They actually need fire to crack the seed and cause germination. These plants grow more slowly than the sprouters because they do not have the massive food reserve with which to get a head start. Within a few days of the fire at Stunt Ranch, bunch grasses and the yucca were showing green. The new green growth of the singed leaf of the yucca showed where the leaf kept growing after the fire. The prolific wild cucumber vine was also quick to reappear and helped to protect the soil from erosion when the rains came.
Erosion is a major concern after a fire.
Remember that the chaparral plants have deep roots. Even if the top of the plant dies, the roots are still there and will help to prevent erosion. The baking of the soil results in a shiny, impenetrable varnish which causes the water to run off and increases surface erosion. Soil heats and expands during a fire then cools and crumbles. Soil covered by white ash indicates that the fire was very intense in that area and that all of the organic matter volatalized leaving behind minerals such as nitrates and phosphates.