University of California, Division of Agricultural and Natural Resources

UC Master Gardeners empower college students to garden for mental wellness

Courtesy of the UCANR News 

Although training is required to become a University of California Master Gardener, the benefits of gardening can be experienced by anyone and everyone.

“As long as you’re willing to get your hands dirty,” said Laurie Menosky, a UC Master Gardener volunteer in Orange County, “you can learn to grow all sorts of things.”

In early April, Menosky partnered with ETN Medical Infusion (a clinic in Orange County) and the Sustainability Program for Student Housing at UC Irvine to teach students how to grow tomatoes. Menosky welcomed all in attendance, including families with toddlers who seemed fascinated by the 60 tomato plants atop one of the tables in the room.

The UC Master Gardener Program is a part of UC Agriculture and Natural Resources. During her presentation, Menosky taught participants how to choose varieties that fit their taste and growing environment, how to cultivate a thriving environment, and how to control pests and diseases using integrated pest management practices.

“We have 16,000 residents at UCI and sustainability is one of our values. One of the ways we engage students is through on-campus gardens,” said Rachel Harvey, sustainability program manager for UCI Student Housing and a UC Master Gardener volunteer in Orange County.

UC Irvine has one teaching garden reserved for undergraduate learning, and three gardens operated and maintained by graduate students. “I was on the waiting list for a garden plot for a while, but it was totally worth the wait,” said Johanna Rinaman, a fifth-year Ph.D. student studying physical chemistry.

While the highlight of the event for many people was the opportunity to take a tomato plant home, another important takeaway was how gardening can be a good activity for your mental health. Sarah Nghiem, family medicine specialist at ETN Medical Infusion, who worked closely with Menosky, was instrumental in developing the mental health content for the day, encouraging attendees to attempt gardening with a mental health perspective.

Nghiem and her team received funding from the Orange County Health Care Agency through the Mental Health Services Act to work with transitional aged students (15-24 years-old) on understanding the importance of mental health, which led to the collaboration between UC Irvine, her alma mater, and the UC Master Gardeners of Orange County.

“I didn’t do any gardening during the winter, and I felt a lot more anxious and depressed during that time,” Rinaman said. “I know gardening improves mental health because I’ve immediately felt a difference whenever I spend time with plants.”

Rinaman, whose father taught her a lot of what she knows about gardening, said that having access to a 4 feet by 6 feet plot to grow her own food is one of the many things she loves about UC Irvine.

Like Rinaman, Menosky turns to gardening to decompress, especially during the long days of summer. Teaching others about the physical and mental benefits of gardening gives her an opportunity to share her experience and, hopefully, help others find new ways to manage stress.

“We often have attendees come back years later telling us how our information has helped them and how much more they are enjoying their time in their gardens,” she said.

To conclude her presentation, Menosky instructed participants to line up for their own tomato plant. Attendees took their plants outside to transfer them from a small pot to a grow bag – a type of container that helps root structure development.

Cassie Ekwego, a third-year transfer student studying civil engineering, couldn’t hide her excitement after carefully lifting her plant. “I don’t think I realized how attentive you need to be when working with plants,” said Ekwego, reflecting on what she learned from Menosky’s presentation.

Now that she has her own plant to care for in her own home, Ekwego is eager to put her new knowledge to the test. “I love tomatoes, but this is going to be a huge responsibility for me,” she said.

Randy Musser, UC Master Gardener program coordinator for Orange County, said that while he enjoys talking to avid gardeners, bringing gardening to new people in the community is special to him. “This tomato workshop is particularly exciting for me because it is an opportunity for the UC Master Gardeners to grow our connection to UCI and young people just starting off on their gardening journey,” said Musser.

With a generous contribution from UC Master Gardener volunteer Sheila Peterson, Musser was able to purchase enough supplies to help attendees, like Ekwego, jumpstart their gardening experience.

