228 TOE PEACH AND NECTARINE. 



forcing — forwarding force of the spring sunBhine ; the other saves them 

 from the hardly more destructive energy of spring frosts. 



Thicker and more opaque protectors mnst perforce be removed by 

 day, or the trees would be blanched into such weakness that they would 

 not only lose their fruit but also their health, and probably also their 

 life. An exception may, however, be made in favour of opaque copings. 

 These, whether formed of wood, common Eussian or other mats, or 

 thick painted glass, projecting 18in. or 2ft. over the wall, will often save 

 a crop of fruit without further trouble ; and if not applied till the trees 

 are almost in flower, and removed immediately, all danger from fiost is 

 over ; they do little injury to the trees. This is the chief reason why 

 peaches, nectarines, and apricots generally bear so freely on the gable 

 ends of fancy cottages, on the walls or sides of barns or outhouses. The 

 roofs of these project so far as to effectually protect the trees from the 

 killing severities of spring frosts. 



The attempt to neutralise the intensity of the cold by placiug water 

 in shallow tins at the bottoms of the trees has not been sufficiently suc- 

 cessful in practice to be worthy of serious recommendation. A certain 

 amount of heat is doubtless liberated from -water in the act of freezing. 

 But this is rather too infinitesimal to sensibly afEect the local atmo- 

 sphere in favour of the trees. As soon as the ice is formed the water 

 would tend to cool the air, so that to be of the slightest use the ice must 

 be skimmed off as soon as formed, and the plan is altogether too 

 chimerical in its practical results to be advocated here. The stems of 

 peach and nectarine trees are often much benefited by being protected 

 alike from frost bite and sun stroke by » piece of matting or hayband 

 being tied or twisted round them. 



II. — The Root and Top Watering. 



Few plants suffer more from a scarcity of water at the roots than these 

 trees. Not only does drought favour the production of fungi on or 

 about the roots, but it gives such a severe check to growth as produces 

 mildew and other evils on the leaves and branches, and diminishes the 

 size and lowers the quality of the fruit. Peaches and nectarines on 

 walls, with all their leaves and fruit exposed to the sun, must have a 

 continuous supply of food to make good the losses of evaporation and 

 elaboration. Stimulated by light and heat, the energy of these pro- 

 cesses and the expenditure of food on growth may become excessive. As 

 long. as the balance between waste and supply is maintained, the activity 

 of these processes la a clear gain to the tree. But let the demand for food 



