Is your fruit tree looking sick or bearing bad fruit? Fruit tree diseases are common: Here's how to identify the problem so you can effectively treat your tree.

Take a pencil and move several meters away from the tree. Outstretch your arm and hold the pencil so that you can measure the height of the tree on the pencil with your thumb.

There are various ways to measure plant health, and we’ve seen many projects creating open-source solutions. One we haven’t seen is a dendrometer, which involves measuring various physi… ...