Students, whose stress levels can skyrocket throughout the school year, value opportunities to be outdoors, try something new and be in community. “The garden is a different type of classroom. It’s a place where students can learn and experiment, hopefully in a way that reduces stress,” said Harvey of UCI Student Housing.

Ekwego, who tried gardening for the first time while volunteering at UC Irvine’s teaching garden, is just one of the many students inspired by their experiences. “Gardening reminds me that it’s OK to get my hands dirty,” Ekwego said.

2024-05-15T08:24:50-07:00May 15th, 2024|

New UC study estimates blackberry production costs

A new study that can help growers and other readers estimate costs and potential returns for blackberries grown on California’s Central Coast was recently released by UC Agriculture and Natural Resources, UC Cooperative Extension and the UC Davis Department of Agricultural and Resource Economics.

“The study provides growers with a baseline to estimate their own costs, which can help when applying for production loans, projecting labor costs, securing market arrangements or understanding costs associated with water and nutrient management and regulatory programs,” said Brittney Goodrich, UC Cooperative Extension specialist and study co-author.

The cost study models a management scenario for a 30-acre farm, 15 acres of which are planted to blackberries. The remaining acres are planted to other berries or are used for the irrigation system, roads and buildings. The authors describe the cultural practices used for the establishment, production and harvest of blackberries, including land preparation, soil fertility and pest management, irrigation and labor needs.      

The 28-page study shows costs for each operation, material inputs and costs, and cash and non-cash overhead costs in a variety of formats for an establishment year and then four additional production years. A ranging analysis for the four production years is also included and shows potential profits or losses over a range of prices and yields.

The new study, titled “2024 Sample Costs to Establish, Produce and Harvest Blackberries” can be downloaded from the UC Davis Department of Agricultural and Resource Economics website at https://coststudies.ucdavis.edu.  

For a detailed explanation of the assumptions and calculations used to estimate the costs and potential returns, readers can refer to the narrative portion of the study. 

Sample cost of production studies for many other commodities grown in California are also available on the website.

For more information, contact Mark Bolda, University of California Cooperative Extension farm advisor, at mpbolda@ucanr.edu or Jeremy Murdock in the UC Davis Department of Agricultural and Resource Economics at jmmurdock@ucdavis.edu.

2024-05-07T08:05:45-07:00May 7th, 2024|

Innovators in academia gear up for VINE Build workshops

Courtesy of UCANR

A series of VINE Build workshops aimed at equipping academic innovators with essential pathways to bring new inventions to market is being sponsored by The VINE, an initiative of University of California Agriculture and Natural Resources (UC ANR), in collaboration with Farmhand Ventures. These workshops are designed to empower participants with the knowledge and tools necessary to navigate the complex landscape of technology commercialization.

“These workshops represent a unique opportunity for academic innovators to gain invaluable insights into the commercialization process,” said Gabe Youtsey, UC ANR chief innovation officer and founder of the VINE. “By bridging the gap between academia and industry, we aim to catalyze innovation and propel advancements in technology and agriculture so we can enjoy the benefits sooner.”

The half-day sessions will explore various aspects of commercialization as a mechanism for technology transfer. Led by industry experts, the workshops will cover user-centered design principles, inclusive innovation basics, the role of commercialization in technology translation, commercialization strategies, intellectual property licensing, transitioning from academia to business, and the differences between non-dilutive and dilutive funding.

“For academics looking to make a real impact, these workshops provide an invaluable platform,” said Connie Bowen, co-founder and managing partner of Farmhand Ventures. “By participating in these sessions, innovators have the opportunity to turn their great ideas into tangible products that address the big challenges facing our industry today.”

People involved in applied food and agriculture research – including professors, graduate students, undergraduate students and others  – are encouraged to participate.

The workshops will be held across various locations in California on the following dates:

●      Fresno: May 9, 8:30 a.m. – 2 p.m., Smittcamp Alumni Center, Fresno State

●      San Diego: May 23, 8:30 a.m. – 2 p.m., Salk Institute Foyer, San Diego

●      Davis: May 29, 8:30 a.m. – 2 p.m Physical Sciences and Engineering Library, Conference Room, UC Davis

●      Santa Cruz: Date and location to be determined.

