren't enough, pesticide baits are an additional integrated pest management tool.
“This works because female worker ants take the bait back to the nest and feed it to other ants in the colony,” Kinnon said.
The bait must be slow acting so it doesn't kill the worker before she gets back to the colony. Kinnon recommended baits with no more than .5% active ingredient. For best bait placement, follow trails to find the nest and place the bait close by in a safe bait station. If the nest can't be found, the bait station can be placed along the trail.
Central Valley residents from Visalia to Sacramento look forward every year to the beginning of strawberry season in early April, when roadside strawberry stands operated by Hmong and Mien farmers open to the public.
These farms grow strawberry varieties such as Chandler and Camarosa that haven't traded flavor for shelf life – they don't ship or store well, but they are far sweeter than varieties usually sold in stores, and they reach their peak ripeness and flavor in the fields next to the strawberry stands.
As strawberry season opens this year, farmers are hoping that customers will still stop by the stands to pick up their fresh, seasonal strawberries, and also that they will observe 6-foot social distancing and other guidelines to reduce the spread of COVID-19. UC Cooperative Extension agricultural assistant Michael Yang and I were interviewed on a local news station to encourage Fresno residents to practice these guidelines while supporting local farmers.
To assist Fresno strawberry farmers, the UCCE small farms team in Fresno County developed, printed, and distributed signs for roadside strawberry stands reminding customers to observe social distancing and other safety practices, as well as guidelines for farm stands to reduce the spread of COVID-19. Versions of the signs were also developed for strawberry stands in Merced and Sacramento, as well as a general sign for local produce at any farm stand.
Signs and safety guidelines were printed with funding from the Western Extension Risk Management Education Center, and Michael Yang distributed large printed versions of the signs to all strawberry stands on the Fresno County Fruit Trail map in Fresno County. These materials have also been shared with UCCE small farms and food systems advisors as well as nonprofit and agency partners and county Agricultural Commissioner's offices, and they are available for printing on the UCCE Fresno strawberry website.
Even as Californians shelter in place to contain the novel coronavirus that causes COVID-19, nutritious food remains vital to the health and well-being of our communities.
“Eating fruits and vegetables is known to benefit our overall health and help our immune system,” said Lorrene Ritchie, director of the UC Nutrition Policy Institute. “At a time when we need to be especially vigilant about staying healthy, eating healthy is essential.”
Farms, farm stands and farmers markets are listed as “essential businesses” in the state shelter-in-place order because they are important parts of the food supply. Urban farms are included in this category. As large produce distributors struggle to switch from selling large quantities to restaurants, schools and institutions to supplying supermarkets, these small businesses may offer a better selection of fresh foods, and may be closer to homes and less crowded.
To help minimize exposure and risk of spreading of the virus, urban farms need to follow some key guidelines from the CDC , said Jennifer Sowerwine, UC Cooperative Extension metropolitan agriculture and food systems specialist in the Department of Environment, Science, Policy and Management at UC Berkeley.
UC Cooperative Extension has compiled a list of resources for farmers, community gardeners and other people working in the food system to ensure that they can continue supplying fresh, healthy and affordable food to Californians.
“Social distancing, heightened health and hygiene practices and cleaning and disinfecting reduce the risk,” said Sowerwine.
Although eating a nutritious diet can boost our immunity, the Los Angeles Times reported produce sales plummeted by 90% or more at Southern California produce markets after the statewide shelter-in-place rules went into effect.
“It's worrisome to see that sales of fruits and vegetables are dropping so sharply, but not surprising,” said Rachel Surls, UC Cooperative Extension sustainable food systems advisor for Los Angeles County. “As people shop during the crisis, they may be prioritizing groceries that can be stored for a longer time in the fridge or pantry. And they may be on a very limited food budget, even more so than usual, so they are likely prioritizing essentials like bread and rice and baby formula.”
To support farmers in California, the UC Sustainable Agriculture Research and Education Program created a directory at http://www.calagtour.org for consumers to find local farms to purchase produce directly.
For families who have lost jobs and income, the risk of food insecurity increases. Some families could supplement their food from gardens and urban agriculture during this crisis.
Consumers must practice safety, too, when visiting farmers markets and farm stands. UC Cooperative Extension small farm advisor Ruth Dahlquist-Willard explained, "Things like keeping the minimum six-foot distance from customers, not touching any produce that you're not planning to buy, leaving as soon as you've made a purchase and washing the produce when you get home would be some good guidelines."
The virus is thought to be spread mainly from person to person, however there is evidence that COVID-19 can last for days on hard surfaces, thus the need to ramp up good health and hygiene practices, social distancing and cleaning and sanitizing of surfaces.
