Posts Tagged: Brad Hanson

USDA approves release of weevil to control yellow starthistle

The USDA has announced it will allow the release of a weevil (Ceratapion basicorne) in the United States to help control yellow starthistle, an invasive weed found in 40 of the lower 48 states, reported Capital Public Radio. The weevils will initially be released in California.

Ceratapion basicorne is native to Eurasia, the same area where yellow starthistle originated. Yellow starthistle is thought to have been introduced into California from Chile during the Gold Rush. The weed readily took hold in California valleys and foothills, thriving in areas where the soil has been disturbed by animals grazing, road construction and wildland firebreaks. Today, yellow starthistle is a very common sight in vacant lots and fields, along roadsides and trails, in pastures and ranch lands, and in parks, open-space preserves and natural areas.

Capable of growing six feet tall and bearing flowers surrounded by inch-long spines, yellow starthistle reduces land value, prevents access to recreational areas, consumes groundwater and poisons horses.

Brad Hanson, UC Cooperative Extension weed specialist at UC Davis, says yellow starthistle thrives in part because of its prickly spines.

"It's not very palatable to any livestock, especially once it's started to flower . . . . Often times, the other grasses and more palatable plants are grazed and the starthistle persists and is sort of the only thing left,” he said.

Hanson says yellow starthistle can be managed on a small scale with chemicals, but that method just doesn't work with the scale of infestation in the state.

“It's difficult to control economically on the millions and millions of acres of rangelands or non agricultural lands that are sort of minimally managed,” he said.

The USDA's environmental assessment of the weevil found no significant impact of its release, besides helping to control yellow starthistle infestations.

Monthly news round up: January 2018

Woodland as ag hub topic of forum

(Woodland Daily Democrat) Jenice Tupolo, Jan. 30

Developing Woodland as an agricultural center is becoming more of a reality, even as local organizations worked together in creating a forum focused on agricultural innovation in Yolo County.

...The city of Woodland, AgStart, UC Agricultural and Natural Resources, and the city's Food Front initiative hosted keynote speaker and vice president of the UC ANR, Glenda Humiston, at the conference.

http://www.dailydemocrat.com/business/20180130/woodland-as-ag-hub-topic-of-forum

Small Farmers in Fresno Hope for Big Moringa Payoff

(KQED) Katrina Schwartz, Jan. 26

The Mouas, along with other Hmong farmers growing moringa, have been working with farm advisers at Fresno County's UC Cooperative Extension to learn how to dry, powder and store their moringa so they can expand into new markets. Most farmers sell it fresh, but most of the health food craze exists around moringa powder, often imported from India.

… “Value-added products are a great way for a small family farm to increase their income,” said Ruth Dahlquist-Willard, a small-farm adviser with the program. Many farmers are accustomed to only selling fresh produce. They plant a diverse set of crops in a small area and sell a little bit of everything. Producing a product that requires the extra step of drying, grinding and storing is a whole new world for many of them.

“I think there's a lot of opportunity there,” Dahlquist-Willard said. She's particularly excited about how a product might bring the younger generation back to their family farms. Kids who have gone off to college for business, marketing or graphic design might see a new kind of future for themselves on the family farm with a product like moringa.

https://ww2.kqed.org/news/2018/01/26/small-farmers-in-fresno-hope-for-big-moringa-payoff/

SLO County's Top 20 Under 40: Meet the 2017 award winners

(San Luis Obispo Tribune) Staff, Jan. 26

…Katherine E. Soule, 35, is director of the UC Cooperative Extension for SLO and Santa Barbara counties, where she's earned state and national recognition for improving community health and increasing diversity in youth participation.

As the extension's youth, families and communities advisor for the last several years, Soule developed new 4-H programs engaging underserved youths and promoting healthy living, leadership and social development. Her efforts nearly doubled enrollment and boosted Latino participation 26.8 percent. She's delivered nutrition education to more than 10,000 people through various partnerships.

http://www.sanluisobispo.com/news/business/article196536784.html

Flooding alfalfa for groundwater recharge

(Morning Ag Clips) Jan. 24

A rigorous field study in two California climate zones has found that alfalfa can tolerate very heavy winter flooding for groundwater recharge. The research was published online Jan. 16 in California Agriculture journal.