For more information and to register for the workshops, please visit: https://bit.ly/vine-build-workshop

2024-05-07T08:00:49-07:00May 7th, 2024|

Water risks to agriculture: Too little and too much

Courtesy of  UCANR

Report recommends policies, programs and tools for farm resilience

Water is among the most precious resources on the planet. Some areas don’t get enough; some get too much. And climate change is driving both of those circumstances to ever-growing extremes.

Two UC Merced experts in civil and environmental engineering took part in a recent report by the Environmental Defense Fund examining the issue and potential solutions. Associate Professor of Extension Tapan Pathak and Professor Josué Medellín-Azuara co-authored the report, “Scarcity and Excess: Tackling Water-Related Risks to Agriculture in the United States,” and wrote the section pertaining to California.

In addition to climate change, disruptive human interventions such as groundwater over-extraction, sprawling drainage networks and misaligned governance are driving up water-related agricultural costs, particularly in midwestern and western states, the researchers found.

The problem is magnified in California, which hosts the largest and the most diverse agricultural landscape in the U.S., Pathak and Medellín-Azuara wrote, with gross revenues from farms and ranches exceeding $50 billion.

“Due to the favorable Mediterranean climate, unique regional microclimate zones, a highly engineered and developed water supply system, and a close connection between producers and research and cooperative extension institutions, California’s agricultural abundance includes more than 400 commodities, some of which are produced nowhere else in the nation,” the UC Merced researchers wrote.

But the state’s varying climate and water needs pose a challenge. Though most of the precipitation falls in the northern part of California, the southern two-thirds of the state account for 85% of its water demand. And all of those crops must be watered in the summer, when there is little, if any, rainfall.

Some of the water comes from snowpack developed through winter storms and stored in reservoirs as it melts. Much of it comes from the Colorado River.

“Substantially less water is captured and stored during periods of drought, imperiling California’s water supply and putting agricultural water needs at risk,” Pathak and Medellín-Azuara wrote.

Climate change, with increasing periods of drought between excessively wet winters, magnifies that risk.

“Further, the rate of increases in the minimum temperatures in the Sierra Nevada is almost three-fold faster than maximum temperatures, resulting in potential decrease in the snowpack, earlier snowmelt, and more water in liquid form as opposed to snow,” the researchers wrote. “According to the California Department of Water Resources, by 2100, the Sierra Nevada snowpack is projected to experience a 48% to 65% decline from the historical average.”

Climate change is also expected to affect the availability of water from the Colorado River.

Climate extremes such as heat waves, drought and flooding – giving rises to increased weeds, pests and disease – are already significantly impacting agriculture and the broader economy, Pathak and Medellín-Azuara wrote.

The state’s drought from 2012 to 2016 led to about 540,000 acres of fallow farmland in 2015, costing the state’s economy $2.7 billion in gross revenue and 21,000 jobs. With the lack of precipitation, farmers increasingly pumped groundwater to irrigate crops, depleting those resources.

The report goes on to recommend policies, programs and tools be developed for agricultural resilience, including:

  • Changing land use and crop management practices to support a transition to an agriculture footprint that can be sustained by the available water supplies.
  • Increasing farmer and water manager access to important data and innovative technological tools to support their efforts.
  • Reimagining built infrastructure and better using natural infrastructure so regions are better equipped to handle weather extremes.
  • Developing policy and funding mechanisms to support mitigation and adaptation to water-related risks, avoid maladaptation and ensure food and water security.

“California’s innovative agriculture needs to rapidly adapt to more volatile water availability, climate-driven higher water demands, and regulation protecting groundwater reserves, communities and ecosystems,” Medellín-Azuara said. “The early adoption of more sustainable practices in agriculture will likely pay off dividends both in the short and long terms.”

