Why We Need Tree Canopies | Part II

Welcome to Part II of "Why We Need Tree Canopies". This portion will go into a bit more depth of CA's current tree situation, benefits of living near green space and what other jurisdictions in the country are doing to mitigate tree loss and increase benefits from expanded tree canopies.

According to a study by the Carnegie Institution for Science, well over 50 million trees throughout California are at risk of dying because of the drought. Furthermore, drought allows bark beetles to thrive, creating more dire conditions for susceptible trees and, as of last spring, the U.S. Forest Services estimated 12 million trees have already died from a mix of both severe drought conditions and this resulting bark beetle infestation. Studies show that the vast majority of the areas affected have been in the San Joaquin Valley and surrounding Central Valley. Governor Brown declared a state of emergency over dying trees and the California Department of Forestry and Fire Protection (CAL FIRE) have focused efforts to remove dead trees in the SJV to eliminate the area’s vulnerability for fire and wildfire outbreaks.

Tree loss and disease from drought.

Tree loss results in increased forest fire susceptibility and severity as well as decreased animal and insect diversity, water resources and carbon sequestration. This imminent increase in fires, dying trees and beetle infestations will only continue to produce more carbon emissions, contributing to poorer air quality and climate change.

While the drought has exacerbated these conditions, an increased population of well-maintained, native and drought-tolerant trees will help mitigate some of these issues and provide substantial benefits to communities that plant these types of trees, increasing the local urban canopy. The USDA’s report Effects of Drought on Forests and Rangelands in the U.S.: A Comprehensive Science Synthesis notes that while native, drought-resistant plants do require some water and will increase a community’s necessary allotment, forests, including urban forests, are naturally resilient and resist effects from drought. Forests also help manage erosion and water runoff, supply and quality.

The San Joaquin Valley is home to many who both suffer greatly from asthma and live in poverty. Tree canopies, as previously mentioned, improve local air quality through CO₂ sequestration, reducing respiratory-related illnesses and deaths. Tree canopies also provide widespread cooling and temperature control. Tree Fresno, a local environmental agency, shares the information that open, cemented areas can be over five degrees Fahrenheit warmer than similar areas with green space. This causes a reduced quality of life. Community members are less able to take advantage of outdoor amenities, exercising or interacting outdoors; people are more likely to suffer from health problems because of high air-pollution levels and daytime temperatures as well as minimized nighttime cooling; energy bills are higher due to a great need for air conditioning; and city resources become more limited.

Tree Fresno is the "regional resource for trees, trail and greenbelts".

To combat these severe results, Tree Fresno has also shown that a single fully-grown tree can have a net cooling effect of 10 single-room air conditioners each running for 20 hours a day and that shade reduces UVB radiation exposure by up to 50 percent. Pacific Gas and Electric Company (PG&E) shares an emissions factor of 457 pounds CO₂ per MWh. This means that 10 500 Watt air conditioning units running for 20 hours a day is 100 kWh, which is about 45.7 pounds of kWh-related CO₂ avoided with every tree planted.

By providing temperature control, the surrounding community is more willing and able to take advantage of outdoor activities and services and less likely to suffer from heat exhaustion and other related illnesses. Health benefits do not stop here. Environmental Health Perspectives recently published a Harvard University study illustrating a link between lower mortality rates as a result from respiratory illnesses and cancer and living near greenery. Living near greenery decreases air pollution and allows for more physical activity and social engagement. The study also found a much lower prevalence of depression in those that lived near greenery.

Additionally, trees reduce road maintenance costs. The Journal of Aboriculture shared a field study conducted in Modesto, CA, which showed that an unshaded street required 6 slurry seals over a period of 30 years and a tree-shaded street only required 2.5 seals over the same time period. This is a 58 percent reduction. So, let us consider the City of Clovis, which has over 120 Million square feet of roads. If the cost for slurry seals are approximately $0.66 per square foot, the City could see potential savings of nearly $80,000,000. Moreover, in its 2014 Regional Transportation Plan, Fresno COG indicated that over $1 Billion needed to be put towards road operations and maintenance projects. Projects may be avoided or have reduced costs with an increase in tree-lined streets.