The alfalfa research is the latest in a series of projects studying the effects of using land planted with permanent crops – including almond orchards and vineyards – to capture and bank winter storm water. Such projects have great promise but also require collaboration across multiple jurisdictions and agencies. UC Agriculture and Natural Resources vice president Glenda Humiston has made groundwater recharge on working lands and open spaces a division priority and is working with water and land use leaders around the state to facilitate it through policy recommendations and cross-agency collaboration.

https://www.morningagclips.com/flooding-alfalfa-for-groundwater-recharge/

Band Canker Affecting Younger Almonds

(California Ag Today) Patrick Cavanaugh, Jan. 24

Brent Holtz is a UC cooperative extension Pomology Farm Advisor for San Joaquin County. He recently told California Ag Today about how the fungus band canker on almonds is becoming more prevalent in the San Joaquin Valley.

“I've seen a lot more band canker, which is caused by a pathogenic fungus, Botryosphaeria dothidea, and we're seeing it on young orchards, especially in in San Joaquin county," said Holtz.  "We've seen that a lot out in the delta and we've seen it in eastern San Joaquin county where the soils tend to be a little heavier, maybe old dairy ground and richer and we don't really know why."

https://californiaagtoday.com/band-canker-affecting-younger-almonds/

CCOF Annual Conference to Focus on Organic Hotspots

AgNet West) Jan. 22

Registration is available for the California Certified Organic Farmers (CCOF) annual conference, Organic Hotspots: Revitalizing Rural America.  The event is scheduled for February 22 and 23 at the Sheraton Grand Sacramento Hotel in Sacramento.…

The event will focus on organic hotspots and how rural economies can potentially be stimulated by organic production.  Topics will include partnerships between elected officials and the organic community, the role of education and research, along with the process of growing organic produce in local communities.  The event will conclude with a keynote speech from Glenda Humiston, Vice President of the University of California Division of Agriculture and Natural Resources.

http://agnetwest.com/ccof-annual-conference-organic-hotspots/ 

California Today: 100 Million Dead Trees Prompt Fears of Giant Wildfires

(New York Times) Thomas Fuller, Jan. 19

The more than 100 million trees that died in California after being weakened by drought and insect infestations have transformed large swaths of the Sierra Nevada into browned-out tree cemeteries. In some areas more than 90 percent of trees are dead.

This week a group of scientists warned in the journal BioScience that the dead trees could produce wildfires on a scale and of an intensity that California has never seen.

…“It's something that is going to be much more severe,” said Scott Stephens, a professor of fire science at Berkeley and the lead author of the study. “You could have higher amounts of embers coming into home areas, starting more fires.”

https://www.nytimes.com/2018/01/19/us/california-today-100-million-dead-trees-prompt-fears-of-giant-wildfires.html

Winter's good time for gopher control in nut crops

(Western Farm Press) Cecelia Parsons, Jan. 17, 2018

Tree nut growers who are plagued by gopher invasions in their orchards need to stick with effective control measures if they want to minimize tree losses.

Pocket gophers are common in most nut production areas, says Joe Connell, University of California Cooperative Extension Farm Advisor Emeritus in Butte County. In the absence of cover crops or weeds, they will gnaw on tree roots and trunks, and the hungry vertebrate pests can even girdle — and kill — older trees. Trees with root damage and girdling will lose production, and will be susceptible to crown gall, which weakens their structural strength.

http://www.westernfarmpress.com/tree-nuts/winter-s-good-time-gopher-control-nut-crops

Bloomington nursery's citrus trees to be destroyed by California agriculture department

(ABC7 KABC) Rob McMillan, Jan. 17, 2018

Roxana Vallejo was 12 years old when her parents opened up Santa Ana Nursery in Bloomington. Wednesday, the California Department of Food and Agriculture will be at her business to destroy almost all of their citrus trees. Vallejo said the combined value of the trees is almost $1 million.

"They're all fine, and look at all the new growth, it's pretty good," Vallejo said.

The reason they're being cut down is huanglongbing, or HLB, one of the world's worst citrus diseases. The insect that spreads HLB has taken a strong foothold in Southern California.

