Water 



( 438 ) 



Water 



in the autumn, seek shelter, and remain torpid until 

 stimulated by the warmth of spring, though some- 

 times a specially bright winter's day arouses them. 



The first business of the awakened queen is to 

 seek or make a suitable hole in the ground wherein 

 to form a nest. With some wood scrapings as a 

 foundation, she erects two or three layers of cells, 

 lays an egg in each, and roofs the whole over. 

 Then more cells are made and eggs laid, and as 

 fast as the earlier eggs hatch the cell walls are 

 added to, in order to keep pace with the growth of 

 the grubs. Not only does the queen act as builder 

 and mother, but she has also meanwhile to forage 

 for the grubs, and when in search of food often 

 steals honey from bees. Presently the grubs turn 

 into worker wasps, and then the queen's work is 

 lightened ; but she continues to lay eggs, and from 

 those laid in early autumn perfect male and female 

 insects appear, which fly away from the old home 

 and secure the continuity of the species. The 

 males die, as do the worker wasps in the old nest, 

 their course being now run. 



The ovipositor of a wasp is also its sting ; males 

 have no sting. 



In some districts wasps are very numerous in 

 summer, and not only are they unpleasant neigh- 

 bours, but they do a good deal of damage to Pears, 

 Peaches, Nectarines, Grapes, and other fruits. 

 Wide-mouthed bottles containing sugared beer, or a 

 mixture of treacle and water, suspended in the 

 trees bearing ripe fruit, act as traps, but in some 

 cases it is necessary to keep the pests away from a 

 crop by covering the trees, or the ventilators and 

 doors in the case of Grapes, with thin canvas or 

 scrim. Sweet traps in a house often attract 

 wasps. 



" Taking " a wasps' nest is one method of 

 dealing wholesale destruction. This is done by 

 marking the entrance with a stake during the day 

 time, and in the evening plugging up the burrow 

 with damp earth and turf, except for a small hole, 

 through which a lighted squib of gunpowder and 

 sulphur is pushed. Immediately after the explo- 

 sion more wet earth is used to keep the powder and 

 sulphur fumes from escaping ; subsequently the 

 nest may be dug out, and if the gardener be a 

 disciple of Isaak Walton he will probably use 

 some of the grubs for bait. Cyanide of potassium 

 is likewise employed. 



By far the best method of reducing the numbers 

 of wasps is to carefully look out for and kill the 

 queens in early spring, as every one accounted for 

 means a whole colony the less during the summer 

 and autumn. 



WATER. 



Water is formed by the combination of two 

 gases, hydrogen and oxygen, in the proportions of 

 two parts of the former, by volume, and one part 

 of the latter. Calculated by weight, the proportions 

 are sixteen parts of oxygen to two parts of hydrogen. 

 The chemical formula is H.,O. When pure, water 

 is tasteless, colourless, and without smell, but it has 

 the power of attracting to itself and dissolving 

 various minerals and gases, so that it is very rarely 

 found pure. When, under the influence of frost, 

 it becomes ice, it parts with most of these mineral 

 substances e.g. ice formed from salt water. 



This property of dissolving mineral substances is 

 of the greatest importance to the gardener, seeing 

 that these minerals are in many cases part of the 

 essential food of plants, and that the plants cannot 



take them until they are dissolved. Water thus 

 becomes the vehicle which carries the supply of 

 food to the plant. (<$? also ROOTS. I'or the move- 

 ments of water in the plants, and details as to its 

 subsequent expulsion, see SAP.) The presence of car- 

 bonic acid gas (CO 2 ) in water enables the hitter to 

 dissolve small quantities of phosphates of lime, :is 

 well as other compounds in which lime is a factor. 

 Rain water usually contains a good deal of CO 2 , 

 as well as some oxygen, obtained from the atmo- 

 sphere, together with small quantities of nitrates 

 and ammonia from the same source. These are in 

 addition to the various mineral substances which 

 are in suspension in the atmosphere, and which it 

 collects during its passage. 



Rain water is preferred by gardeners to that 

 coming from other sources, as it is found to 

 exercise a more beneficial effect upon the plants 

 than other and " harder " waters. The reason for 

 this is to be sought in the gases dissolved in it, and 

 also in the fact that it is heated to about the same 

 temperatnre as the atmosphere in which the plants 

 are growing. This is where outdoor plants are con- 

 cerned. The temperature of water is a most 

 important point. In dealing with under-glass 

 plants the water should be of the same temperature 

 as that of the house ; it is a mistake to apply it 

 when cold, for it seriously lowers the temperature 

 of the soil, and causes a check to the roots, perhaps 

 at a time when the latter are working at pressure 

 to supply the needs of the top growth. 



Cold water is bad, but cold and hard water is 

 worse. Something may be done with naturally 

 hard water by allowing it to remain exposed to the 

 air in tanks and open reservoirs for a lengthened 

 period, but even then it is not so good as rain water. 

 Orchid growers generally contrive to keep up a 

 supply of soft water by catching the rain as it falls 

 from the houses, and conducting it into tanks to be 

 stored for use. A favourite plan is to have the large 

 tank underneath the floor of the house, the water 

 being dipped up, or pumped into a smaller cistern at 

 a higher level. A hot-water pipe running through 

 the tank is an excellent addition ; with it there 

 need be no fear as to the temperature of the water. 



It is safe to say, however, that much valuable 

 rain water is wasted, and also that much might 

 be done to economise the water obtained from the 

 clouds. On some estates a system of dew ponds 

 has been found to work well, and the writer has in 

 mind at least one establishment where a constant 

 supply of soft water is obtained by this method 

 where formerly little was to be had. In making 

 these dew ponds, advantage is taken of any slight 

 natural hollow that may exist, so as to reduce the 

 labour of digging. The holes are dug basin shape, 

 with a central depth of about 5'. The bottom 

 is puddled with plastic clay to which a little 

 lime has been added to toughen it. After pud- 

 dling, the bottom of the pond to be is thatched 

 with straw to prevent cracks being made by the 

 sun, and subsequent leakage. 



Although rain is the source of supply for all 

 springs and wells, the water obtained from them 

 varies a good deal. Very hard water i.e. that 

 containing a great deal of carbonate of lime is 

 not good for plants. Also it should not lie used for 

 filling boilers and pipes, for the carbonate is 

 deposited as a fur. clogging up the system. Iron 

 compounds are often dissolved in water, and 

 when this is the case the liquid is not always 

 suitable for giving to plants. 



