26o 



REPRODUCTION 



temperature, produce buds and roots which develop into new 

 plants at points where the midribs are cut. 



In the majority of cases, however, shoots are selected for 

 cuttings : they generally give best results 

 when cut through just below a node, for in 

 most instances it is only at the latter points 

 that adventitious roots are formed. Those 

 of leafy herbaceous plants are placed in 

 loose, warm .soil to induce a rapid formation 

 of roots and are kept in a somewhat close 

 damp atmosphere to prevent too rapid loss 

 of water by transpiration during the time that 

 the shoots are without roots. 



Woody cuttings contain a sufficient store 

 of food for the formation of callus-tissue 

 and roots : herbaceous cuttings, however, 

 usually possess but very small amounts of 

 ready - formed plastic materials and must 

 therefore be exposed to light so as to carry 

 on the work of ' carbon-fixation.' 



Currants, gooseberries and vines are very 

 readily increased by cuttings : pears and 

 apples may also be reproduced in a similar 

 manner, but the production of roots by the 

 shoots of these trees is very uncertain. 



The cuttings of fruit trees are usually 

 8 or lo inches long and taken from well- 

 matured wood of the previous season's 

 growth, after the shoots have lost their 

 leaves in autumn. The buds on the portion 

 of the shoot inserted in the soil should be 

 cut out where ' suckers ' are to be avoided, 

 and only the buds needed for the formation of the bush or tree 

 left on the part above ground (Fig. 91). 



Fic. 91. — Cutting 

 of gooseberry showing 

 formation of adventi- 

 tious roots below 

 ground. 