"It's estimated that the citrus industry may go commercially extinct unless they can get a handle on this problem," said Mark Hoddle, UC Cooperative Extension specialist at UC Riverside, more than one year ago.

http://abc7.com/food/ie-nurserys-citrus-trees-to-be-destroyed-by-ca-agriculture-department/2959173/

OPINION: Ranchers give thanks

(Ventura County Star) Beverly Bigger, president of the Ventura County Cattlemen's Association, Jan. 16, 2018

The majority of attention and sympathy have rightly gone toward those who lost their homes in the Thomas Fire, but I would like to take a moment to highlight the story of others who have suffered as well. They are largely invisible, hidden among the hills and canyons, but their contribution to the county is significant.

Ventura County is home to a robust and historic cattle industry, one that makes up a $2 million portion of Ventura County's agricultural sector. Ranchers play an important role in land management as well, their grazing operations clearing overgrown brush, reducing the fuel available to wildfires and protecting nearby communities.

In the space of 12 hours, the Thomas Fire ripped through vital grazing land that cattle rely on for their daily feed. Sadly, some animals were also lost to the fire.

With feed and fencing gone, many ranchers had hard decisions to make regarding the future of their operations, and some were not prepared for this kind of disaster. Thankfully, we have dedicated public servants who stepped up to help the cattle industry.

Ventura County Agricultural Commissioner Henry Gonzales, Matthew Shapero from the UC Cooperative Extension, and Donna Gillesby and Bryan Bray of Ventura County Animal Services all reached out to ask what they could do to help.

An emergency program was put in place to supply five days of hay until ranchers could get on their feet. The UC Extension also provided a one-stop location where ranchers could meet with representatives from multiple agencies to apply for assistance programs.

The assistance of these agencies was very much appreciated. We want to thank and recognize them for helping us in our time of need. We look forward to returning to our passion: managing and improving the land and continuing Ventura County's ranching heritage.

http://www.vcstar.com/story/opinion/readers/2018/01/16/ranchers-give-thanks/1038625001/

Farm advisor tests strategies for controlling horseweed

(Ag Alert) Bob Johnson, Jan. 10, 2018

One morning last summer, University of California Cooperative Extension vineyard weed control advisor John Roncoroni displayed a horseweed plant that had grown to more than 10 feet tall in a Yolo County vineyard.

Horseweed, which is widely seen on the sides of the state's highways, is among the glyphosate-resistant weed pests that can develop healthy populations in even well managed vineyards.

"We're really having problems with weeds coming in the fall that are resistant to Roundup," Roncoroni said. "Willow herb is tolerant; it's never been completely controlled by glyphosate."

http://www.agalert.com/story/?id=11460

Pomegranate returns not so wonderful but largest grower says otherwise

(Hanford Sentinel) By John Lindt, Jan. 11, 2018

A few years ago Central Valley pomegranate growers appeared to be riding a rising tide of popularity for pomegranates spurring optimism about the crop's future. Growers, including those in Kings County, enjoyed prices of over $1,700 a ton as recently as 2011.

After a significant planting of new trees, by 2015 pomegranate tonnage was fetching just $450 a ton in Fresno County and falling to $362 a ton in Tulare County according to its 2016 crop report.

…UC Farm Adviser Kevin Day says it's simple economics. “We are seeing both overproduction and lack of demand for pomegranates despite expectations to the contrary."

http://hanfordsentinel.com/news/local/business/another-ag-co-will-relocate-to-make-room-for-hsr/article_bb81b0e9-ef28-55d9-b80f-f352bea38466.html

Western Innovator: Promoting sustainable ranching

(Western Farm Press) Tim Hearden, Jan. 9, 2018

Tracy Schohr has devoted much of her career to promoting sustainability in ranching.

While at the California Cattlemen's Association, she put on an annual “rangeland summit” that brought ranchers together with environmental experts and climate change policymakers.

She also worked on a program to limit ranchers' risk of facing Endangered Species Act violations if they created habitat on their land.

After going back to school to earn her master's degree at the University of California-Davis, Schohr has become a UC Cooperative Extension livestock and natural resources adviser based in Plumas, Sierra and Butte counties. http://www.capitalpress.com/California/20180108/western-innovator-promoting-sustainable-ranching 

Weed Control with Brad Hanson UC Cooperative Extension Weed Specialist at UC Davis 

(California Ag Today) Patrick Cavanaugh, Jan. 8, 2018

“Weeds are probably one of the year-in, year-out problems that growers face,” said Brad Hanson, UC Cooperative Extension, who discussed herbicide resistance with California Ag Today.

https://californiaagtoday.com/podcasts/brad-hanson-uc-cooperative-extension-weed-specialist-at-uc-davis-on-weed-control/ 

Building blocks for tending flocks

(Auburn Journal) Julie Miller, Jan. 7, 2018

Counting sheep is no longer for the tired and sleepy.