I also must point out that since the San Joaquin Valley suffers from high unemployment and poverty levels, we need to shed light on the extensive economic benefits provided by expanded and properly maintained tree canopies. Trees provide natural and low-cost energy efficiency benefits to homes and properties protected and shaded by them. Properly placed trees can reduce cooling costs by 30 percent and can even lower heating costs by up to 50 percent. Lower utility bills put more money back into the pockets of the community, which then goes back into the local economy. Tree-lined streets also promote a higher level of business activity and increase home and property values.

Louisville suburb south of Bowman Field

Louisville, Kentucky adopted a Tree Canopy Ordinance and has since formed a nonprofit organization dedicated to expanding the City’s tree canopy. In support of this effort, the City released a study that outlined many of these benefits in detail. As of 2015, Louisville’s canopy covered about 37 percent of the City, which equates to approximately 147 square miles with nearly 6.2 million trees. This canopy provides the community with over 67 million kilowatt hours (kWh) and over $5 million in energy savings each year as well as a $240 million increase in property values citywide. Additional savings have been reported from nearly 7 million pounds of pollutants and 400,000 tons of CO₂ removed from the atmosphere each year and a near 19 billion gallon reduction in storm water runoff each year. The City of Louisville estimates that $330 million in savings will be seen annually from just maintaining the current tree canopy. Expanding the canopy will only increase these savings across all sectors.

Are you impressed by these benefits of tree canopies? Would you like your city to adopt a Tree Canopy Ordinance? Let us know!

USGBC Central California: Resilient Lanscaping

Why We Need Tree Canopies | Part I

The San Joaquin Valley suffers from urban heat island (UHI) affect; pavement and other dark-colored surfaces throughout the Valley absorb sunlight, trapping heat and increasing local temperatures. This adversely affects local air quality as well as energy efficiency capabilities, energy consumption, public health, climate resilience, and quality of life, among other measures. Furthermore, the SJV not only generates its own pollutant emissions, but is also impacted by transport of pollutants around the Valley and from the Bay Area. Although air quality in the region is slowly improving, SJV Counties still have not met federal ambient air quality standards for pollutants such as PM_2.5 and PM₁₀ as well as 8-hour ozone.

This is an ideal canopy, no?

There is no better (and cheaper!) solution to both increasing energy efficiency and reducing greenhouse gas (GHG) emissions than protecting and expanding our existing tree canopies and developing additional canopies. In addition, trees provide extensive water, economic and crime reduction benefits to urban areas.

Native, drought-tolerant trees will not only thrive in our region, but also contribute to necessary air quality improvement and widespread cooling, especially in summer months. Tree canopies sequester CO₂, reducing the amount of greenhouse gases in the atmosphere. They are natural air conditioners, shading and cooling both buildings and streets and reducing summer temperatures of and, therefore, cooling costs for the entire tree-lined neighborhood or community. Trees also provide windbreak, reducing heating costs, and absorb sounds, greatly reducing noise pollution.

Greater the canopy, greater the benefits.

Additionally, streets and medians lined with trees require significantly less watering than those with grass. Trees help capture rainfall and recharge aquifers through filtering water through their roots. This also contributes to reduced storm water runoff, decreasing potential flooding, storm water management costs and flow of polluted water.

Drought conditions shouldn't stop the planting of trees. A lack of tree canopy will not only negatively contribute to issues such as poor air and water quality, but the continued loss of trees due to forest fire, bark beetle infestations and bacterial infections, such as fireblight, will worsen these effects on the local communities.

There is a clear need for mitigation policies. Increasing tree growth in parks and making use of open non-green space, such as medians, public streets and plazas, by expanding tree canopies and creating a landscape in which jurisdictions understand how and why urban canopies are so important and beneficial will improve energy efficiency, local temperature and air quality, minimizing adverse effects of greenhouse gas emissions and urban heat island effect.

Do you like the sound of this? Stick around for Part II where I will describe benefits in greater detail!

Agriculture Water Use, Consumer Practices and the Drought

California is still in a drought. Surprised? You shouldn't be; this has been all over the news for months now. The lack of ground and other water sources is concerning, and so even though Samantha and I have both written about behavior modification and the megadrought future of California, there is more to be said about what you can do and what others, especially those in agriculture, should be doing to mitigate the dry conditions in the state.