Added Pathak, “California faces significant challenges related to climate change, but it also presents opportunities for innovations, collaborations and sustained growth. To make agriculture resilient to climate risks, we need to engage in holistic solutions that integrates environmental, social, economic and policy considerations.”

2024-03-19T10:25:04-07:00March 19th, 2024|

What Are Atmospheric Rivers and How Can I Capitalize On All This Rainfall?

Courtesy of UCANR

The 2024 rainy season in Southern California has intensified, with recent storms causing significant damage and life-threatening flooding. Daniel Swain, a dedicated UCLA researcher specializing in the analysis of evolving weather patterns influenced by climate change, warned of “bomb cyclone” conditions driven by air current anomalies off the West Coast. His detailed insights, outlined in a February 3rd blog post on Weather West, sheds light on recent weather events.

Despite the apprehension surrounding these storms, it’s crucial to acknowledge the vital role atmospheric rivers play in replenishing water supplies in western states. The current situation marks a stark contrast for Californians, who only a few years ago grappled with historic drought conditions. Are you curious how much rain fell in your area? You can track rainfall totals through the Ventura County Watershed Protection District rainfall map. Click on the boxes and see how much rain fell in the last day, week or season.

Those residing in low-lying areas or flood-prone regions can acquire free sandbags to safeguard their properties during future rain events. On a positive note, excess rainfall presents an opportune time to invest in rain barrels and rain-harvesting systems. Rainwater harvesting, a time-tested practice dating back to ancient times, is experiencing a resurgence. On a large scale, the Freeman Diversion redirects water from the Santa Clara River during storms to spreading basins for groundwater recharge.

For the homeowner, installing rain barrels is a straightforward process, with ample online resources such as books and videos. “Rainwater Harvesting for Drylands and Beyond,” by Brad Lancaster, stands out as a go-to guide. Additionally, the creation of rain gardens can facilitate the capture of water in the soil. This natural process allows plants and microorganisms to break down organic compounds and filter out pollutants commonly found in urban stormwater runoff.

Explore discounted rain barrels and other water conservation devices offered by local municipalities.

2024-02-13T09:21:53-08:00February 13th, 2024|

Key Climate Data Added to Enhance Grower Decision-Support Tool

By Pam Kan-Rice UCANR

Free CalAgroClimate tool helps growers protect crops from frost and extreme heat

California farmers can see how climatic conditions that may affect agriculture are changing in their regions by using CalAgroClimate so they can make strategic changes. Nine new agriculturally important climate indicators have been added to the decision-support tool created by UC Cooperative Extension and U.S. Department of Agriculture scientists.

These new tools use a high-resolution climate dataset called PRISM to provide location-specific or county-aggregated long-term trends in agroclimatic indicators from 1980 to last year. These new agroclimate indicators include Frost Days, Last Spring Freeze, First Fall Freeze, Freeze-Free Season, Tropical Nights, Hot Days, Extreme Heat Days, Heatwaves and Diurnal Temperature Range (see definitions below). These indicators were derived from a study published in the journal Agronomy.

All of the new tools are free and available on CalAgroClimate for anyone to access.

“Frost-related tools such as Frost Days, Last Spring Freeze, First Fall Freeze, and Freeze-Free Season can help farmers and agricultural clientele make informed long-term choices,” said Tapan B. Pathak, UC Cooperative Extension specialist in climate adaptation in agriculture based at UC Merced, who is leading the CalAgroClimate project.

“For instance, if you are planning to invest in a frost sensitive crop in your region, these indicators can provide valuable information on whether frost risk has changed over time and whether it is less risky to make such an investment,” he said. “Wine grapes, for instance, are very sensitive to frost. Although not all frost events are damaging, understanding long-term trends in frost can help in making long-term strategic decisions such as whether to invest in frost protections.”

Another set of new agroclimatic indicators, on CalAgroClimate – Tropical Nights, Hot Days, Extreme Heat Days, Heatwaves and Diurnal Temperature Range – are based on higher maximum and minimum temperatures. Tropical Nights, for instance, calculates total number of nights when overnight temperatures exceed 68 F. More frequent tropical nights can increase crop respiration rates and can be detrimental for fruit quality and quantity, increase the risk of damage from pathogens, and potentially impact fruit set and yield.