University of California research and extension faculty have compiled a list of helpful fact sheets and resources for farmers, community gardeners and other food system workers to ensure fresh, healthy and affordable food for communities across the state:
- Food-related resources for consumers and members of the food industry for COVID-19
- on the UC Davis Food Safety website.
- Sowerwine's PowerPoint presentation Safe Handling Practices for Fresh Produce in a Time of Coronavirus Disease 2019 (COVID-19) for urban farmers.
- A set of policies and procedures for safe food handling at the farm during COVID-19 provides step-by-step instructions for applying new food and health precautions on the farm including checklists, standard operating procedures and signage posting guidelines for preventing the spread of infection.
- COVID-19 safety guidelines for farm stands.
- Handouts for safe food-handling at home that can be distributed to customers receiving food from the farm.
All of these resources are posted on the UC Urban Agriculture website at https://ucanr.edu/sites/UrbanAg.
“During this challenging time, I am heartened by the quick and thoughtful responses by many extension, grassroots and institutional efforts, including Community Alliance with Family Farm's COVID-19 Responses and Resources for California Family Farms, Mutual Aid organizations where groups of young, healthy and lower-risk people are bringing food and services to vulnerable people who shouldn't be in public at all, and Bayareafood.info that seeks to support local restaurants, farmers, and food systems workers as they weather this latest storm,” said Sowerwine. “Crisis can spawn innovation, and I am hopeful that through this, we will come out the other end with a more compassionate and resilient food system.”
To control spider mites, many almond farmers have taken to routinely spraying their trees with a miticide in May. However, research by UC Integrated Pest Management advisor Kris Tollerup shows that the pesticide application could cause more harm than good.
“The preventative sprays do suppress spider mite populations, but there's no beneficial effect because the mites show up very late in the season and the population density remains well below an economic level,” Tollerup said. “A natural enemy, six-spotted thrips, will likely show up and suppress the mite population before any damage occurs.”
Tollerup recommends almond farmers monitor their orchards for spider mites and six-spotted thrips to determine whether treatment is necessary.
During the 2017 growing season, about 517,000 acres of almonds in California received a preventative miticide application in May; 93% were treated with the insecticide abamectin.
“This strategy runs counter to sustainable integrated pest management practices,” Tollerup said. “The sprays adversely impact spider mite natural enemies and are based on the calendar, not on the monitoring and economic thresholds that the UC Statewide IPM program has determined help reduce pesticide applications.”
The heavy reliance on abamectin has also caused some spider mites in the mid-San Joaquin Valley to become 16 times more resistant to the miticide than susceptible populations.
Tollerup worked with the Almond Board of California and a large grower in Kern County to compare the effectiveness of the preventative miticide spray with plots that were simply monitored for pests and natural enemies.
“Tollerup and other UCCE advisors have correctly identified the problem and spoken out both in public and private about not treating unless economic thresholds have been met,” said a pest control adviser working in Kern County. “Because of Tollerup's role, we have been able to collaborate with farmers to hold off on spring treatments at many ranches and only treat when warranted, which has essentially removed a spray treatment on a vast number of acres.”
Surveys conducted after the trial results were released showed that 80,000 acres of almonds were not treated with miticide sprays in May 2018 and May 2019. The change in strategy resulted in a savings to farmers of about $2.2 million in miticide and application costs.
Moreover, Tollerup calculated a subsequent reduction of 880,000 pounds of carbon dioxide emissions due to reduced use of diesel tractors and motor-driven application equipment associated with the miticide spray.
For more information on integrated pest management of spider mites, see the UC Integrated Pest Management website and IPM of spider mites on almond improves farm profitability and air quality.
Road side stands selling fresh strawberries and vegetables are opening up around the San Joaquin Valley, and are a excellent option for safe shopping, reported Dale Yurong on ABC 30 News in Fresno.
In keeping with social distancing guidelines, Yurong conducted remote interviews with UC Cooperative Extension advisor Ruth Dahlquist-Willard and agricultural assistant Michael Yang, who work closely with small-scale farmers in Fresno and Tulare counties.
Dahlquist-Willard suggested customers maintain a six-foot space from other shoppers at farm stands and follow other common sense precautions when purchasing the healthful fresh food by, "not touching any produce that you're not planning to buy, leaving as soon as you've made a purchase and washing the produce when you get home . . . . Similar to what we're seeing at farmers markets right now."
Some valley farmers have been selling their produce at farmers markets out of town and have noticed fewer people are out shopping, Yurong said. They hope more people will stop by the local farm stands, away from the crowded grocery stores, and pick up something straight out of the field.
"My farmers that go to farmers markets, even though the farmers market is still open, they only allow a few people at a time. You don't have a lot of customers walk by just like before," Yang said.
San Joaquin Valley strawberry stands were all expected to be open by April 10, Yurong said.