THE DICTIONARY 
OF GARDENING, 
Layering—continued. 
be placed together, and the branch allowed to enter at 
the bottom. The pot must be afterwards filled up with 
soil, and made secure, by some means, from falling apart 
or shifting about. A covering of moss over the pot 
tends to keep the soil moist, by preventing an undue 
evaporation, resulting from its suspension in the air. 
This is sometimes called the Chinese method of Layering, 
presumably on account of it being more generally adopted 
in China. 
Some plants—Cordylines, for instance—will form roots 
readily in a moist stove, if an incision is made in a firm 
part of the stem, and some moss tied round, without soil. 
The moss must be kept syringed, and the old roots of the 
plant somewhat dry, until new ones are formed at the place 
desired. 
Layers should, in all cases, be allowed to become well 
rooted before being detached. 
- LAYIA (named in honour of Thomas Lay, naturalist 
in Beechey's voyage). Syns. Eriopappus, Madaroglossa. 
Including Callichroa, Calliglossa, and Owyura. ORD. 
Composite. A genus comprising about a dozen species 
of hardy, pubescent or hirsute, often glandular, mostly 
annual herbs, natives of North America. Flower-heads 
heterogamous, pedunculate; rays yellow or white; disk 
yellow; achenes pilose or rarely glabrous. Leaves alter- 
9 77 narrow, entire, or the lower ones rarely all pinna- 
ifid. 
duced, thrive in any ordinary garden soil. Propagation 
may be effected by seeds, sown on a hotbed. 
I. Calliglossa (Calliglossa). This differs from L. chrysanthemoide. 
- principally in ane a — 5 of usuall 2 to ei itech) 
unequal, rigid, subulate awns. California. SYN. Oxyura chrysan- 
themoides (under which name it is figured in B. R. 1830). 
L. n (Chrysanthemum-like). /l.-heads solitary, 
on su vate peduncles, tomentose ; e at base, 
paler at apex, broad-obiong, trilobed ; pappus none. August 
and Se ber. J., lower ones pinnatifid; up 
entire ; all slightly scabrous on the margin. 
L. s (broad-tongued). This is the correct name of the 
p nt described in this work as Callichroa platyglossa. (B. M. 
S. B. F. G. ser. ii. 373.) 
LEADWORT. See Plumbago. 
LEAF. A Leaf is an expansion of the cellular tissue 
of the stem, traversed by fibro-vascular bundles. The 
use of Leaves is to,afford a large surface for exposing 
to the action of sunlight and heat the food absorbed by 
the plant, and thus cause assimilation; they also provide 
for evaporation, and absorb the carbonic acid of the air. 
The various terms employed in describing the shape, 
duration, and insertion, &c., of leaves will be found in 
their proper places in this work. 
LEAF BUDS. See Buds, Leaf. 
> . One of the divisions of a compound 
-~ LEAF-MINERS. Many plants are liable to have 
their leaves mined, by the larve of minute insects, which 
may belong to various groups—Beetles (Orchestes Fagi in 
Beech-leaves, &c.), Sawflies (species of Fenusa, &c.), 
i (species of Lithocolletis, &c.), and Diptera 
(species of Phytomyza, &c.). In general, the affected 
rmost ones quite 
. 14ft. California, 
mines, unless these are very numerous. This is fortunate, 
È as the only remedy is to crush the larve in the leaf 
between the finger and thumb—a remedy not suitable for 
ae LD. Leaves, when thoroughly decayed, 
9 so that they readily separate into small particles, constitute 
What is termed Leaf Mould, a valuable manure in many 
instances, especially on heavy soils, and one of the most 
important ingredients for the soil used in the successful 
cultivation of the majorit pot plants. If of good 
quality, and free from in} as fungoid growths, it may 
The species, not many of which have been intro- 
plants seem to suffer little harm from the existence of the 
soil, or covering very lightly, for preserving moisture, is | 
extensive application. See also Celery Fly, Holly-leaf 
Leaf Mould—continued. 
be used freely, particularly with tender seedlings and 
cuttings of soft-wooded subjects. The production of roots, 
in young plants of this description, is induced and ac- 
celerated with more certainty by planting in the material 
under notice than by the use of any other. The quality 
of Leaf Mould depends very materially on the sort of 
leaves composing it, and in the manner of preparation 
adopted. The best leaves are those collected from a wood, 
or other place, where the principal trees are Beech and 
Oak, and where their leaves fall over a large surface 
each year, and naturally decay slowly until those beneath 
the surface become changed into a light mould. In many 
instances, such Leaf Mould cannot be obtained, on ac- 
count of the necessary removal of the leaves to preserve 
tidiness; but, on the other hand, its importance and ad- 
ditional value over that artificially prepared is insuffi- 
ciently recognised in many places where quantities might 
be collected in woods. Leaf Mould of good quality may 
be used to the extent of about one-third in composts for 
Azaleas, greenhouse Rhododendrons, and many fine-rooted 
hard-wooded plants of this description. It may, with 
advantage, be freely incorporated along with peat in ` 
preparation of beds for nearly all Ericaceous 
outside. Further, nothing is better suited for impro 
flower-beds, or for adding to soil of any description 
placing round trees, shrubs, or plants, whose roots it 
desired to encourage. If leaves have to be ga 
into a heap for Leaf Mould, a place should be selected 
where they may be spread rather thinly, so as to avoid 
any excessive heating by fermentation. The whole should 
be turned over occasionally, so as to expose all parts in 
turn to the influence of the weather and air. Where air 
cannot reach leaves that are of a somewhat hard, dry 
texture, their decay is exceedingly slow, unless there are 
other substances intermixed to hasten decomposition. _ 
Water may be applied artificially for the purpose, but 
it never has the same effect as rain; and if a large heap 
is made, this latter cannot penetrate far into the interior. 
Leaves should be collected free from sticks, if possible, 
as these are liable to encourage fungoid growths, which, 
finding a suitable medium for increasing in the Leaf 
Mould, will, in due course, render it useless for plant 
cultivation. The time taken in reducing leaves to a 
mould or fine soil depends greatly on the amount of 
turning over, and other attention devoted to the pre- a 
paration. Much may be done in one year, or even less; Lo 
but the quality is usually better if a longer time than 
this is allowed. 
LEAF PROPAGATION. The propagation of 
plants by their Leaves is a method of rapid increase 
adopted with great advantage in the case of those which 
succeed. An incision made in any firm part of the midrib, 
as well as the petiole, will, in certain instances, induce the 
production of a young plant. Ornamental-leaved Begonias, 
Gesneras, Gloxinias, and several succulent plants, are 
familiar examples of subjects largely increased by Leaf 
Propagation. Doubtless, many other sorts of plants 
might be similarly perpetuated, if their leaves remained 
fresh for a sufficiently long time to enable a callus to form. 
Leaves which are nearly fully matured, but still not too old, 
are preferable for propagating purposes; they will not sue- 
ceed at all if very young. Merely pegging them on light 
generally sufficient, with the protection of a close frame or 
bell glass. Succulents, increased by Leaf Propagation, should 
have their fleshy leaves simply laid on or very lightly 
pressed into sand, and be kept nearly dry on a shelf 
until a small bulbil-like plant forms at the end of each, 
where it has been detached. The propagation of plants 
by leaves is generally limited to the petiole or ribbed 
portion. Bryophyllum calycinum is, however, an excep- 
tion, as young ones spring, in this case, from the 
notches on the margin of the leaf. e 
