Discovering the Ancients
Reporting Codes & Definitions
Download a PDF Key Chart Here.

Stem Crown… or Tree Trunk?

A plant that branches at ground level is called a shrub, no matter how tall it grows. The main stem of the shrub is called a "stem crown."

A plant that branches above ground level is called a tree, no matter how large or small. The main stem of the tree is called a "trunk."

Tree Trunk Graphic

How Does a Clone Form?

A clone is defined as: "a genetically identical assemblage of individuals derived from a single plant by vegetative reproduction." As the plant ages, it develops an expanding ring of identical shoots. These shoots eventually become separate plants, or clones. The diameter of the clonal ring can be used to estimate the age of the plant.

Terrain Codes

The following codes are used to describe the terrain:

F Flat

S Slope

W Wash

R Roadside

Age Estimate Method Codes

Please use one of the following codes to indicate what method has been used to estimate the age of the plant:

T TimeReader Card

C Clonal Ring Calculation

H Height Correlation

B Core Bore


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A brief description of Joshua Tree National Park, including weblinks for the U.S. National Park Service site as well as other sites of interest regarding the park.

Official NPS Web site:
Joshua Tree National Park

When you go out in the desert and actually look at the plants, and I mean sit and look at them, you begin to see the diversity and complexity this land has to offer. When you walk next to the plants and rocks of the desert, you begin to feel connected to them, as your grandparents would have felt, if they had lived here. It is not a harsh place, if you slow down and listen.

Curt Sauer, Superintendent
Joshua Tree National Park