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The ecology of Giant Sequoia contrasts sharply with that of White Fir.in relation 

 to the importance of fire for reproduction and seedling establishment. In White 

 Fir, abundant seedlings are produced at relatively regular intervals of 5-10 

 years, with or without fire (Figure 3). There is no special mechanism tying seed 

 release to fire. Giant sequoias, however, are sharply tied to fire cycles or time 

 periods of decades or more. Light fires (LF) produce small peaks of seedling 

 production, but high denssities of seedlings critical for he maintenance of grove 

 populations occur only after relatively intense fire (IF) which occur far less 

 frequently (Figure 3). 



Giant Sequoia in the Mixed Conifer Ecosystem 



Giant Sequoias live not as isolated species, but as integral parts of the mixed 

 conifer forest ecosystem of the west slope of the Sierra Nevada. Modern 

 ecological understanding has advanced tremendously in the past few decades, 

 as has knowledge of the ecological relations and biological history of Giant 

 Sequoias. We understand much better now that Giant Sequoias, much as each 

 of us in our own society, is but one piece of a complex system of interacting 

 species and environmental factors. We cannot understand and preserve the 

 value of Giant Sequoias for future generations without understanding and 

 preserving the dynamic properties of the mixed conifer ecosystems of which the 

 Giant Sequoias are a part. The establishment, growth, and survival of Giant 

 Sequoia is greater than the simple sum of its genetic make up. Much more than 

 this. Giant Sequoia must be understood within the framework of its diverse and 

 complex biotic and abiotic environment. 



Appropriate ecological understanding and effective resource management of 

 Giant Sequoia and its preservation in the Sierra Nevada is impossible without 

 and understanding and protection of the mixed conifer ecosystem in which it 

 exists. 



How can we measure the importance of individual species within a mixed 

 conifer forest.? Are their other species of ecological significance in addition to 

 Giant Sequoias? As impressive as are the sizes of huge individual Giant 

 Sequoias in the Sierra Nevada, this species only makes up about one in twenty 

 trees in the groves in which they occur. Moreover, three-fourths of the growth 

 and productivity in these groves comes from other tree species. These include 

 White Fir, Red Fir, Sugar Pine, Incense Cedar, and Ponderosa Pine. All of 

 these tree species play an important role in dynamic cycles of fire, nutrient flow, 

 water cycling, and uptake of carbon dioxide from the atmosphere. Cycles of 

 growth and mortality in all of these tree species strongly influence patterns of 

 fire frequency and intensity, and thus very directly impact the dynamics of Giant 

 Sequoia. 



The biological diversity of the Giant Sequoia / mixed conifer ecosystem goes 

 well beyond the dominant tree species. Many mammals and bird species play 

 significant ecological roles in seed dispersal. Herbivores strongly impact seed 

 longevity and the survivorship of seedlings. Often unappreciated as well are 



