148 AUSTBALtAN AGRICULTURE. 



irrigation, in California, large areas of young wheat were 

 destroyed by over-watering, and for a time it was thought 

 that irrigation for wheat would not answer there ; watering, 

 it was said, brought on rust, but skill overcame that 

 mistake the watering had been overdone. The capacity 

 of all plants to take up water is dependent very largely 

 upon the extent of their roots ; so that, in watering, say a 

 bush-house, we may be starving some and drowning others, 

 while we continue to serve all alike, by using the sprinkling 

 pot or hose upon them. Thus, a young begonia may be 

 gorged with water, while its full grown sister alongside is 

 starving ; or it may be that a plant has not been shifted 

 and that its ball has been over-crowded with roots, and 

 after being repotted, all the water may pass through the 

 new soil while the interior of the hardened ball is dry, and 

 in that state it is so much slower in absorbing water. In 

 this way, shade-tree plants newly set out ; may be starved 

 for want of water. As a rule, the larger the leaf surface 

 of plants or the quicker they grow, the more water is 

 required. Plants with narrow leaves, or that grow slowly, 

 do not require water to the same extent. The quantity 

 of water required also depends to a great extent 

 on the situation in which they are growing ; thus, in the 

 moist atmosphere of a conservatory, evaporation from the 

 leaves is much less than in an airy bush -house. So with 

 wheat in comparison with maize, less water requires to be 

 pumped up by the wheat from the soil, and it is, therefore, 

 not necessary to give water so often. Among active water 

 absorbers are the ferns that naturally belong to moist, 

 mossy situations ; most of the orchids, when in baskets or 

 pots, require to have their roots kept constantly moist while 

 in a state of growth, though they endure almost complete 

 dryness when dormant. Various of our indigenous plants, 

 as rock lilies, staghorns, &c., although able to resist an 

 almost absolute condition of drought, yet to bring them to 

 perfection a regular supply of water must be given when 

 they are in a state of growth ; for, though they do not lose 

 much moisture by evaporation or breathing, a large 

 supply is needed to fill the tissues of the growing shoots or 

 leaves. 



