By Jay Weiss, Cambridge Tree Project Executive Director
When the Cambridge Tree Project launched nearly 20 years ago, urban tree growth and survival data were nearly impossible to find. In response, I began tracking the trees my nonprofit donated to the Village of Cambridge to assess their performance.
To date, I have records for 1,375 trees planted throughout Cambridge and have taken nearly 9,000 annual tree growth measurements. This dataset, known as the Cambridge Tree Trials, is openly shared for educational purposes in the form of annual updates emailed to over 450 forestry professionals across America. To be added to the distribution list, email jay@cambridgetreeproject.org.
Summary: Total annual precipitation in 2024 was 23% higher than our 18-year average. Rainfall was especially pronounced over the first half of the year, and tree growth responded favorably by posting a 10% increase over historical levels (19.6 inches annually vs. 17.9 inches). Drought prevailed throughout late summer and early fall, however, as we noted our third consecutive year of warmer temperatures and prolonged periods without rain.
- Growth rates for 98 species
- Growth rate by genera
- Survival rates for 51 species
- Ambient cold hardiness observations
Faster Growing Trees: The following trees show above average growth rates in our tree trials. For credibility, this exhibit is limited to species with at least 100 total annual growth measurements. The average growth rate of all trees in our trials (nearly 8,000 growth calculations) is 18 inches. For all species’ growth rates see the link immediately above.
Growth Rate Over Time (all trees): There’s a linear drop-off from peak growth rates, between years three and five after planting.
The Tree Trials are a research-based entity affiliated with the Cambridge Tree Project.
More details on the Tree Project can be found online.