Citation
The -3/2 Self-Thinning Law
TL;DR
Every time average plant size doubles, about two-thirds die
Documents one of the most robust patterns in ecology - as plants grow, density decreases predictably according to the formula: log(density) = -3/2 × log(mass) + constant. This has been observed across hundreds of species.
The law explains why early growth is when most elimination happens: first 5 years kill 90-95% of seedlings, next 20 years kill 90% of survivors. The 0.1% that become mature trees survived the gauntlet.
Key Findings from ecologists (1980)
- Every time average plant size doubles, about two-thirds die
- You can have many small plants or few large plants, but not both
- Pattern observed across hundreds of species
- First 5 years kill 90-95% of seedlings
- Density decreases faster than mass increases