LAYERS. 89 



lows: The bundles of cuttings are heeled in as recommended. 

 In the spring they are taken out, and buried close together, with 

 the butt ends uppermost, in a warm sunny spot, and covered 

 with about six inches of soil. A hotbed frame, with sash, is then 

 put over the spot, to warm the soil. Sometimes, instead of 



using sash, the soil over the cut- 

 tings is covered with a foot or 

 more of fermenting manure. In 

 either case the soil is warmed, 

 and the formation of roots 



encouraged. In using the solar 

 Figure 13. The solar pit, , . . ,, 



showing bundles of cuttings pit the rooting process should 

 in place under glass. not ^ e carr ied so far as to permit 



roots to show plainly, as they are liable to be broken off in 

 planting out; but the cuttings should be planted out as soon as 

 they show signs of healing over on the butt end. This healing- 

 over process is called callousing, and in many plants neces- 

 sarily precedes the formation of roots. 



LAYERS. 



I/ayers are portions of the branches of trees, shrubs or vines 

 which are covered with earth without being separated from the 

 parent plant and there take root and grow. These are cut off 

 from the main plant in autumn or spring, and form new plants. 

 Almost all trees and other plants can be rooted in this way, but, 

 while some root very easily, others require so long a time to do 

 so as to make it impracticable with them. 



The growing of trees from layers is seldom practiced in this 

 country, but in some European nurseries it is a common means 

 by which to increase special varieties of trees. For this purpose 

 what is commonly known as mound layering is often used. 

 This consists simply of drawing the soil up around the sprouts 

 that come from the stump of a tree, covering the base of them 

 about a foot in depth. It may be done at any time of the year 

 after the sprouts are two or more feet high, but preferably in the 

 spring. After the sprouts have become well rooted they may be 

 removed in spring or autumn and treated the same as seedlings. 

 Layering is sometimes practiced in European forests to fill up 

 vacancies, and a similar method is often employed in nurseries. 



