52 



ESSENTIALS OF BOTANY 



grow much faster than others and so make the plan of 

 branching less evident than it would be if all grew alike. 



67. Alternate Branching. — In 

 trees like the beech the twigs will 

 be found to be arranged in a more 

 or less regular spiral line about the 

 branch. This, which is known as 

 the alternate arrafigement (Fig- 25), 

 is more commonly met with in trees 

 and shrubs than 

 the opposite ar- 

 rangement. It 

 admits of many 

 varieties, since 

 the spiral may 

 wind more or 

 less rapidly \^ 

 round the stem. 

 In the apple, 

 pear, cherry, 

 poplar, oak, and 



walnut, one passes over five spaces before 



coming to a leaf which is over the first, 



and in doing this it is necessary to make 



two complete turns round the stem. 

 68. Growth of the Terminal Bud In 



some trees the terminal bud from the 



very outset keeps the leading place, and Fm. 2u. Alternate 



the result of this mode of growth is to Branching in a very 

 . ,.^ . ,, Young Apple Tree. 



produce a slender, upright tree, with an 



excurrent trunk like that of Fig. 232. In such trees as the 

 apple and many oaks the terminal bud has no preeminence 



Fig. 24. Opposite Branch- 

 ing in a very Young Sap- 

 ling of Ash. 