Knowing how trends are evolving over time can assist growers in managing their crops to reduce risks. Similarly, growers can easily look at trends related to heat – hot days, extreme heat and heatwaves – on CalAgroClimate to assess their options on what they need to do to be adaptive. In the short term, growers may put up shade or for longer term, choose varieties that are more heat-tolerant.

“In recently published work, one of the farmers in the Central Valley told us, ‘When you really see so much difference in a short amount of time in your immediate area…we would have to look at that and say, well, we’re going to have to adapt varieties because this is a 20- or 25-year planting and we’re going to have to find crops or varieties that will adapt to that,’” Pathak said.

Another farmer told us, “Knowing what’s going to happen or at least having a good idea, if you know something’s going to be become or won’t be viable, then obviously you’re going to try to phase that out, and phase in something that’s better suited.”

Pathak added, “The new agroclimatic indicators on CalAgroClimate provide a reality check on how conditions are changing in short and long-term, what it means for farmers and to assist them on deciding what they need to do to be adaptive. These tools will greatly benefit farmers and agricultural clientele in assessing risks and making informed decisions.”

Other collaborators include Steven Ostoja and Lauren Parker of the USDA California Climate Hub, Prakash Kumar Jha of UC Agriculture and Natural Resources and Robert Johnson and Shane Feirer of UC Agriculture and Natural Resources’ Informatics and Geographic Information Systems.

Definitions of AgroClimatic Indicators:

Frost Days are days in a year with minimum temperature below or equal to 32F.

Last Spring Freeze is the latest day in spring when minimum temperature is below or equal to 32F.

First Fall Freeze is the earliest day in fall when minimum temperature falls to 32F or below.

Freeze-Free Season is the time between the last spring and first fall freeze, represented by the number of consecutive days in a year without freezing temperatures.

Tropical Nights are number of nights when temperatures exceed 68F.

Hot Days are the days per year with maximum temperature exceeding 100 °F.

Extreme Heat Days are the number of days per year with maximum temperatures warmer than the 98th percentile of historical summer maximum temperature for the selected location.

Heatwaves are events that occur when extreme heat lasts for at least three consecutive days.

Diurnal Temperature Range is the difference between daily maximum and minimum temperatures.

2023-05-12T12:40:25-07:00May 12th, 2023|

Hales to Join UC ANR Leadership Team

By Pam Kan-Rice, UCANR

Higher education leader is known for his work with underrepresented communities

Brent Hales will be joining University of California Agriculture and Natural Resources as the new associate vice president for research and Cooperative Extension beginning July 1. 

“After a nationwide search, Brent emerged as a proven and respected leader who will help us to strengthen partnerships, build trust, address challenges and define our 2040 strategic vision,” said Glenda Humiston, UC vice president for agriculture and natural resources. 

Hales brings over 20 years of higher education research and leadership experience, including at land grant institutions and in Cooperative Extension. He currently serves as an associate dean of Pennsylvania State University’s College of Agricultural Sciences and director of Penn State Extension. 

“I am very excited to join the UC ANR family,” Hales said. “My grandfather was a 1939 graduate of the University of California, Berkeley and both of my parents grew up in California.”

Before joining Penn State in 2019, he served as the senior associate dean and chief financial officer of the University of Minnesota Extension, associate dean for the University of Minnesota Extension Center for Community Vitality, and the director of the Economic Development Authority Center at University of Minnesota, Crookston.

His research focuses on holistic community and economic development and entrepreneurship. He has spent his career working across the United States and the globe with underrepresented communities. Since 1998, Hales has worked with Native American Nations in asset development and capacity building. 

“I am excited to collaborate with California’s Native Nations, urban residents and underinvolved Californians as they seek to achieve their goals,” Hales said. “Some notable areas are tackling climate change, food security and workforce development.”  