Shepherding has become a booming industry in Placer County. At last count, there are 9,000 head of sheep registered with the county, said Dan Macon, livestock and natural resources advisor for University of California, for Placer and Nevada counties. And there may be more sheep that have not been registered, perhaps because they are in a smaller flock of 10 to 15, he said.

Sheep have proven to be versatile. Not only raised for the meat and milk, but also wool fibers, plus, they can help reduce fire danger by eating away tall grasses and shrubs.

http://www.auburnjournal.com/article/1/06/18/building-blocks-tending-flocks#

After a recent outbreak of E.coli, is it safe to eat romaine lettuce? Experts differ

(Fresno Bee) Robert Rodriguez, Jan. 5, 2018

If you are staying away from romaine lettuce because of an outbreak of E.coli, it's understandable. But at least one food safety expert says it may not be necessary.

…But University of California food safety expert Trevor Suslow said it's unlikely the lettuce you buy at the grocery store these days is going to do you any harm. That's because the illnesses happened from Nov. 15 through Dec. 8. Lettuce sold during that period wouldn't be around anymore.

“It's not going to last that long, it's gone,” Suslow said.

http://www.fresnobee.com/living/food-drink/article193301924.html

Cattle Ranchers Join Conservationists To Save Endangered Species And Rangelands

(Forbes) Diana Hembree, Jan. 5, 2018

…California has a strong incentive to preserve its 18 million acres of ranchland: Cattle and calves are the state's fourth-leading agricultural commodities (milk and cream are No. 1), according to state agricultural data. But in a Duke University survey of the state's ranchers, more than half said they were “more uncertain than ever” that they would be able to continue ranching. California is losing an estimated 20,000 acres of rangeland each year, according to the Nature Conservancy, and on any given day ads for the sale of cattle ranches dot the Internet. The median age of California ranchers is 58 to 62, and more are aging out of the business with no children interested in taking over the ranch.

But this trend can be reversed, according to Lynn Huntsinger a professor of environmental science and rangeland ecology at UC Berkeley. To preserve these landscapes for future generations, ranchers need payment and recognition for their ecosystem services “in order to preserve these working landscapes for future generations,” Huntsinger writes.

https://www.forbes.com/sites/dianahembree/2018/01/05/cattle-ranchers-join-conservationists-to-save-endangered-species-rangelands/#56c2400f220d

Months after Wine Country fires, damaged vineyards face uncertainty

(SF Chronicle) Esther Mobley, Jan. 4

…“No one knows what's the real threshold for heat damage,” says Rhonda Smith, the Sonoma County-based viticulture farm adviser for the University of California, who has come to Gilfillan to consult on its rehabilitation.

Much of the conventional wisdom about how fires interact with vines — that vines can't burn, because of their high water content, for instance — didn't turn out to be true for every vineyard, she says.

“In 99 percent of cases, vines were fire breaks,” says Smith. But if there was dry vegetation, if there was wood mulch on the ground, if the soil was especially dry — if, if, if — then they weren't.

http://www.sfchronicle.com/wine/article/Months-after-Wine-Country-fires-damaged-12474309.php

Progress reported on robotic weeders for vegetables

(Ag Alert) Bob Johnson, Jan. 4

The next generation of computer-controlled, automated cultivators will be able to use cameras to remove weeds in the seed line as close as 1 inch from young tomato or lettuce plants, without damaging the crop.

…

“It must be more than half the lettuce acreage that is already using the automated thinners,” said Steve Fennimore, UC Cooperative Extension vegetable weed specialist.

Fennimore is supervising the Salinas lettuce trials of “marking” the crop in order to make this technology practical for weeding as well.

“The weeders already out there tend to be prototypes that people are still experimenting with,” he said.

http://www.dailydemocrat.com/article/NI/20180104/NEWS/180109957

2017's natural disasters cost American agriculture over $5 billion

(New Food Economy) Sam Bloch, Jan. 4, 2018

Over a period of 10 months in 2017, America experienced 16 separate, billion-dollar weather and climate-related disasters. Those weather events carved paths of destruction straight through some of the most fertile and productive regions of the country, wreaking havoc on beef cattle ranches in Texas, soaking cotton and rice farms in Louisiana, orange groves in Florida, and burning up vineyards in California. And that was all before Southern California's still-active Thomas fire, which began on December 4, and then closed in on the country's primary avocado farms. It's now the state's largest-ever, in terms of total acreage.

