Many chaparral species show an interesting ecological adaptation 

 to repeated burning. This adaptation is crown-sprouting, which 

 refers to the fact that although the above-ground portions of a 

 chaparral shrub may be destroyed by a hot brush fire, the indi- 

 vidual produces numerous new shoots that develop from a large 

 burl that terminates the root system at or below the soil surface 

 (Plate 4B). As a result of this trait, crown-sprouting chaparral 

 shrubs are able to re-establish themselves immediately after a fire 

 and do not go through a successional re-establishment procedure 

 via seedlings. However, some chaparral shrubs are not crown- 

 sprouters, and these species are killed by hot fires and must pro- 

 duce seedlings in order to become re-established on a site. The 

 advantage of crown-sprouting is that it eliminates the uncertain- 

 ties of seedling establishment, which in arid climates may be 

 considerable. 



Chaparral is prone to burning because the shrubs are dense, 

 close together, and have rather dry evergreen leaves. Once a fire 

 gets started in Chaparral, it may spread rapidly and extensively. 

 The heat of chaparral fires is often intense. Temperatures of 

 1200° F (649°C) have been recorded at the surface of the soil in 

 burning Chaparral; one and one-half inches (3.8 cm) below the 

 soil surface the temperature may reach well over 300° F (149°C). 

 The biotic effects of chaparral fires are several. One of these is 

 the heating of the soil; another is that the fires remove the vege- 

 tation and thus allow more light to reach the soil surface. The 

 improved light conditions, plus the absence of root competition 

 and the vaporization of allelopathic compounds of shrubs, allow 

 the establishment of a lush herbaceous flora the first season after 

 chaparral fires. Although herbaceous annual plants are notably 

 uncommon under or near chaparral shrubs, their immediate and 

 abundant appearance after a fire indicates that their seeds are 

 present in the ground. 



There are a few plant species in California that are found only 

 after fires have swept through an area. These include Whispering 

 Bells {Emmenanthe penduliflora, Hydrophyllaceae) and one of 

 the native snapdiagons. Antirrhinum comutum (Scrophulari- 

 aceae), both annuals. Other species such as the poppy (Papaver 

 califomicum, Papaveraceae),P/zace//fl brachyloba (Hydrophyl- 



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