24 Agi'icuUural Gazette of N.S. W. [Jan. 2, 1908. 



Hawkesbiiry Agricultural College and 

 Experimental Farm. 



Plant Propagation. 



[Continued from December, 1907, page 944.] 



HUGH RKID, 



(lardener, Hawkesbury Ami<ultuial College. 



Propagation by Layers. 



A LAYER is a branch or shout, part of which is iiitrothieed into the soil, and 

 strikes root Avhilst being fed by tlu> i)nr(Mit ))l;nif. with which, however, its 

 communication is partially interriiiilcd 1n induce tlic returning sap to form 

 roots where checked, instead of returning in tlic parent stock. It has already 

 been stated tliat when absorbed by the roots, the sap passes ti])wards through 

 the alburnum .)r cambium layer, and the youngest layers of wood, to the 

 leaves, a)id tlint having been exi)osed in the tissue of these in the influence 

 of light, it returns by the liber or inner bark, forming woody matter and 



A Callus formed on the end of a cutting that has been buried upside 

 down previous to being set out in the ground to strike. 



(See December, 19(1", iMge !it:'..) 



depositing secretions in its ])rogress. a ])nrtiou extending to tlie roots, to 

 which it supplies organised matter fur the growth of tlu' spujigioles (the 

 tiny whitish portions at the extremities of the roots for absorbing water). 

 As the upward tluw of sap is by the young wood, it is evident that we nuiy 

 cut off from a l>i-;incli ;i ring of b:n-k, including the lilier oi- inm-r hni'k, 

 withont stopping the flow of saj) l)y the alburnnm. Tiie returning sap will. 

 however, be deprived of its regular channel wlien it reaches the place where 

 the onter and i}nier bark were removed b.v ringing. If this jiart is kept in 

 dry air, the obstructefl sap forms a swelling on the upper edge of the ringed 

 space, or if it protrudes a little in the form of a celhdar tissue, it soon dries. 



