Right Tree, Right Place

Trees are often pointed to as a panacea for climate change, the most cost-effective environmental engineering we can do to cool the planet. The t-shirt slogan/ ancient Chinese proverb is inescapable: "The best time to plant a tree was 20 years ago. The second best time is now." However, my time following grasslands scientists on Twitter, back when it was a useful tool for networking and research, made me look more skeptically at trees. See my blog post from 2019 with more links about the relative importance of grasslands and kelp forests as carbon sinks. I still chuckle at the quip by one scientist: "Trees are dorks who put loads of their carbon aboveground." 

Mount Diablo sunset, photo credit: me

Besides being prone to burning and unhelpfully releasing lots of carbon dioxide into the atmosphere, trees can be a problem because you can't just plant any tree anywhere, and people don't always take the time to think ahead. A July 2025 Guardian UK article "How a £1.5bn ‘wildlife-boosting’ bypass became an environmental disaster" describes just such an instance, where a biodiversity corridor along an English highway instead turned into a dead zone, where nearly all the tree saplings died: "they had planted the wrong species in the wrong place." National Highways, the supervising agency, had to admit nature was left worse-off after the project, with the death of nearly all of the 860,000 trees they planted.

Meanwhile, I spent most of the last five years working on wildfire mitigation in California, where the slogan "right tree, right place" is repeated by all the players (government, utilities). In particular, the utilities want you to think ahead before planting a tree: sometimes they get left holding the bag when someone's poorly placed or poorly maintained tree comes into contact with bare wire and there's an ignition. All three major investor-owned electrical utilities in California have repositories of information on how to select the right tree and place it at a safe distance from electrical infrastructure.

 

Seen in a friend's garden, photo credit: me

Here are some tree planting planning resources the utilities point to:

• CalPoly's SelecTree Tool (which includes a filter for California native plants and "has fall color")
• The Arbor Day Foundation's Tree Wizard Tool

And then there are the utility-specific pages:

• PG&E "Planting Safely" (scroll down to Safe Planting Resources)
• SCE "Power Lines and Trees" (and the two-page 2019 brochure "Right Tree, Right Place") 
• SDG&E "Plant the right tree in the right place"

Some other resources you might want to reference:

• The California Native Plant Society's Calscape Search Page - to locate native trees and shrubs to suit your needs
• The National Cooperative Soil Survey's Web Soil Survey - to learn about your soil's characteristics

On a related note, researchers published a study in Nature Communications last year (2024) looking at where global warming from reducing surface reflectivity (albedo) from increasing tree canopy can partially or even completely counteract the cooling benefit of increased carbon storage in trees. It turns out "[i]n most locations, these changes in albedo offset or even negate the carbon removal benefits" (Hasler et al. 2024 "Accounting for albedo change to identify climate-positive tree cover restoration").

The researchers produced a spatial data set for land managers to help them determine how much the decreased reflectivity from additional tree cover might impact the carbon removal benefit of a reforestation project. Without taking the reflectivity reduction impact into account, land managers might be overestimating the carbon removal benefit of reforestation projects "anywhere from 20 to 81%" (as described in the Nature Conservancy summary of the study "New maps help decision-makers factor albedo into tree-planting strategies").

If you don't have an easy way to use a spatial data set, you can estimate a reforestation project's impact using the Nature Conservancy's Naturebase mapping tool, which "integrates albedo into both its reforestation and avoided forest conversion estimates."

My backyard Bradford Pear tree, photo credit: me

Remember - trees are dorks! They burn and they absorb sunlight which both warm the planet. Plant them strategically! 

Grasslands, Kelp > Trees: my parking lot of helpful threads and papers

I've now twice had to go rummaging around on Twitter for these helpful threads and links to help me back up a claim that trees are not a good global panacea for climate change. Today yet another person in my friend circle saw a scary climate change article (in her case right after reading about how mass genocide of Native peoples led to afforestation and global cooling in the 15-16th c.) and responded with "plant trees!" So I had to go spam her with links. And then realized, oh, this seems to be a recurring event.

Welcome to my parking lot of helpful threads and papers to support the idea that grasslands and other non-tree carbon sinks like kelp forests are better than trees for slowing climate change.

Native grassland/prairie restoration project by CAFNR, U Missouri (CC BY-NC 2.0) 

~A paper out of UC Davis last year:

Grasslands More Reliable Carbon Sink Than Trees: In Wildfire-Prone California, Grasslands a Less Vulnerable Carbon Offset Than Forests - Article by Kat Kerlin (July 9, 2018, UC Davis), describing the findings published in this paper:

Grasslands may be more reliable carbon sinks than forests in California (2018) by Pawlok Dass (UC Davis) et al. Environmental Research Letters. 

