Page:Encyclopædia Britannica, Ninth Edition, v. 12.djvu/245

233 MANURES.] HORTICULTURE 233 1 rjanic i i ores. beneficial on cold stiff soils. It should not &quot;be allowed to lie too long unmoved when fresh, as it will then heat violently, and the ammonia is thus driven off. To avoid this, it should be turned over two or three times if practicable, and well moistened preferably with farm-yard drainings. Cow dung is less fertilizing than horse dung, but being slower in its action it is more durable ; it is also cooler, and therefore better for hot dry soils. Thoroughly decayed, it is one of the best of all manures for mixing in composts for florists flowers and other choice plants. Pig dung is very powerful, containing more nitrogen than horse dung ; it is therefore desirable that it should undergo moderate fermentation, which will be secured by mixing it with litter and a portion of earth. When weeds are thrown to the pigs, this fer mentation becomes specially desirable to kill their seeds. The drain- ings of a pig-stye form a most valuable liquid manure for vegetable crops. Night-soil is an excellent manure for all bulky crops, but requires to be mixed with earth or peat, or coal-ashes, so as both to deodorize it and to ensure its being equally distributed. Quick lime should not be used, as it dispels the greater part of the ammonia. When prepared by drying and mixing with various substances, night-soil is sold as poudrette, or desiccated night-soil, the value of which depends upon the materials used for admixture. Malt-dust is an active manure frequently used as a top-dressing, especially for fruit trees in pots. It is rapid in its action, but its effects are not very permanent. Rape dust is somewhat similar in its character and action. Bones are employed as a manure with decided advantage both to vegetable crops and to fruit trees, as well as to flowers. For-turnips bone manure is invaluable. The effects of bones are no doubt mainly due to the phosphates they contain, and they are most effectual on dry soils. They are most quickly available when dis solved in sulphuric acid. Guano is a valuable manure now much employed, and may be applied to almost every kind of crop with decided advantage. It should be mixed with six or eight times its weight of loam or ashes, charred peat, charcoal-dust, or some earthy matter, before it is applied to the soil, as from its causticity it is otherwise not unlikely to kill or injure the plants to which it is administered. Pigeon dung approaches guano in its power as manure. It should be laid up in ridges of good loamy soil in alternate layers to form a compost, which becomes a valuable stimulant for any very choice subjects if cautiously used. The dung of the domestic fowl is very similar in character. Horn, hoof-parings, woollen rags, fish, blubber, and blood are all good manures, and should be utilized if readily obtainable. Sawdust and tan are of less value. Liquid manure, consisting of the drainings of dung-heaps, stables, cowsheds, &c., or of urine collected from dwelling houses or other sources, is a most valuable and powerful stimulant, and can be readily applied to the roots of growing plants. The urine should be allowed to putrefy, as in its decomposition a large amount of ammonia is formed, which should then be fixed by sulphuric acid or gypsum ; or it may be applied to the growing crops after being freely diluted with water or absorbed in a compost heap. Liquid manures can be readily made from most of the solid manures when required, simply by admixture with water. When thus artificially compounded, unless for immediate rise, they should be made strong for convenience of storage, and applied as required much diluted. Ammonia is the most powerful of the manures of the inorganic series, and one of the most important of the constituents of manures generally, since it is the chief source whence plants derive their nitrogen. It is largely supplied in all the most fertilizing of organic j manures, but when required in the inorganic state must be obtained j from some of the salts of ammonia, as the sulphate, the muriate, or the phosphate, all of which, being extremely energetic, require to be used with great caution. These salts of ammonia may be used at the rate of from 2 to 3 cwt. per acre as a top-dressing in moist weather. When dissolved in water they form active liquid manures. Potash and soda are also valuable inorganic manures in the form of carbonates, sulphates, silicates, and phosphates, but the most extensively employed is the nitrate of potush. The manures of this class are of course of value only in cases where the soil is naturally deficient in them. On this account the salts of soda are of less importance than those of potash. The value of wood ashes as a manure very much depends upon the carbonate and other salts of potash which they contain. Lime in the caustic state is beneficially applied to soils which contain an excess of inert vegetable matter, and hence may be used for the improvement of old garden soils saturated with humus, or of peaty soils not thoroughly reclaimed. It does not supply the place of organic manures, but only renders that which is present available for the nourishment of the plants. It also improves the texture of clay soils. Gypsum, or sulphate of lime, applied as a top-dressing at the rate of 2 to 3 cwt. per acre, has been found to yield good results, especially on light soils. It is also employed in the case of liquid manures to fix the ammonia. Burnt clay has a very beneficial effect on clay land by improving its texture and rendering soluble the alkaline substances it contains. The clay should be only slightly burnt, so as to make it crumble down readily ; in fact, the fire should not be allowed to break through, but should be constantly repressed by the addition of material. The burning should be effected when the soil is dry. Vegetable refuse of all kinds, when smother-burned in a similar way, becomes a valuable mechanical improver of the soil ; but the preferable course is to decompose it in a heap with quick lime and layers of earth, converting it into leaf-mould. Soot forms a good top-dressing ; it consists principally of charcoal, but contains ammonia, whence its value as a manure is derived. It should be kept dry until required for use. It may also be used beneficially in preventing the attacks of insects, such as the onion gnat and turnip fly, by dusting the plants or dressing the ground with it. Common salt acts as a manure when used in moderate quantities, but in strong doses is injurious to vegetation. It suits many of the esculent crops, as onions, beans, cabbages, carrots, beet-root, asparagus, &c. ; the quantity applied varies from 5 to 10 bushels per acre. It is used as a top-dressing sown by the hand. Hyacinths and other bulbs derive benefit from slight doses, while to asparagus as much as 20 K&amp;gt; to the rood has been used with beneficial effect. At the rate of from 6 to 10 bushels to the acre it may be used on garden lawns to prevent worm casts. For the destruction of weeds on gravel walks or in paved yards a strong dose of salt, applied either dry or in solution, is found very effective, especially a hot solution, but after a time much of it becomes washed down, and the residue acts as a manure ; its continued application is undesirable, as gravel so treated becomes pasty. 20. Tools, Implements, dr. With regard to garden tools, Tools. instruments, implements, and machinery, it is only some of the more modern inventions and im- provements that can be touched on here. The two indispensable tools are the spade and the knife. The spade is com monly used for digging and trenching, but much of this work is now better done by means of Parkes s digging-fork (fig. 42), which is both handier and lighter, and breaks up the ground better than the spade. The pickfork or Canter bury hoe (fig. 43) is a very useful tool for breaking up the surface soil, the three- pronged end being used for the looser parts, and the mattock end for breaking clods, or when the surface has become Fu: v - i T i, i mi i / 4 A much consolidated. Ihe drag (fag. 44) is also useful a light three-pronged tool, which may be used for loosening the soil amongst vegetable crops as well as flower garden plants, and may also be sometimes employed, if the tines are sufficiently narrow and pointed, to drag off weeds from the surface, The hand-fork (fig. 45), a short- Digging-Fork. Fio. 43. Pickfork. Flo. 45. Hand- Fork. FIG. 44. Dra: handled three-tiued implement, is extremely handy for many purposes, such as loosening weeds for hand-weeding, or for planting or transplanting small subjects; it is also very handy for plunging pots, either indoors or out, in tan- XII. 30