• Acres of cherimoya trees in Santa Barbara County destroyed by the Thomas fire: 100
• Total dollar value of Santa Barbara cherimoya fruit damaged by fire: $5,000,000

• Acres of avocado fields in Santa Barbara and Ventura Counties threatened by wildfire: 5,260
• Estimated pounds of Hass avocados in Ventura County lost to wildfire: 8,060,000
• Total dollar value of that lost harvest: $10,175,750
• Approximate percentage of American avocado crop threatened by wildfire: 8
• Expected effect of wildfire on avocado prices in America, due to reliance on imports: 0

• Winegrape acreage in Napa and Sonoma Counties: 104,847
• As a percentage of total California winegrape acreage: 22

• Estimated dollar value of unharvested Cabernet grapes in those counties, before the wildfires: $175,000,000
• Estimated dollar value of those grapes, now tainted by smoke: $29,000,000
• Bottles of 2016 Napa Cabernet you can buy for the price of two 2017 vintages, due to winegrape scarcity: 3

California wildfire data from Daniel A. Sumner, Ph.D. of UC Agricultural Issues Center, USDA NASS, Ben Faber, Ph.D. of UC Cooperative Extension Ventura.

https://newfoodeconomy.org/2017-natural-disasters-agriculture-damage-5-billion/

There Is No “No-Fire” Option in California
(Bay Nature) Zach St. George, Jan. 2, 2018

As the use of prescribed fire by Cal Fire declined in recent decades, its use also declined with private landholders, says Lenya Quinn-Davidson, director of the Northern California Prescribed Fire Council, who leads prescribed burning workshops across the state. Scott Stephens, the UC Berkeley professor, concurs. Decades of suppression left the western U.S. with relatively few people trained to carry out the work: “We just don't have that experience to pass on.” But it's important not to let the current enthusiasm pass, he says—as climate change continues to push conditions toward extremes, as wildfires consume more and more of fire agency budgets, and as the wildland-urban interface expands, it will only become more difficult to bring fire back.

https://baynature.org/article/no-no-fire-option-california/

Scientist discusses working on Food Evolution movie

(Brownfield Ag News) Larry Lee, Jan. 1

A scientist involved in a movie about genetically modified food says many don't understand what GM is, let alone the benefits.  Alison VanEenennaam says, “Really, it's a breeding method, and I think the public sector applications for things like disease resistance have very compelling societal benefits that I think most people can relate to.  I don't think we want plants and animals getting sick, and if we can solve that problem genetically rather than using chemicals, I think people get that.”

VanEenennaam is a geneticist at the University of California.  She tells Brownfield there is a lot of unnecessary fear about eating genetically modified food.  “The safety around GM (Genetically Modified) has been established and is, you know, agreed on by every major scientific society in the world and yet we've got the vast majority of consumers that don't believe that.”

https://brownfieldagnews.com/news/scientist-discusses-working-food-evolution-movie/

Urban Edge farm program offers immersion-style learning

(East Bay Times) Lou Fancher, Jan. 1, 2018

After operating a pilot version of the ambitious program, a $200,000 grant from the USDA National Institute of Food and Agriculture's Beginning Farmer and Rancher Development Program is a launch pad for the immersive learning experience.

For the first cohort of students, many of them women and/or people of color, immigrants, refugees, veterans or farmers-to-be with limited resources, the land is a classroom. Instruction comes from First Generation and experts from the National Center for Appropriate Technology and UC Cooperative Extension. Participation in the program represents opportunity and fulfills dreams the first-time farmers hold of agricultural avocation, economic stability, families, homesteads and permanence.

https://www.eastbaytimes.com/2018/01/01/urban-edge-farm-program-offers-immersion-style-learning/

Tribute to Paul Verdegaal – one of Lodi's “men behind the curtain”

(Lodi Wine blog) Randy Caparoso, Jan. 1, 2018

This coming February 6, 2018, Lodi winegrowers will get together for their 66th Annual LODI GRAPE DAY. They will also mark the occasion with a celebration of the retirement of Paul Verdegaal, who has been working full-time as San Joaquin County's viticulture, bush berry and almond Farm Advisor under the auspices of UCCE (University of California Cooperative Extension) since 1986.

http://www.lodiwine.com/blog/Tribute-to-Paul-Verdegaal---one-of-Lodi-s--men-behind-the-curtain-

Root out weed problems with upcoming courses at UC Davis

Weeds are a pervasive and expensive problem in California. They can choke waterways, crowd out native species on rangeland, and rob farmers of crop yields. According to the California Invasive Plant Council, the annual cost of invasive plant work in California is at least $82 million.

