What is known is that Joshua trees grow slowly—typically only 3 to 5 centimeters a year. In order to track the progress of their growth and better understand their general health, the NPS closely monitors the trees and uses a series of methods to help track progress so we can better understand and protect them.
Here’s how it works: after using GPS coordinates to locate a research zone determined by the NPS, we mapped out a 50 x 50 meter zone and measured all of the Joshua Trees within that square. We recorded location, height, diameter, growth traits, and health of the trees. By looking at the density of the trees in the area as well as the status of the plants—dead, alive, or sprouting—this data helps researchers understand how the trees are growing and what we can do to ensure their survival.