TBG $^E)OOL OF SGRICULTURG, 
COLOMBO. 
Added as a Supplement monfhh/ to the “ TliOPIGAL AGRICULTURIST,” 
The following pages include the 
Agriculture for November : — 
VEGETABLE MANURES AND CHEAP 
EERTILIZEES. 
EGETABLE manures, like cattle 
manure, contain all the ingredients 
of ordinary crops, and hence may 
be called general manures, tliongh 
they are more slow-acting than 
cattle manure, and contain a larger percentage of 
water. They may he applied alone or mixed 
into a compost with cattle manure. Many of 
them contain an excess^ of nitrogen, and are 
sometimes classed under nitrogenous ma- 
nures. The action of green manures may he 
said to he three-fold : they act mechanically, 
rendering the soil more open ; they supply 
humus ; and lastly, they act as true manures, 
contrihuting the soluble ingredients of plant 
food to the soil. The value of vegetalde manures 
depends on the kind of plant as well as the part 
of the plant used. When crops (such as the 
legumes) are ])loughed directly into the land upon 
which they are grown for the special purpose 
of supplying a green manure, it is as a rule 
advisable that they shouhl ho taken out of the land 
just before dowering, as at this stage they con- 
tain the maximum of valuable ingredients in 
leaf and stem. Eor green manuring by burying 
in the whole croj), rapid-growing plants are most 
suitable. Sometimes the crop-residue only is used 
after the harvesting of the crop, and in the case 
of leguminou.s crops it has been often found that 
the root-system is e((ual in weight to the weight 
of the crop above ground, The roots of this order 
contents of the Magazine of the School of 
of plants when buried in the soil have a very 
benefleial effect on poor soils. 'Whatever may bo 
the doubts that exsit as to the exact manner in 
which the leguminosae improve the soil by 
accumulating nitrogen in the land, that they do 
so, and that the ])loughiug in of them or any part 
of them improves the condition of soils, there 
can be no doubt of. 'Where the croj:) grown on the 
land is ploughed in, the main advantage derived 
is that the ingredients of plant food are collected 
and placed in a proper position and condition in 
the soil. Where, however, the green crop is 
transferred to the land, there is a distinct impor- 
tation of plant food into the soil. 
Peat is useful for soils deficient in organic 
matter, good dry peat containing about 1 per 
cent, of nitrogen and from 5 up to 20 per cent, 
of mineral matter, which contains fair proportions 
of phosporic acid and potash. Peat decom- 
poses very slowly, and is best composted with 
lime. It is sometimes charred, and the residue 
used as a fertilizer either directly or after absorb- 
ing liquid manure. The charring process, hoAv- 
CA’er, causes the loss of almost all the nitrogen. 
Peat often contains injurious ferrous salts, and 
hence it is a good plan to treat it Avith lime before 
applying it to land. 
Coconut husk should be applied in as fine a state 
of division as possible in the form of coir dust. The 
so-called coir dust as supplied from mills is often 
found to consist of husk for the most part in a 
long flln'ous condition. It contains from 2‘o to 
••5 of nitrogen and a fair proportion of mineral 
matter. Coconut fibre is a good mechanical agent 
and a splendid absorber and retainer of moisture. 
Tanner’s bark, OAving to its hardness and thick- 
ness, decomposes Avith very great difficulty, and 
is therefore best a])plied after burning in spite of 
the loss of nitrogen ayIucIi results. 
