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TEXTBOOK OF BOTANY 



buds may have been dormant for many years ( Fig. 84 ) . Under natural 

 conditions the plants become separated by breaking away naturally or 

 through the death of tlie parent plant. In practice these vegetative 

 propagules may be severed from the parent plant and transplanted. 



Fig. 188. Owing to its rapid vegetative multiplication by runners, the water 

 hyacinth, which is a floating plant, may completely cover the surface of slow- 

 flowing streams in the southern states and the American tropics. Photo by G. W. 

 Blaydes. 



Apical dominance at the tops of many plants prevents the growth of 

 shoots from the base of the stem. When the stems of such plants are cut 

 off, sprouts often grow profusely from the stumps. If regeneration b} 

 sprouts from the stumps is allowed to occur naturally after the trees of a 

 forest have been cut down, the next forest is largely a sprout forest, or 

 coppice. Since the sprouts on the stumps have a root system ahead}' 

 established in the soil, they may grow more rapidly than seedlings with 

 a comparatively small root system. Unfortunately, as the sprouts from 

 the larger stumps increase in age, their dead heartwood may be de- 

 stroyed by the same fungi that cause decay of the stumps. 



If the forest is repeatedly cut, such trees as chestnut and linden, which 



