Posting every Friday at noon is how I act in solidarity with young climate strikers all over the world who want their elders to save their future.

The U.S. Environmental Protection Agency (EPA) is warning us that our over-heated cities are only going to get hotter as the climate changes. Cities are “heat islands” due to all those crammed-together roofs and endless pavement. There are many solutions to this problem being implemented, haltingly, but let’s concentrate on trees.

All over the world cities are committing to replant the trees they uprooted to plant their city.  Jesus helps us!

Of all the many benefits trees offer a city, the impact on climate change is probably the greatest.

• Properly placed street trees shade the sidewalk which can result in a reduction of 20°F in sidewalk temperature. Unshaded sidewalks store a lot of heat and then radiate it to everything around them, including the people walking on them.
• Street trees transpire, meaning that they give off water vapor through evaporation of moisture from their leaves (like those misting fans in Las Vegas). Evapotranspiration from trees can reduce the temperature around the trees by 2°- 9°. This compounds the cooling effect of shading. Each 10% increase in tree coverage in an urban context can reduce mid-day temp by 1.8°.
• Trees are the walk appeal superfood. The combined effect of shading the sidewalk, shading the humans, and evapotranspiration can transform a walk in hot weather from something 10% of the people can tolerate to something 90% can tolerate. Some say one young, healthy street tree equals the cooling power of 10 room-size air conditioners running 20 hours/day. Street trees have close to 16 times the cooling effect on the human environment as trees in a forest. More walking to daily needs means less driving, which means less combustion heat from car engines adding to the heat island.
• More severe heat raises the cooling load on buildings because the air around them is hotter. Air conditioning operates by expelling indoor heat to the outdoors. As a result, the urban heat island gets hotter and requires more indoor cooling. The first step in unwrapping this vicious spiral is more street trees. They can cool things down enough to restart virtuous cycles.

• Trees are atmospheric carbon reduction champions. They continually inhale carbon dioxide and exhale oxygen, while humans and other animals do the opposite. They also sequester carbon within the tree as the tree grows. Plant enough trees, and they will actually absorb all carbon emitted by humans today. We need a LOT more trees to do that! Unfortunately, humans are going the wrong direction by deforesting places around the world for more cattle farming, among many other reasons. Planting street trees is part of reversing that direction. If there are 4 million miles of streets and roads in the US today (not counting Interstates) and street trees were planted 25 feet on center on either side of all of them, that would total almost 1.7 billion trees. That’s not all the trees the world needs, but every tree planted is a hopeful step in the right direction.

I did not give you all the references for the claims above. They are likely debatable in one form or another, like most science about the moving target of climate change. But our common sense tells us the city is hotter than the countryside and neighborhoods with trees are cooler.

Philly Tree People

Because Philly needs to be the greenest city in the U.S. (another reason to beat Tampa!), our climate change contribution this month is going to the Philly Tree People.

I was looking around for a local group with whom I could connect since I have already discovered major players statewide and nationwide. I lived in leafy West Philly and now overlook the sea of trees in Fairmount Park – those places make a difference. But I happened upon people pushing into the miles of relatively treeless areas in 19125 and 19134: The Philly Tree People. I wrote them and Jacelyn Blank, the co-founder, wrote me back! Then I wanted to talk and she answered the phone!

The letter I received said, “Philly Tree People (PTP) is a neighborhood- based environmental stewardship non-profit organization that focuses on engaging and educating the community in tree planting, tree care and maintenance, and growing the urban forest in the 19125 and 19134 zip codes of Philadelphia, PA. PTP works in conjunction with the Pennsylvania Horticultural Society (PHS) and the Philadelphia Parks and Recreations Department (PP&R) on behalf of property owners to receive free street trees through the state subsidized Tree Vitalize program. We also educate, train and empower residents as they plant and care for trees, improving the neighborhoods in which they live, learn, work and play. PTP is a volunteer-based organization that subsists solely on the generous donations of individuals, a handful of donors, and a few companies.”

Jacelyn and two other women met each other at the neighborhood association and then the Pennsylvania Horticultural Society and ended up starting their own tree-planting squad fourteen years ago — and they are still at it! Only now they have 1000 people on their volunteer list. They continue to work with people who have been volunteering with them for years!

The first time they put shovel to sidewalk they planted 50 trees. Now they not only keep putting trees in the ground, they are involved in Parks and Rec’s 10 year plan for greening the city. That plan is undoing the fact that rich people are more shaded, the poor and Black/brown are less. They want to hire youth and teach them green economy skills and are involved in plantings at schools. One middle school student who got involved years ago now brings her daughter to plant.

Before they got involved, the Parks and Rec wanted to plant more trees but did not have the money. The Pennsylvania Horticultural Society made an alliance so the system could get grants. The way I understand the process, a homeowner or business makes a request for a free street tree. The request goes to Parks and Rec which makes a site visit (since we have planted some ill-suited trees in the past and we need a strategy).Then the request goes to PHS which parcels it out to one of the growing number of neighborhood groups who are the main boots on the ground. (Use the comments section for corrections, anyone!) In Fishtown, you dust off your hands after planting day is over and head down to the Phila Brewing Co. for a luncheon (sponsored for 14 years, as well!!). Its all about being neighbors, face to face.

Here are some final facts from their informative letter:

• Their largest community events are tree plantings. To date they’ve helped plant over 2000 trees. A few weeks ago they planted 46 street trees, and have submitted 43 more street tree applications with PHS which will be planted in April 2022.
• In addition to plantings, they run a tree Pruning Club which maintains and beautifies the tree cover. They’ve helped to prune over 500 trees so far.
• They have partnered with other organizations in their zip codes, including “friends of” park groups and local schools to to help them build and grow their green spaces, including teaching people how to plant and tend trees.
• Their newest program is the PTP Green Corps, an environmental stewardship program for local youth. They help youth develop green job skills, learn about arboriculture, and heighten their awareness of environmental issues impacting the neighborhoods and the planet.

The Philly Tree People are working on a shoestring but it looks like the more money they have, the more good they will do. Efforts like:

• build and maintain their tool library
• buy branded swag as gifts for volunteers
• buy meals for tree planters
• pay for discounted mulching services at pruning club events
• secure supplies for Green Corps
• fund administrative costs
• procure a new storage location and operations hub to stage their plantings
• grow their programs and “branch out” (pun intended) to make a greater impact

Thanks Philly Tree People Board! Consistent, long-term, leadership makes all the difference:

• Jacelyn Blank, PTP Co-Founder, ISA Certified Arborist #PD-2783A
• Nykia Perez Kibler, PTP Co-Founder, ISA Certified Arborist #PD-2135A
• Jen Brown, New PTP Board Member
• Eli Gorman, New PTP Board Member
• Kara Kneidl, New PTP Board Member