Layer 



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Leaf Miners 



LAYER. 



A layer is a shoot that has been subjected to tlie 

 process of " layering," or laying down, with a view 

 to causing the formation of roots at. a definite 

 point, and the ultimate development of the shoot 

 into an independent plant. All layers should, if 

 possible, remain attached to the parent plant until 

 roots are emitted, but when tender subjects are 

 in question, and only a callus has been formed by 

 the allotted time, they may be lifted with a fail- 

 amount of safety. Fully 80 per cent, of callused 

 layers may be expected to root subsequent to 

 lifting. 



LAYERING. 



A method of propagation commonly practised 

 with plants of which cuttings cannot be made to 

 root readily when detached previous to rooting. 



Under the head of layering may be placed the 

 various operations known as "tongueing," "ring- 

 ing," " heeling." and " serpentine arching." These 

 are all variations of the same method, and a 

 common principle is at the bottom of them all. 



LAYERING. 



a, old plant ; b, young shoot ; c, e, leaves removed from shoot ; 

 d, tongue ; e, peg ; /, lo\ver soil ; g, mound of soil. 



Briefly, it is this : The sap ascends by the alburnum 

 or sapwood, and descends, after having been elab- 

 orated in the leaves, by means of the tissues of 

 the inner bark. By forming an obstruction to the 

 descent of the elaborated sap at any given point, a 

 tendency to root formation is established at that 

 point. 



There are many methods of setting up this 

 obstruction. The commonest, and, on the whole, 

 the best, is that of tongueing. To take a familiar 

 instance, the Carnation : The lower leaves are 

 stripped off the shoot to be operated upon until a 

 point is reached where the wood is beginning to 

 get firm. A sharp, thin knife blade is inserted in 

 the stem, just below a joint, and an upward 

 longitudinal cut is made, dividing the stem into 

 halves. The cut passes through the joint, and 

 altogether is about 1" long. The shoot is bent 

 towards the axis of the parent plant, the tongue 

 is thus opened, bent down, inserted in the soil, 

 and pegged firmly in position. It is imperative 

 that the tongue be kept open, or the wound will 

 heal and roots will not be formed. It is advisable 

 to place a layer of light, rich soil, about 2" deep, 

 about the plant that is to be layered. 



Alternative methods are to simply cut a notch 

 in the stem below a joint, or to remove a ring of 



bark, taking care, however, not to cut into the sap- 

 wood next to the bark. Neither of these, however, 

 is quite so expeditiously performed as tongueing. 



Serpentine arching is a term used to describe 

 the layering of rather long shoots that are situated 

 higher up the main stern than those of the 

 Carnation. " Piercing " is another variant, the stem 

 being pierced with the point of a sharp knife or 

 other instrument, and pegged down as before. 

 Layering by inserting the growing point is occa- 

 sionally done when other methods fail. " Twist- 

 ing" is an equally uncommon method. The ringing 

 of Dracaenas, Crotons, and Aralias follows similar 

 lines, moss, with which the wound is covered, 

 serving as soil. 



Layering by circumposition is an ingenious and 

 highly successful plan. To the shoot which has 

 been tongued or ringed a pot full of soil is 

 fixed. The pot is first split in halves, each half 

 being clasped about the stem, and subsequently 

 filled with soil. Strictly speaking, the so-called 

 layering of Strawberries is not layering, because 

 no attempt is made to obstruct the sap flow beyond 

 the slight compression of the stone or peg with 

 which the plantlet is fastened to the soil. 



Wire layering pegs may be bought cheaply from 

 the sundriesman, but excellent pegs can be made 

 from an old Birch broom or from the stems of the 

 common Bracken. 



LAYIA. 



Layias are neat hardy plants (ord. Compositse), 

 principally annuals, and having Daisy-like yellow 

 or white flowers. They are raised from seeds 

 sown in the same manner as other hardy annuals 

 (which see for treatment). They grow in common 

 soil in a sunny situation. Seeds sown in August 

 will give plants to bloom in spring. 



Principal Species : 

 Calliglossa, 1', Aug., yel. glandulosa, 1', Jy. , etc., 



(si/ n. pxyura chrysan- wh. 



themoides). heterotricha, T, Jy., etc., 



chrysanthemoides, 1', wh. 



Aug. , yel. platyglossa, 1 ' , Aug. , etc. , 



elegans, 1', Jy., yel., wh; yel. (syn. Callichroa 



there is a wh. var. platyglossa). 



LAYING IN. 



This term is used in connection with trained 

 trees, and is applied to new growths that have to 

 be trained, or laid in, between branches, the places of 

 which they will subsequently take. It is equally 

 applicable to fruit trees, flowering trees, and shrubs, 

 trained to walls or trellises, and from which old 

 growth is annually removed when it has fulfilled 

 its mission. The same expression is sometimes 

 used to denote a method, in vogue among good 

 gardeners, of roughly and quickly covering with 

 soil the roots of trees, shrubs, and herbaceous 

 plants when received from the nurseryman. This 

 laying in keeps the roots from harm until planting 

 can be properly performed. 



LEAF MINERS. 



These form a group of pests which are not easy 

 to cope with, as the adult insect pierces the leaf 

 cuticle, deposits an egg, and is gone again quickly. 

 In due course the grub is hatched and bores its 

 way between the upper and lower epidermis, 

 leaving in its train irregular markings that show 



Lcadmort (see Plumbago). 



Leatlier Wood (see Uircapalustris). 



