Posts Tagged: heat

Now is the time to plant climate-ready trees, says UCCE researcher

In a drought-prone region like Southern California, working with Mother Nature is not only wise but necessary, according to Janet Hartin, UC Cooperative Extension horticulture advisor for Los Angeles, San Bernardino and Riverside counties, who studies climate-ready trees.

In 2020, Governor Newsom launched the California Climate Action Corps, empowering Californians to protect their communities from the impacts of climate change. Newsom's call to action emphasizes the need for long-term and sustainable solutions like Hartin's research, which urges Southern California to care for existing trees and plant new ones.

In collaboration with the U.S. Forest Service and other UC Cooperative Extension scientists, Hartin is amid a 20-year research study identifying trees suitable for California's different climate zones. Her work provides a comprehensive understanding of trees and their benefits related to human and environmental health, particularly as Californians navigate climate change's evolving challenges.

One of these concerns is urban heat islands. UHIs are areas in which heat is reradiated from paved concrete or asphalt surfaces. In cities covered in asphalt, like Los Angeles, average temperatures can become six degrees hotter than surrounding areas.

To reduce urban heat islands, she has been working with community organizations to plant trees. In March, for example, Hartin teamed up with the Inland Empire Resource Conservation District to increase tree canopy in the Inland Empire.

“We've collaborated extensively with her over the years, and we knew Janet had been developing a regionally scaled concept for connecting community members to climate-appropriate trees, alongside access to technical assistance from regional UCCE Master Gardeners to ensure long-term tree health and survival,” said IERCD District Manager Mandy Parkes.

Trees keep cities cool

To keep the city cool, some Los Angeles neighborhoods are repainting pavements with reflective coating. According to a 2020 study published in Environmental Research Letters, reflective coating can decrease pavement temperatures up to 10 degrees. As helpful as this is, augmenting urban landscapes to include heat-, drought- and pest-resistant tree species, whether native or not, can significantly reduce the impacts of urban heat islands too.  

“Trees can cool impervious surfaces by 40 to 65 degrees,” Hartin said. During a 2021 study, in May and June Hartin discovered that unshaded asphalt could be more than 60 degrees hotter than shaded asphalt during late spring and early summer in inland and desert cities.

Other than providing shade, trees are effective at deflecting the sun's radiation and cooling the atmosphere through evapotranspiration. Given that they absorb and store carbon as well, trees lessen the impacts of pollution from fossil fuels.

“A well-tended mature landscape tree can absorb 40 tons of carbon over its lifespan,” said Hartin. 

In a 2021 blog post, Hartin suggests trees be selected based on their adaptation to the “micro-climate” in each particular landscape, noting factors to consider like shade, proximity to buildings, space needs below and above ground, soil type and water source. She also recommends the Sunset Western Climate Zone maps for reference, noting that they are “more precise than USDA zones for our warmer climates.”

Based on the study with the U.S. Forest Service examining the performance of 12 species of underplanted but promising landscape trees at UC Riverside, favorable candidates include bubba desert willow and maverick thornless honey mesquite for their drought resistance, and red push pistache for its drought and heat resistance. 

Tamara Hedges, executive director of UC Riverside Palm Desert Center and member of the Board of Directors for the Oswit Land Trust, agrees that trees are important in our fight against climate change: 

“Through our partnerships with the UC California Naturalist and the Master Gardener Programs and many other nonprofits in the Coachella Valley, natural ecosystems are being protected and expanded and built environments cooled through the planting of appropriate tree species. These UC/USFS studies go a long way in identifying new underrepresented tree species."  

General tips for planting

For California, planting in early fall through late winter provides ample time for trees to establish a strong root system  before enduring the summer heat. Doing so also means that natural rainfall can fulfill water needs, as opposed to solely relying on irrigation systems.

Unlike newly planted trees, mature trees should be watered infrequently but deeply. Watering too often can reduce the level of oxygen in the rootzone and result in waterlogged soils prone to crown and root rots. 

During the fall, trees only need about 15% of the water they would require in the summer. When watering, keep the tree trunk dry. Because the roots of the tree grow outward and are usually a foot deep into the ground, Hartin recommends watering the area around the trunk rather than the trunk itself. This will also help avoid water waste.

“Trees not adapted to the climate they're planted in and not receiving proper care are much more susceptible to invasive pests like shothole borers and diseases,” said Hartin. “Even the loss of one front yard tree can significantly reduce shade, increase the surrounding temperature, and diminish energy savings.”