The University of California has robust educational resources to help those engaged in the battle, and this summer UC Davis and UC Agriculture and Natural Resources personnel are offering a trio of programs to help in the effort.

Weed Day: July 7, 2016

The 60^th annual Weed Day will be held at UC Davis on July 7 from 8 a.m. to 4:30 p.m. The program gets under way in the Buehler Alumni Center.

Weed Day will be of interest to pest control advisers, chemical company cooperators, faculty, students and regulatory officials. It is an opportunity to learn about the latest research and to visit current weed-control field trials. The event begins with a bus tour to the research plots. Following lunch, staff and students will present information on projects that are either not in-season or located too far off campus for viewing.

“We have tomatoes, walnuts, and almonds, as well as aquatic research results, and a weed identification quiz,” said professor and UC Cooperative Extension specialist Kassim Al-Khatib, chair of this year's event. “We'll be hearing about control of medusahead, management in grapes, a new herbicide for rice, and many studies on herbicide resistance issues.”

For additional information and to register.

Diagnosing Herbicide Symptoms: July 8, 2016

The Weed Research and Information Center at UC Davis is offering a new course, Diagnosing Herbicide Symptoms, on July 8 at the Bowley Plant Science Teaching Center.

This program will be of interest to pest control advisers, chemical companies, field investigators and insurance adjusters. The course focuses on how an herbicide injury situation can arise, what information can help diagnose herbicide problems during field investigations, and what tools are available.

Topics include herbicide modes of action, symptom development, recovery from herbicide injury, economic damage, and other areas. Instruction takes place in a lecture, field visit, and hands-on demonstrations. Course instructors include UC Cooperative Extension (UCCE) specialists Kassim Al-Khatib and Brad Hanson, UCCE farm advisor John Roncoroni, and Napa County Agricultural Commissioner Greg Clark.

For additional information and to register.

Aquatic Weed School: Sept. 7–8, 2016

The Aquatic Weed School will be held Sept. 7–8 at the Bowley Plant Science Teaching Center.

This intensive course is designed for those involved in consulting, research and management of aquatic weed systems throughout the western United States. Topics include ecological classification and impacts of aquatic weeds, biology of aquatic weeds, physical and chemical characteristics of aquatic ecosystems, regulatory issues, developing an aquatic management plan, aquatic weed identification, equipment demonstration, adjuvants and surfactants for aquatic systems, pest prevention for aquatic weeds, physical and mechanical control methods, biological control, chemical and non-chemical control, and a case study of a complex management plan.

For additional information and to register.

Need more information? Contact Gale Pérez with the UC Weed Research and Information Center, (530) 752-1748, gperez@ucdavis.edu.

Weed day revisited on Capital Public Radio

UC Cooperative Extension weed specialist Brad Hanson was featured on the Capital Public Radio program Insight, an in-depth interview show hosted by environmental reporter Jeffrey Callison. The interview came a day after the 55th annual Weed Day at UC Davis.

In the 8-minute segment, which runs from about 23:50 to 31:30 in the hour-long show, Hanson outlined Cooperative Extension weed management research.

"Weeds are a tremendous problem for farmers in every cropping system," Hanson said. "In contradiction to some other pests, weeds don’t spike. They are a constant problem. Farmers are spending money on weed control and trying to minimize productivity declines from weeds competing for water, fertilizer and sunlight."

Hanson said much of UC's weed research looks at chemical control, the approach used by 85 percent of farmers.

"We try to find the most efficient rates, most effective chemicals, and the least environmentally damaging products," he said.

Callison seemed intrigued by the fact that weed seeds can lie dormant in soil for years and even decades.

"It is said, one years seeding is 10 years weeding. That’s probably an underestimate," Hanson said.

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