- And it doesn't appear to be behind a paywall! 

~December 2018 Twitter threads by crop scientist Dr. Sarah Taber:

Dec. 10, 2018: Responding to a question about the carbon footprint of pasture-raised burgers, and then going on a wonderful GIF-rich rant about the cultural biases behind tree-centric climate change/land management research and policy. Excerpt:

The other thing is that "How much carbon can we lock up in trees?" is a lot better researched than "How much carbon can we lock up in grasslands?"

Because northwest European land management is more about forests than grasslands, so that's where rich countries' grant $ goes.

Dec. 11, 2018: Thread about "blue carbon" and the potential of kelp forests to act as carbon sinks. Excerpt:

Most importantly- unlike trees that can burn in wildfires or grasslands that can be plowed up, carbon locked in the deep ocean is not prone to any known human or natural interference. It's the most secure place we know of to sequester carbon.

~Around the same time, on Dec. 9, 2018, a grassland scientist Tweeting as Pastures Politic responded to someone posting "Spoiler alert: it's trees," referring to the Scientific American article "The Best Technology for Fighting Climate Change Isn't a Technology" (Dec. 5, 2018), with "NOPE. It's grasslands. Trees are dorks who put loads of their carbon aboveground." Here's the helpful thread supporting that nope.

After the "trees are dorks" comment, my favorite quote in that thread, by a plant scientist I follow on Twitter, posting as Itati Vasquez Chavez Santamaria:

Savannas and grasslands are basically underground forests which regenerate their top layer content due to fire and grazing. 

(See original Tweet)

~I first got hip to the importance of native perennial grasses in carbon sequestration and soil water retention hearing presentations by Wendell Gilgert, Working Lands Program Director at Point Blue. He was talking about some remarkable rangeland restoration projects he's done (the projects are now collectively called the Point Blue Rangeland Monitoring Network, I think). He left the impression on me that California could turn its water problems around across the state if these native perennial grass pilot projects could be scaled up.

There are a whole lot of interesting articles and threads out there discussing the importance of nomadic herding and pastoralist culture to maintenance of healthy grasslands, but I'll save those for another future parking lot post.

Some Good News from the Southern Ocean, the Arctic, and Republican Pollsters

Since most news about climate change falls in the two categories of "confirming our worst fears" and "creating new, more depressing fears" I thought I'd share a few tidbits of recent good news.

• Southern Ocean Showing 'Remarkable' Revival in Carbon Absorption Ability (Sept. 10, 2015, The Guardian) about a new report of results from a 30-year study, The Reinvigoration of the Southern Ocean Carbon Sink by Landschützer et al. (Sept. 11, 2015, Science)

The downside mentioned by one of the study's lead scientists, Nicolas Gruber - "One has to recognise that despite this remarkable increase in the Southern Ocean carbon sink, emissions have gone up even more."

• Survey of Republican Voters Shows a Majority Believe in Climate Change (Sept. 28, 2015, NYT)

The downside of this good news is that it describes the attitudes of potential voters, not Republican elected officials or candidates for the top office of the country. Potential voters are not the same as political party influencers, unfortunately. The more extreme voices are appearing to win the day in terms of how the elected/ would-be elected leadership is positioning itself on climate change.

• Shell Exits Arctic as Oil Slump Forces Industry to Retrench (Sept. 28, 2015, NYT)

I don't see any downside here!

This Sept. 28, 2015, BBC article has some helpful maps illustrating the location of the Shell test drilling site with respect to the ice extent and international boundaries.

The Arctic will never be safe from the threat of oil drilling as long as we use oil in our energy stream, but for "the foreseeable future" it is safe from Royal Dutch Shell.

Meanwhile, the Russian oil production project by Gazprom Neft is still active in the Pechora Sea, drilling at the Prirazlomnoye Arctic field, apparently unaffected thus far by sanctions, unlike the Rosneft/Exxon joint drilling project in the Kara Sea.

Still further north from the Gazprom Neft project, the "Goliat" platform, owned by the Italian energy group Eni and Norwegian company Statoil, is in place at the border of the Barents Sea and Norwegian Sea. According to the BBC article cited above, it "could soon start producing oil ... within weeks." So, the Arctic Oil Rush is underway, just without one of the world's biggest oil multinationals.