An Instagram account promised to plant a tree for every pet picture. 4 million posts later, where are they?

Read the full story in the Washington Post.

The promise was straightforward: “We’ll plant 1 tree for every pet picture.”

Within minutes, that prompt this week from an account called Plant A Tree Co. took off on Instagram. It became a global trend, with millions of people rushing to upload photos of cats and dogs — with many probably thinking they were helping the environment in the process.