 

Disaster resources available to prepare for heat, wildfire, power outages, quakes

September is National Preparedness Month, designated to encourage disaster and emergency readiness. To help Californians prepare for extreme heat, earthquakes, public safety power shutoffs and wildfire, University of California Cooperative Extension has created a disaster preparedness website organized for quick access to critical information.

The website https://ucanr.edu/Disaster contains fact sheets with tips for getting prepared.

“Unfortunately, with a warming climate, we are facing more and more extreme climate-related events such as heat waves, wildfires, power shutoffs and storms. All Californians need to step up their preparedness efforts to be ready to meet this more uncertain future,” said Susan Kocher, UC Cooperative Extension forestry advisor, who co-authored the disaster preparedness resources for the website.

Extreme heat

The fact sheet for extreme heat events offers suggestions for avoiding heat exposure, such as identifying nearby cooling centers and covering windows to keep heat out. It also suggests things to do during hot weather such as staying hydrated, taking cool showers and keeping pets indoors. It describes symptoms of heat-related illnesses, which can have serious health effects.

Public Safety Power Shutoff

During extreme weather events, electrical power in high fire-threat areas may be shut off to prevent sparking. This precaution is known as a Public Safety Power Shutoff. A PSPS is most likely to occur from May to November, when conditions are the hottest and driest.

UC Cooperative Extension recommends signing up to receive PSPS alerts from your energy company. Experts also advise making a plan for medications that need to be refrigerated or medical devices that require power. To prevent foodborne illness, they offer suggestions for ensuring food safety during and after a power outage.

Wildfire and smoke

Wildfire smoke can harm your health. During wildfires, UC Cooperative Extension recommends wearing an N95 outdoors to reduce smoke exposure and taking steps to prevent smoke from entering buildings. To reduce wildfire risk, the website describes methods of removing flammable vegetation around homes.

Earthquakes

UC Cooperative Extension offers safety tips for before, during and after an earthquake. Identifying the safest place in your home during an earthquake in advance is helpful. For example, doorways are not the safest place to be in modern homes. Experts recommend crawling under a sturdy desk or table, while avoiding areas next to windows, beneath ceiling fixtures or near large items that may fall during an earthquake.

The website also offers resources on drought, food safety after a fire, and wildfire preparedness and recovery.

In 2020 and 2021, Cooperative Extension researchers from around the country held listening sessions with community members who had experienced extreme weather events and other types of disasters to learn what had worked well, what had not, and how communities could be strengthened. 

In response, these disaster resources were developed by Kocher, UC Davis undergraduate student Caydee Schweitzer, Tracy Schohr, UC Cooperative Extension livestock and natural resource advisor, and Vikram Koundinya, UC Cooperative Extension evaluation specialist. The group plans to add fact sheets on more disaster topics in the future.

This project was funded by a USDA National Institute of Food and Agriculture Renewable Resources Extension Act grant.

MEDIA CONTACT: Susan Kocher, UC Cooperative Extension forestry advisor, sdkocher@ucanr.edu

Can vines speed urban cooling?

Study explores cooling benefits of fast-growing vines as trees take their time

Summer safety: Tips to avoid foodborne and heat illnesses

Happy summer! It's time to get the barbecue grilling and the pool party started. To keep your summer healthy and fun, UC ANR offers some important safety tips.

Food safety

Food poisoning is a serious health threat in the United States, especially during the hot summer months. According to the Centers for Disease Control and Prevention (CDC), 1 in 6 Americans suffer from a foodborne illness each year, resulting in thousands of hospitalizations and 3,000 deaths. 

Both the CDC and U.S. Department of Agriculture (USDA) suggest four key rules to follow to stay food safe:

• Clean: Clean kitchen surfaces, utensils, and hands with soap and water while preparing food. Wash fresh fruits and vegetables thoroughly under running water.
• Separate: Separate raw meats from other foods by using different cutting boards. And be sure to keep raw meat, poultry, seafood and eggs away from other items in your refrigerator.
• Cook: Cook foods to the right temperature; be sure to check internal temperature by using a food thermometer.
• Chill: Chill raw and prepared foods promptly.

Here are some additional tips from the USDA. Be sure to check out the CDC's comprehensive food safety website, which also has materials in both Spanish and English. For food safety tips in real time, follow USDA Food Safety on Twitter.

