Tree-planting apps, search engines that plant trees and carbon projects mostly pay per sapling in the ground, so the incentive ends on planting day and many seedlings die unseen. Carbon credits do pay over time, but only for big projects that can afford audits. Tree Annuity pays a small farmer for every year a specific tree is still alive and growing, proven by a seasonal geotagged photo that AI compares with the last one. The payment is for survival, which is what everyone actually wanted.
The data it runs on
Planter photos: taken in-app (no gallery uploads), with GPS, time, compass heading and device attestation stored with the image.
AI checks: a vision model compares the new photo with the registration photo and last season's: matching landmarks and bark or branch structure (same tree), leaf colour and canopy cover (alive), and height against a reference object or the planter's measuring stick (growth).
Satellite for larger plots: free Sentinel-2 imagery from the European Copernicus programme, 10 m pixels, a new pass about every 5 days, accessed through public catalogues. We compute NDVI (a greenness index) for the plot each season.
Limits and gaps: 10 m pixels cannot see a single seedling, clouds hide plots in rainy seasons, and photos can be staged.
Fallback: plots combine satellite trend with random sample photos of numbered trees; cloudy seasons use the next clear pass; suspicious photos go to a human reviewer and a local verifier visit.
1. The mission
Turn trees into a small, steady income for the people who keep them alive. Sponsors pay for living trees, year after year, and can see every one of them.
2. Why people can't resist it
A tree you can watch grow: sponsors get a new photo of their tree every season, a living album that is hard to stop following.
Steady money for planters: a payment every season is a reason to water in the dry months.
Honest numbers: survival rates are public, including the trees that died. People trust what they can check.
3. How it works for real
Register: planter signs in with a phone number, a smart wallet is created behind the scenes (Coinbase Smart Wallet, Privy or Dynamic). They photograph the tree with a reference stick; GPS and time are attached.
Check: each season a vision model (Gemini 2.5 Flash or GPT-4o class via OpenRouter) runs three checks: same tree, alive, growing. A fast cheap model writes the planter a plain explanation in their language. Low confidence goes to human review.
Plots: a scheduled job pulls Sentinel-2 tiles, masks clouds and computes NDVI per plot; a frontier LLM writes the seasonal plot note.
Pay: sponsors fund an escrow in USDC on Base (card top-up through an on-ramp). Each passed check releases that season's amount to the planter's wallet. Gas is sponsored by a paymaster, so nobody sees crypto. Planters cash out to mobile money or bank through an off-ramp partner.
Public record: every tree's checks (hash of photo, result, date) are logged, so the survival map cannot be quietly edited.
4. Cost per use
Pennies per check. A vision comparison is about $0.002 to $0.01; the explanation about $0.001; satellite imagery is free, with compute well under $0.01 per plot per season. Transfers on Base cost a fraction of a cent and are sponsored.
Free for planters.Sponsors: choose an annual amount per tree (for example $12 a year); 10% goes to running checks, local verifiers and payouts. Companies can sponsor whole plots with a public survival page.
5. Growth loop
Sponsors share their tree's yearly photo ("Year 3, still here"). Planters who earn tell neighbours, and each new planter brings trees that need sponsors. Cooperatives onboard whole villages at once. On the 1st of every month each sponsor gets a growth ping per tree, a growth chart and their grove balance, and adding a tree as a birthday gift pulls a new person into the grove.
6. Risks and guardrails
Fake photos: in-app camera only, device attestation, GPS plus heading, landmark matching across seasons and random human audits.
Land rights: planters confirm they own or have permission to use the land; cooperatives or local partners vouch for new planters.
Wrong species or place: species lists suited to each region; no invasive species.
Overclaiming: we never sell carbon claims from these trees. We report survival, not tonnes.
Privacy: exact coordinates are shown only to the sponsor; the public map is rounded.
7. MVP build order
Planter app: register a tree with photo, GPS and reference stick.
Season check with a vision model comparing two photos, plus human review queue.
Sponsor escrow in USDC on Base, released per passed check, gas sponsored.
Sponsor dashboard with the photo timeline, then Sentinel-2 NDVI for plots.