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A TEXT-BOOK OF BOTANY 



of the leaf is indicated by the leaf scar, immediately above 

 which the three buds appear. In the common bush honey- 

 suckle, three to six buds appear in each axil. 

 In all such cases the extra buds are called 

 accessory buds. 



33. Adventitious buds. Since the tips of 

 stems or branches and the axils of leaves are 

 the usual places for buds, those which occur 

 in other positions are called adventitious buds. 

 Such buds appear on stems (on the inter- 

 nodes), roots, and even leaves, and very 

 commonly they arise as a result of injury. 

 On the trunks of trees, even at the base, 

 wounds often result in the formation of buds 

 and the development of vigorous young 

 branches usually called suckers or water 

 sprouts. Often from a stump young shoots 

 arise, and the process of pollarding consists 

 in cutting off the crowns of trees that new 

 branches may be developed in connection 

 with the wound. In the willows, for example, 

 the production of such shoots is so prompt 

 and they are so vigorous and pliable that 

 twigs for basket-work are obtained from them 

 in this way. In propagating plants by root- 

 cuttings, as can be done with blackberries and raspberries, 

 advantage is taken of the fact that some roots can produce 

 buds. In propagating by stem-cuttings it is the axillary 

 buds that develop the new shoots; but in root-cuttings the 

 new shoots arise from adventitious buds. That leaves also 

 may produce adventitious buds is shown in connection with 

 the practise of propagating begonias by leaf-cuttings. 



It is evident, therefore, that while plants ordinarily 

 produce terminal and axillary buds, under certain con- 

 ditions buds may be developed and shoots arise at any place. 



FIG. 67. Branch 

 of maple, show- 

 ing terminal, 

 lateral, and ac- 

 cessory buds. 

 After GRAY. 