Governor Brown has cracked down on water allotments, reducing potable urban water usage by 25%. Final decisions about agricultural water use have yet to be determined. About 80% of water consumed in the state of California goes to agriculture and the state's farmers need all that water because they supply much of the country’s produce, yet the industry has already seen cutbacks on surface water allotments and will likely see more.

Some farmers in the Sacramento and San Joaquin river delta have said they will voluntarily give up 25% of their allotments if the government does not ask for additional cutbacks. This is huge because water rights in this region date back a couple of centuries and are fiercely protected.

Photo Source: econlife

The state may have a decision on the agricultural water cuts soon, but how significant the cuts will be is not known. Even though there are many farmers who have said they would take a voluntary cut, there is no way to know how many actually will and who will wait to reduce their usage when final decisions and programs are developed. Many hope that the farmers who are volunteering water cuts will inspire others to follow suit before final decisions are made.

Farmers may need to rethink their crops as well. Some crops are so water intensive that it will not make sense to grow them as the drought conditions perpetuate. One such crop is alfalfa – the reason why an excessive amount of water is needed to produce a burger. Plus, a lot of our alfalfa crops are sent to China for cattle feed, so American consumers cannot even reap the benefits!

Photo Source: Daily Kos

As a consumer, you, too, can choose to buy and eat less water intensive produce. I stopped drinking Almond milk when I learned it takes about a gallon of water to produce each almond. That is quite a guzzler! And almonds aren't even the biggest guzzler in the nut family; walnuts are far worse!

How can you figure out how much water your food takes to produce? Check out this handy interactive infographic by the New York Times and prepare yourself to be shocked. Try participating in Meatless Monday. Try millet instead of rice. We can all make a difference to mitigate the effects of the drought whether or not we live in California. When will you start?

Megadroughts: Our Future

Usually Seattle has cloudy skies and constant drizzle between mid October and late June and, to be honest, I was not looking forward to leaving Southern California for this weather. This winter, however, has been so mild. We’ve had as few as none and no more than four rainy days a week, which in comparison to just last year is nothing. The sun is shining now and it reached nearly 70 degrees just a couple of days ago. We're supposed to be smack dab in the middle of our very long rainy season! Clearly, the climate is changing. Not only are we Seattleites not getting a whole lot of rain or snowfall, but Californians have also received so little that there is approximately one year of water left. ONE year. That’s it.

A NASA water scientist calculated that all reservoir water, groundwater and backup supply water for the state of California will only last through the next year. Last winter, there

Photo Source: dpw.lacounty.gov

was a drastic decrease in rain and snowfall and this year, there has been even less.

Unfortunately, there hasn’t been enough urgency surrounding this issue. There have been a few local water restriction efforts set up throughout the state, but the golf courses in Palm Springs continue to be lush and green and not enough Los Angeles residents are participating in the Cash for Grass Rebate Program to alter their lawns. There hasn’t been a huge drive to create or enforce a statewide water conservation campaign.

To top it off, NASA predicts “megadroughts” to take over the Southwest and Great Plains starting sometime during the second half of this century. Each megadrought can last between 10 years and a few decades. So if you notice that our current water crisis is making it harder for Californians to live, farm, raise cattle, etc., just wait. This year, areas all over the state have had increased problems with water theft, farmers in the San Joaquin Valley are fallowing an increased number of plots and reservoirs are at record lows. I hate being a Debbie Downer, but this is our future. 

Photo Source: wakefieldbiochar.com

Most Californians, instead of creating a strategy to deal with this situation, just stare at the sky, hoping for a few drops of rain. Hoping won’t cut it at this point. The public needs to be involved in and prepared to substantially reduce water consumption and dependency, even more so than they have. Laws need to be implemented that will combat these issues with groundwater sustainability plans, enforced water use limitations and efficient technology innovations. Think we can do it? I do. But we need to act. The longer we wait, the less likely change and improvements will not only happen but be effective.


Update: Governor Brown and California lawmakers develop strategies for drought mitigation. And as of April 1st, water restrictions have been imposed, calling for 25% reduction on California's supply agencies. That's what I call progress!