“What excites me most is to be part of the leadership team for the premier institution of Ag and Natural Resources research and extension in the United States,” Hales said. “The people, the facilities, the opportunities and the engagement with the communities and organizations of California is second to none.”

Hales earned a Ph.D. in rural sociology from Iowa State University, a master’s degree in sociology from Middle Tennessee State University and a bachelor’s degree in sociology from Brigham Young University in Utah.

He is the father of six children, is the grandfather of six grandchildren and has been married to his best friend Candy for over 30 years.

Deanne Meyer, UC Cooperative Extension livestock specialist, has been serving UC ANR as interim associate vice president for research and Cooperative Extension over the past year and is assisting Hales with the transition.

UC Agriculture and Natural Resources brings the power of UC to all 58 California counties. Through research and Cooperative Extension in agriculture, natural resources, nutrition, economic and youth development, our mission is to improve the lives of all Californians. Learn more at ucanr.edu and support our work at donate.ucanr.edu.

2023-05-11T11:58:57-07:00May 11th, 2023|

Wet Orchard Floors Could Cause Phytophthora Problems

By Patrick Cavanaugh, with the Ag Information Network

With all the rainfall in many parts of the state, standing water in orchards could be a problem to those trees as it could cause anaerobic situations. Katherine Jarvis-Shean is a UCANR farm advisor based in Yolo County with additional coverage in Solano and Sacramento counties. She noted problems if that water stays standing deep in orchards.

The danger zone comes after, say four days or so, in terms of having anaerobic responses. Certainly, if you’re sitting in moisture and saturated soil for more than 24 hours, you’re in the danger zone with phytophthora infections. Which is a serious fungal disease,” she said.

“And we’re even looking at some water lines above the root zone crown. So then you get water just on a pure almond scion that can, it’s very vulnerable to phytophthora, especially aerial phytophthora,” noted Jarvis-Shean.  “It’s a good year to stay on top of your phytophthora management in terms of phosphite, and other potential phytophthora treatments for those wet orchards,” she said.

2023-04-12T11:35:13-07:00April 12th, 2023|

UC Agriculture and Natural Resources statements on Richard Rosenberg’s death

Richard Rosenberg, former chairman and CEO of the Bank of America, died Friday, March 3. He was 92. When Rosenberg retired from BofA in 1996, the bank honored him by endowing the Rosenberg International Forum on Water Policy at UC Agriculture and Natural Resources. 

Glenda Humiston, University of California vice president for agriculture and natural resources:

“Dick Rosenberg is well-known for his generous gifts to the University of California and to the Bay Area. With his Bank of America endowment gift to UC Agriculture and Natural Resources to create the Rosenberg International Forum on Water Policy, he has had the most far-reaching and profound impact. Over the years, Dick developed an understanding of the complex and contentious water issues in California and across the globe. His intent in bringing together scientists and policymakers from around the world to discuss water management was to reduce conflicts surrounding this critical resource. While we continue to face challenges of water scarcity and water quality, we are able to solve some issues by sharing our knowledge and experiences. For years to come, the global community will benefit from Dick Rosenberg’s foresight to fund the International Forum on Water Policy.”

Soroosh Sorooshian, UC Irvine Distinguished Professor and director of the Center for Hydrometeorology and Remote Sensing and chair of the UC ANR Rosenberg International Forum on Water Policy:

“Mr. Richard Rosenberg was passionate about the well-being of the environment in addition to his responsibilities managing one of the largest financial institutions in the world. His concern about water resources scarcity and international water conflicts led to the establishment of the UC ANR Rosenberg International Forum for Water Policy with an endowment gift from the Bank of America to honor Dick’s vision. It is a great honor for the forum to carry the vision of Mr. Rosenberg as a lasting legacy to his commitment to issues related to international water policy.” 