Summer also means more outside grilling, which can pose unique food safety concerns. Before firing up the barbecue, check out these five easy tips from UC Davis.

Before you take off on a road trip, camping adventure or boating excursion, don't forget to consider food safety. You'll need to plan ahead and invest in a good cooler.

Remember, warns the USDA, don't let food sit out for more than one hour in temperatures above 90 degrees F. And discard any food left out more than two hours; after only one hour in temperatures above 90 degrees F.

If there are any doubts about how long the food was out, it is best to throw it out!

Get more food safety tips for traveling from the USDA.

Avoid heat illness

“Summer can be a time for fun and relaxation, but in warm climates, we need to stay aware of the signs of heat illness and help keep our family members and co-workers safe,” says Brian Oatman, director of Risk & Safety Services at UC ANR.

“UC ANR provides comprehensive resources on our website, but it's designed around California requirements for workplace safety.” But, Oatman notes, much of the information applies.

“The training and basic guidance – drink water, take a rest when you are feeling any symptoms and having a shaded area available – are useful for anyone at any time.”

To increase your awareness of heat illness symptoms – and to learn more about prevention – Oatman suggests a few resources.

“Our Heat Illness Prevention page has many resources, including links for training, heat illness prevention plans, and links to other sites. One of the external sites for heat illness that I recommend is the Cal/OSHA site, which spells out the basic requirements for heat illness prevention in the workplace. It's also available in Spanish." 

For those on the go, Oatman also recommends the National Institute for Occupational Safety and Health (NIOSH) mobile heat safety app.

 

Summer safety tips

Happy Fourth of July! It's time to get the barbecue grilling and the pool party started. To keep your summer healthy and fun, UC ANR offers some important safety tips.

Food safety

Food poisoning is a serious health threat in the United States, especially during the hot summer months. According to the Centers for Disease Control and Prevention (CDC), 1 in 6 Americans suffer from a foodborne illness each year, resulting in thousands of hospitalizations and 3,000 deaths. 

Both the CDC and USDA suggest four key rules to follow to keep food safe:

• Clean: Clean kitchen surfaces, utensils, and hands with soap and water while preparing food. Wash fresh fruits and vegetables thoroughly under running water.
• Separate: Separate raw meats from other foods by using different cutting boards. And be sure to keep raw meat, poultry, seafood and eggs away from other items in your refrigerator.
• Cook: Cook foods to the right temperature; be sure to check internal temperature by using a food thermometer.
• Chill: Chill raw and prepared foods promptly.

Here are some additional tips from the USDA. Be sure to check out the CDC's comprehensive food safety website, which also has materials in both Spanish and English. For food safety tips in real time, follow USDA Food Safety on Twitter.

Summer also means more outside grilling, which can pose unique food safety concerns. Before firing up the barbeque, check out these five easy tips from UC Davis.

Handling food safety on the road 

Before you take off on a road trip, camping adventure or boating excursion, don't forget to consider food safety. You'll need to plan ahead and invest in a good cooler.

Remember, warns the USDA, don't let food sit out for more than 1 hour in temperatures above 90 degrees F. And discard any food left out more than 2 hours; after only 1 hour in temperatures above 90 degrees F.

If there are any doubts about how long the food was out, it is best to throw it out!

Be sure to bring plenty of water, too, to stay well-hydrated.

Get more food safety tips for traveling from the USDA.

 

Avoid heat illness

“Summer can be a time for fun and relaxation, but in warm climates, we need to stay aware of the signs of heat illness and help keep our family members and co-workers safe,” says Brian Oatman, Director of Risk & Safety Services at UC ANR.

“UC ANR provides comprehensive resources on our website, but it's designed around California requirements for workplace safety.” But, Oatman notes, much of the information applies.

The training and basic guidance – drink water, take a rest when you are feeling any symptoms and having a shaded area available – are useful for anyone at any time.

To increase your awareness of heat illness symptoms – and to learn more about prevention – Oatman suggests a few resources.

“Our Heat Illness Prevention page has many resources, including links for training, heat illness prevention plans, and links to other sites. One of the external sites for heat illness that I recommend is the Cal/OSHA site, which spells out the basic requirements for heat illness prevention in the workplace. It's also available in Spanish." 

For those on the go, Oatman also suggests the National Institute for Occupational Safety and Health (NIOSH) mobile heat safety app.

Have a great (and safe) summer! 

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