446 Journal of Agriculture, Victoria. [10 July, 1916. 



Drainage. 



The rains of winter will always show the necessity for draining or- 

 chards. Where undersoil drains do not exist, the trees are bound to 

 suffer. If the damage is n6t immediately apparent, it will be later found 

 that in some way loss will accrue. Either the tree will be weakened by 

 the loss of roots through rotting, or it will be devitalized so that it will 

 not carry a satisfactory crop of fruit. Too often surface drainage is 

 relied on to remove the so-called surplus water. There should be no sur- 

 plus wator for surface drains. The water is only surplus or excess when 

 it is in the soil. Two circumstances, and two only, permit of surface 

 drainage. First, when it is necessary to carry away excessive storm- 

 water; and, second, when it is practically impossible to find an outlet for 

 under-drams, owing to the low-lying situation of the area. 



The term " surface drainage " does not apply to open drains, which, 

 cwing to their depth, act also as soil drains; neither does it apply to 

 graded surfaces which allow a more equitable distribution of water. Sur- 

 face draining is usually applied to a system, whereby a considerable quan- 

 tity of water is removed by gravitation before it enters the soil. Such 

 a system cannot be too roundly condemned. As much water as can be 

 obtained by natural means should be induced to enter orchard soils ; and 

 then whatever is in excess will be carried away by under drainage, pro- 

 vided that drainage, either natural or artificial, be in existence. 



Where suitable drainage is not provided, the tree roots are compelled 

 to remain in a few inches of surface soil. Their feeding area is thus ex- 

 tremely limited indeed; and when, at any time, rain-water does filter and 

 penetrate through the soil, it carries with it the soluble and other plant 

 foods, below the reach of the tree roots. 



Soil ventilation is only possible with a system of drainage, and air is 

 as necessary to the roots of a tree as it is to the foliage. By the removal 

 of the surplus water and the consequent admission of air into the soil, 

 the soil temperature is rendered far more equable, warmer in winter and 

 spring, and cooler in summer; and such a change must be beneficial to 

 the trees. 



Drainage is thus an essential for all orchard lands. When natural 

 drainage occurs, the orchardist is fortunate ; but whether natural or arti- 

 ficial, a system of drainage will always materially increase the crop of 

 fruit, strengthen the trees, and considerably add to their term of life. 



Drainage schemes should be carried out at the present season of the 

 year. In closed drains, such drainage media as cinders, charcoal, stones, 

 brushwood, timber, logs, or tile pipes may be used, but the latter gener- 

 ally give more satisfactory and permanent results. They are also less 

 liable to silting up than any other materials. 



Drains should be placed into the clay, if this be not too deep. In 

 any case, they should be below any possible interference from cultiva- 

 ing instruments. 



Spraying. 



In order to keep in check such pests as Bryobia, scale insects, woolly 

 aphis, and others, a strong and forcible spraying with lime sulphur spray 

 should not be delayed any longer. The whole tree should be thoroughly 

 wetted with the spray. A good, vigorous, and thorough winter spraying 

 with lime sulphur will place a large majority of the trees in quite a 

 satisfactory condition of freedom from these pests for the whole year. 



