180 Principles of Plant Culture. 
tuft of leaves at its apex. The cane of the black-cap rasp- 
berry,* which roots from the tip (Fig. 81), and the runner of 
the strawberry (Fig. 82), that forms a plant at each node, 
are modified stolons. 
349. Propagation by Layers or Layering. The layer 
is an artificial stolon, i. e., a branch that does not naturally 
grow downward, which 
is covered with, or sur- 
rounded by moist soil 
to stimulate the pro- 
duction of roots (89). 
The branch may be 
bent down and cov- 
Fioc. 82. Runner of the strawberry, Fragaria. ered, as 1s usually prac- 
ticed with the grape, wisteria etc., or the soil may be ridged 
up about the branch, as is done with the quince and para- 
dise apple. In either case, the terminal portion of the stem 
should be left uncovered. In the latter method, which is 
known as mound-layering (Fig. 83), the stems are usually 
cut off just above the surface of 
the ground in early spring, to 
stimulate the formation of vig- 
orous shoots, which are ridged 
up about midsummer, or, pre- 
ferably, not until the succeed- 
ing fallorspring. The ridging == 
should be sufficiently high to Fic. 83. Mound-layering of goose- 
cover several of the lower nodes berry plants. (After Bailey). 
(116). Roots grow out at the nodes, and the shoots are | 
usually well rooted by the autumn following the ridging. 
* Rubus occidentalis, 
