Burning Characteristics of Live California Chaparral and Utah Leaf Samples

Live sample leaves were burned in a laboratory facility at 1260 K with a heat flux of about 100 kW/m². Leaf temperatures were monitored using both thermocouples and an IR camera. Time to ignition, flame duration, flame height, and the leaf temperature at ignition were measured and correlated versus variables such as leaf thickness, moisture content, surface area, and leaf mass. Over 1000 samples were measured for four California leaf species (manzanita, scrub oak, horyleaf ceanothus, and chamise) and four Utah leaf species (big sagebrush, gambel oak, canyon maple, and Utah juniper). Moisture content and leaf thickness seem to correlate for many species. Ignition temperatures for different species vary by over 250 C, and seem to correlate most with leaf thickness (i.e., volume to surface ratio). Burning time seems to correlate with initial mass.