Carbon Sequestration and Salvaged Urban Lumber
We often hear that trees "clean the air" or "capture carbon," but what does that really mean—and what happens to that carbon when a tree comes down?
At Urban Lumber Los Angeles, our work exists at the intersection of environmental stewardship and craftsmanship. We’re committed to not just salvaging wood, but also helping our community understand why that matters—especially when it comes to climate impact.
🌳 How Trees Sequester Carbon
Trees pull carbon dioxide (CO₂) out of the atmosphere through photosynthesis. They use the carbon to build sugars, which in turn become the cellulose, lignin, and other structures that make up their trunks, limbs, and roots. This process removes carbon from the atmosphere and stores it in solid form within the tree.
Roughly 50% of a tree’s dry mass is carbon.
As long as the tree is standing—or the wood is preserved—that carbon stays out of the atmosphere.
🪓 What Happens When a Tree Is Cut Down?
When a tree is cut down and left to decompose, most of that stored carbon is released back into the atmosphere as CO₂ (and some as methane in anaerobic conditions). The same happens when trees are chipped for mulch, burned, or sent to landfill.
That’s why urban wood salvage is so important: it preserves the carbon by turning the trunk into long-lasting products like furniture, flooring, or architectural elements.
If you use salvaged lumber to build a dining table, that carbon stays locked away for decades, even generations.
🧮 How Much Carbon Is Stored in Salvaged Wood?
Here’s a simplified way to estimate the carbon sequestered in milled wood:
🔸 Step 1: Estimate the dry weight of the wood
Use a wood density chart (e.g. 35 lbs/ft³ for oak, 28 lbs/ft³ for sycamore) to calculate the dry weight of the lumber you’ve milled.
Dry Weight (lbs) = Volume (ft³) × Species Density (lbs/ft³)
🔸 Step 2: Estimate the carbon content
About 50% of the dry wood weight is carbon.
Carbon (lbs) = Dry Weight × 0.5
🔸 Step 3: Convert pounds of carbon to CO₂ equivalent
Each pound of carbon equals about 3.67 lbs of CO₂ equivalent, because of how carbon bonds with oxygen in the atmosphere.
CO₂ Equivalent (lbs) = Carbon (lbs) × 3.67
Or in metric: CO₂ Equivalent (metric tons) = Carbon (kg) × 3.67 ÷ 1,000
🔍 Example:
Let’s say a salvaged tree yields 250 board feet of dried hardwood (about 20.8 cubic feet of solid wood). For oak at 35 lbs/ft³:
Dry Weight = 20.8 ft³ × 35 = 728 lbs
Carbon Stored = 728 × 0.5 = 364 lbs
CO₂ Equivalent = 364 × 3.67 = 1,336 lbs of CO₂ (about 0.61 metric tons)
That’s more than half a ton of carbon emissions prevented just by milling and preserving one tree’s trunk.
🌍 Why It Matters
When we help a homeowner salvage a tree and turn it into usable wood, we’re doing more than creating a beautiful piece of material—we’re keeping carbon out of the atmosphere.
It’s a small action in the big fight against climate change, but it adds up.
Preserving urban wood helps reduce emissions, conserve resources, and strengthen local supply chains. It's also a powerful reminder: we can honor the life of a tree long after it's fallen.
If you have a tree on your property and you're wondering whether any part of it can be saved, reach out. We’re happy to help you assess it and, if possible, preserve both its memory and its carbon.
