344 



THE DICTIONARY OF GARDENING, 



Saline Manures continued. 



some of the substances supply to the plants those 

 minerals that are required by all of them, as shown by 

 the chemical analysis of their ashes; e.g., Potassium 

 Chloride supplies to plants the elements Potassium and 

 Chlorine, both of which, but especially the former, are 

 required by them. Ammonium Sulphate, which is often 

 made use of as a Manure, supplies Nitrogen in a form 

 readily taken up by plants. Other Saline Manures 

 serve as food for the plants not only directly, but even 

 still more efficiently by rendering certain injurious acids 

 and other substances harmless, or by acting on various 

 substances already in the soil, changing them from an 

 insoluble to a soluble condition. Plants are able to 

 absorb the substances thus changed, and to employ them 

 as food. As examples of such Manures, Carbonates of 

 Potash and of Soda, and Gypsum or Sulphate of Lime, 

 may be mentioned. 



The views generally entertained in regard to the uses, 

 of the various elements in Saline Manures may be 

 summed up as follows : 



Potassium is concerned in the formation of starch, as 

 is shown by the absence of the latter from plants from 

 which the element is completely withheld. Such plants 

 soon cease to grow ; but growth is resumed on Potassium 

 being again given. Potassium Chloride is the best source 

 of this element for plants, and Potassium Nitrate (salt- 

 petre) is the next best. Potassium Sulphates and Phos- 

 phates are less efficacious. 



Sodium compounds are abundant in many plants near 

 the seashore ; but Sodium does not seem essential ; 

 at least, plants from which it is withheld often grow 

 equally well with others to which it is supplied. 



Calcium and Magnesium are always present, though 

 varying much in amount. The absence of Calcium checks 

 growth after a time; but the exact use of each element 

 is uncertain. Possibly, both benefit plants, " partly in 

 serving as a vehicle for Sulphuric and Phosphoric acids 

 in the absorption of food materials, and partly in fixing 

 the Oxalic Acid, which is poisonous to the plant, and in 

 rendering it harmless" (Sachs). 



Iron is required, though only in minute quantity, to 

 permit of chlorophyll becoming green, and doing its work 

 in the nutrition of plants; but most soils contain a 

 sufficient amount of Iron, and even a small excess is apt 

 to be injurious. 



The Saline constituents required by plants may be 

 supplied to any soil in which they are deficient, either 

 by adding such Manures as contain them, or by subject- 

 ing the soil to such treatment as will convert insoluble 

 into soluble salts. One of the most important Manures 

 is Kainite, a mineral brought from various localities, 

 including Greenland. It occurs in rock masses, and 

 consists of Potassic Sulphate, Magnesic Sulphate, and 

 Magnesic Chloride, thus supplying several important 

 elements. Other valuable Manures are mentioned 

 above. 



SALISBUBIA. A synonym of Ginkgo (which 

 see.) 



SALISIA (of Regel). A synonym of Gloxinia 

 (which see.) 



SALISIA (of Lindley). Included under Eunzea. 



SALIX (the old Latin name used by Virgil, &c. ; 

 connected with the Greek Lelike and English Sallow). 

 Osier; Sallow; Willow. OBD. Salicinece. An extensive 

 genus (about 160 species are enumerated by Anderson) 

 of mostly hardy trees or shrubs, broadly dispersed. 

 Flowers sessile ; catkins often dense, erect, in temperate 

 regions often early, sessile, and naked, in warmer and 

 frigid regions cosetaneous, leafy-pedunculate ; bracts small, 

 entire or rarely toothed. Leaves often narrow or small, 

 entire or serrulated, penniveined ; stipules variable. The 

 wood of the Willows "is soft and light, and is applied 



Saliz continued. 



to a great variety of purposes, especially for building 

 fast-sailing sloops of war, and for making cricket-bats. 

 Split into thin strips, it is manufactured into hats. The 

 twigs have, from the earliest antiquity, been employed in 

 basket-work, and in Pliny's time (as they are, indeed, at 

 present, in the Northern countries of Europe) were 

 twisted into ropes. The leaves of several species are, on 

 the Continent, used as fodder for cattle, being collected 

 in summer and stacked for winter consumption. In Sweden 

 and Norway, the bark is kiln-dried in seasons of scarcity, 

 and is mixed with oatmeal " (Lindley and Moore). The 

 species used for basket-making are commonly called 

 Osiers ; those best adapted for wicker-work are S. triandra 

 and 8, viminalis. Many species have been introduced 

 into England, but only the most desirable are described 

 in this work. Willows grow most freely when planted 

 near water, but they succeed almost anywhere in heavy 

 soil and damp situations. Propagated freely by cut- 

 tings, made by firm wood of almost any reasonable size. 

 Fungi. The Fungi parasitic on the various species 

 of Willows are rather numerous, though seldom so 

 hurtful as to seriously injure the trees or shrubs. 

 Hence, it is unnecessary to enter upon a long account 

 of them here, and only a few of the more generally- 

 diffused species will be mentioned. 



The leaves of most kinds of Willows are very apt, in 

 summer and autumn, to become covered with small, 

 yellow or orange spots, which, under a good microscope, 

 are found to be composed of groups of rounded, yellow 

 or orange cells, loosely massed together, and surrounded 

 by the torn edges of the epiderm or skin of the leaf. 

 These belong to a Fungus formerly known as Lecythea 

 caprearum, and as Uredo mixta. The cells are only an 

 early condition of a Fungus named Melampsora salicina. 

 In the latter stage, the Fungus occurs in spring, on leaves 

 lying on the ground, in the form of black spots, made 

 up of oblong, dark spores wedged as closely together as 

 they can lie side by side. 



Another very common Fungus on Willows assumes the 

 form of a black crust on the leaves and branches. In 

 its young state, it resembles a dark mould, and has been 

 named Fumago vagans ; but, when mature, it shows 

 elongated perithecia with asci, in which lie six brown, 

 multioellular spores. This mature condition is not fre- 

 quent. 



A third Fungus that attacks WiUows belongs to the 

 same group (Perisporiacei) as the last, but differs, in 

 colour, covering the leaves with a whitish coat (see 

 Mildew and Oidium). This parasite bears the name 

 of Uncinula adunca. The whitish coat is formed by the 

 Oidium stage. After a time, numerous perithecia are 

 formed on it, at first yellow, but afterwards becoming 

 black, each of which bears on its surface a number of 

 stiff hairs, hooked at the tip. For general structure, 

 see references just given. 



The leaves of Willows are often spotted by the growth 

 on them of certain Moulds, and of such genera as 

 Septoria and its allies, which are generally regarded as 

 young conditions of Fyrenomycetes (which see for 

 structure) ; but, beyond rendering the leaves unsightly 

 towards the end of autumn, they do not materially 

 injure the trees. The trunks of old Willow-trees are 

 liable, like almost all other trees, to serious injury from 

 the growth in them of mycelium of some of the larger 

 Fungi, the presence of which is indicated by the appear- 

 ance, on the exterior of the infected portions of the 

 trunk, of mushrooms, Polypori, or other reproductive 

 bodies, varying according to the species of the Fungi. 

 Trees thus infested are not worth preservation, and had 

 better be used as firewood than be left as centres of in- 

 fection. The Fungi that grow on the leaves are best got 

 clear of by sweeping up and burning all fallen leaves 

 in autumn. 