Henry Vaux Jr., UC Riverside Professor Emeritus, UC ANR Associate Vice President Emeritus, Founding Chair of Rosenberg International Forum on Water Policy

Richard Rosenberg made many contributions to the well-being of all Californians. Among those was the rallying of the business community to the cause of managing an earlier severe drought that began in the late 1980s. This expression of his long term-interests in the management of water resources led the Board of the Bank of American to establish the Rosenberg International Forum on Water Policy at the University of California in his honor. Over the years, that Forum has met at 10 locations around the world, often with Rosenberg himself in attendance. The work of the Forum has influenced water policy in countries ranging from Australia to Jordan. As a founding chair of the Forum, I can attest to the crucial role that he played in guiding the establishment of the institution and ensuring its success over two and a half decades. I will miss his wise counsel, sharp insights on almost everything and his great sense of humor. I send my condolences and best wishes to his wife, Barbara, and his family. 

About the Rosenberg International Forum on Water Policy

The Rosenberg International Forum on Water Policy originated in 1996 with an endowment gift from the Bank of America to the University of California. The purpose of the gift was to support a water policy forum in honor of then-retiring Bank Chair and Chief Executive Officer Richard Rosenberg. Rosenberg had a long-term interest in water resources and was credited with rallying the California business community to address the causes and impacts of the drought of 1987-1992.

The Rosenberg Forum is held every other year in different locations around the world. Participation is limited to 50 water scholars and senior water managers. Interactive discussions about the science of water management and different experiences in water management around the globe are at the heart of the forum. 

The first forum was held in San Francisco in 1997, followed by gatherings in Barcelona, Spain; Canberra, Australia; Ankara, Turkey; Banff, Canada; Zaragoza, Spain; Buenos Aires, Argentina; Aqaba, Jordan; and Panama City, Panama. The last forum was held in San Jose, California, in 2018 and has been on hiatus due to the pandemic. 

The overarching theme of the Rosenberg Forum is “reducing conflict in the management of water resources.” Specific sub-themes are chosen by an advisory committee for each individual forum. The primary objective is to facilitate the exchange of information and experience in the management of water resources.

The problems of managing water are surprisingly common around the world. However, approaches and solutions may differ depending on the available financial resources as well as social and cultural norms. Discussions of alternative approaches and identification of what works and what doesn’t are intended to aid in devising more effective and efficient water-management schemes.

2023-03-07T13:21:48-08:00March 7th, 2023|

UC Climate-Ready Landscape Trials Identify Low-Water Yet Attractive Plants

By Saoimanu Sope, UCANR

Good news: roses can be a part of your water-efficient landscape. Lorence Oki, UC Cooperative Extension environmental horticulture specialist in the UC Davis Department of Plant Sciences, identified rose cultivars that remain aesthetically pleasing with little water.

Oki is the principal investigator of the Climate-Ready Landscape Plants project, which may be the largest irrigation trial in the western U.S., and the UC Plant Landscape Irrigation Trials (UCLPIT), the California component of that project. These projects evaluate landscape plants under varying irrigation levels to determine their optimal performance in regions requiring supplemental summer water.

“There are some assumptions that pretty plants use a lot of water, like roses,” Oki said. “Everyone thinks they need a lot of water, but we’ve found some that don’t, and they still look great. A water-efficient landscape doesn’t need to look like a Central Valley oak-grassland in the summer. It can look really attractive.”

In 2021, Oki’s team at UC Davis identified Lomandra confertifolia ssp. pallida “Pom Pom” Shorty and Rosa “Sprogreatpink” Brick House® Pink as two of the best low-water plants in the trial.

“The useful tip or information that is shared at the end of each trial is the selection and designation of plants as Blue Ribbon winners. These are the plants that looked good with an overall rating of 4 or higher throughout and were on the low (20%) water treatment,” said Natalie Levy, associate specialist for water resources, who manages the project at the UC ANR South Coast Research and Extension Center.

How plants earn a blue ribbon

Each trial year, the selection of new plants is based on research recommendations and donated submissions from the nursery industry. The landscape plants are trialed in full sun or 50% shade cover.

