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The methodology followed 6 steps:

10x10 m sub-plots were defined before travel to the field. With the prior knowledge that it is impossible to measure DBH in the entire hectare due to constraints related to time and season (i.e., working in 40+ degree temperatures is dangerous and limits the amount of work that can be completed). Sub-plots were chosen at random, paced-out, and all live plants with a stem diameter in excess of 1 cm at breast height were measured. Altogether, six sub-plots were measured within the time constraints and given the heat load.

On each tree:

1. The tree was tagged with tree number using spray paint (large stems) or a copper tag (small stems).

2. Diameter was measured at 1.3 m above the ground with a DBH tape or callipers, depending upon DBH.

3. Each measured stem was identified with a spot of paint at the measurement point.

4. Dead stems larger than 1 cm between the base (20 cm above the ground) and BH were tagged and counted.

5. Height of each tree was measured with a laser rangefinder by taking a reading of the distance from a distant point (paced off for distance) to the base of the tree and the top of the tree. Height is determined by the rangefinder after entering the distance from the tree.

(6. Basal diameter at 20 cm height was also measured on each tree. While not a part of the scope of the DBH/H study, basal area is the most appropriate proxy for allometric scaling to biomass because the majority of the biomass in vegetation of semi-arid regions is below breast height. Basal diameters can be found in the worksheets for each individual sub-plot.)