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EvILts oF IRRIGATION. 
Although irrigation has been a source of large profits to some, 
it may be said tu have, on the other hand, led in as many eases 
to considerable losses. The practice should only be adopted with 
judgment and after consultation with the specialists in charge of 
that work at the Department of Agriculture. The initial cost of 
leading water on to the land may be so great that the expenditure 
may not be justifiable. Moreover irrigation without efficient and 
thorough drainage is always fatal, sooner or later. The ground 
thereby alternately gets chilled and baked; there is no get away 
for the water except by evaporation; this cools the ground to a 
point which is uncomfortable and detrimental to vegetation and 
leads to the rotting of the roots. In irrigating or watering an or- 
chard, the water should never be Jed or poured into a cup-shaped 
bowl, dug around the stem. This causes a gummy exudation to 
ooze out at the crown of the tree, and the plant dies of collar rot. 
The stem should always be protected from actual immersion in 
water by a small mound of earth which is banked up around it. 
Irrigation on ground which is not naturally well drained, or 
where no attempt has been made to deep drain the soil, is often the 
cause of the displacement of masses of injurious alkaline salts from 
deep down towards the surface, where they finally accumulate and 
corrode the roots and stem and kill the trees. Much valuable in- 
formation on this rising of the soluble alkalies in irrigated soils is 
due to Professor Hilgard’s researches in California. It has been 
shown that the presence of as much as a quarter of one per cent. 
(.25 == 8,750]bs. on one acre of soil 1ft. deep) of carbonate of soda, 
one of the most corrosive of soil alkalies, renders that soil sterile. 
Over-irrigation is one of the greatest causes of failure in the 
hands of the amateur irrigationist. In a climate like ours, where 
the ground is well soaked during the winter months, there is little 
need to water the trees until early in summer if on deep loamy 
ground. Two or three more thorough waterings at intervals of a 
month, followed up by thorough cultivation and pulverisation of 
the surface ground, would thence meet the requirements of most 
trees. 
A good soaking is better than two or three niggardly waterings, 
which, instead of encouraging root growth deeper down into the 
soil, attract the tender rootlets towards the moistened surface, where 
they lie exposed, to be hacked about by implements of cultivation, 
or to be dried up should a hot, dry spell of weather set in. 
Water cannot be forced into the ground. Sufficient time must 
be allowed for it to soak, generally 12 to 24 hours 
The benefit derived from irrigation is often annulled by neglect 
to suitably, manure the land. It stands to reason that, if a soil can 
supply the necessary plant-food for half-a-dozen successive crops 
of, say, two tons of fruit to the acre, without showing any need 