Irrigation treatments are based on the rate of evaporation and plant transpiration (evapotranspiration) measured through a local California Irrigation Management Information System (CIMIS) weather station that provides a reference evapotranspiration (ETo) rate.

Three levels of irrigation are provided to the plants equal to 20%, 50%, and 80% of ETo. The volume of water applied is the same at each irrigation based on soil characteristics, but the interval between applications varies with weather and the treatment. Using this method, irrigations for the 20% treatment are less frequent than the 80% treatment.

“The 20% treatment during the 2022 trial was irrigated an average of once per month while the 80% treatment was irrigated weekly,” explained Levy.

During the deficit irrigation trial, monthly height and width measurements are taken to determine the plant growth index. Monthly qualitative aesthetic ratings on a scale of 1 to 5 are determined for foliage appearance, flowering abundance, pest tolerance, disease resistance, vigor and overall appearance.

A second round of flowering abundance and overall appearance measurements are also taken to capture more of the blooming period. For example, UCLPIT identified in the 2020 trial at South Coast REC that the “Apricot Drift” rose had a mean overall appearance score of 3.5 out of 5, deeming it “acceptable to very nice” and a low water use plant within the Water Use Classification of Landscape Species or WUCOLS guide.

Project expands options for landscape planting

While attending UC Davis as a master’s student, Karrie Reid, retired UCCE environmental horticulture advisor for San Joaquin County, assisted Oki with landscape water conservation research. The landscape plant irrigation assessments were initiated at UC Davis in 2004 and the UCLPIT project, now in its 20th year, originated from her master’s thesis project from 2005 to 2007. A CDFA grant supported duplicating these fields at the South Coast REC in 2017.

“(WUCOLS) only has 3,500 plants in it. There are guesses that there are close to 10,000 cultivars in urban landscapes in California, if not more,” said Oki. “WUCOLS also didn’t have numerical ratings. Instead, you’ll see verbal ratings like ‘low water use’ or ‘high water use.'”

The UCLPIT project has not only developed numerical recommendations for irrigation, but it has also added new landscape plants that are compliant with California’s Model Water Efficient Landscape Ordinance. In fact, UCLPIT’s data is one of the few sources that can be used to supplement WUCOLS.

Geographic diversity of trial sites adds to knowledge base

In addition to UC Davis and South Coast REC in Irvine, the trials have expanded beyond California as the Climate-Ready Landscape Plants project and is in progress at Oregon State University, University of Washington, University of Arizona and Utah State University thanks to a USDA/CDFA grant awarded in 2020.

Lloyd Nackley, associate professor of nursery production and greenhouse management at Oregon State University, is the principal investigator of the trial in the Portland metro area, which is entering its third year.

“People know that there are drought tolerant plants, but there are many. We’re trying to highlight lesser known or newer varieties. And even though the trial is three years, most gardeners would hope that their garden lasts longer than that,” said Nackley.

One of the observations that Nackley recalls is of the Hibiscus Purple Pillar plant. Unlike the trial at South Coast, the Purple Pillar did not perform well in Oregon in the spring.

“It wasn’t until August that we saw the plant bloom and begin to look like what we saw from South Coast in April,” Nackley said.

Ursula Schuch, horticulture professor and principal investigator of the trial taking place at the University of Arizona, was also surprised at the range of performance among different plant types and the effects of irrigation, heat and temperature.

“This research will reassure green industry professionals that they can stretch their water budget to successfully cultivate more plants, watering them according to their needs instead of irrigating every plant according to the highest water-using plants,” said Schuch.

Although research is only conducted in the West, the hope is that there will be trials in other regions of U.S.

Doing so would yield comprehensive information about the plants and their performance in different climates. As extreme weather events persist in the U.S., disease pressure and risks do too. Trials throughout the country would provide location-specific data regarding disease susceptibility.

To learn more about the UCLPIT research project, visit https://ucanr.edu/sites/UCLPIT/

 

2023-01-17T14:19:57-08:00January 17th, 2023|
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