38 Fruitgrowing under Irrigation 



strip for the second and third years. In every case 

 the cover crops should be sown during the autumn 

 or early winter months, so that the crop is of some 

 considerable height by September, when the windy 

 weather begins. 



On newly-planted lands containing a fair supply 

 of humus, such as on (Jeep mallee soils, where it is 

 not necessary to plough in green crops for manure 

 for some years, the cover crops may consist of 

 cereals, such as wheat, oats, or barley. Wheat has 

 proved to be a very satisfactory cover crop for the 

 first three years among young trees, if drilled in 

 with manure in strips from 6 feet to 9 feet wide. 

 Enough hay can in this way be grown to keep the 

 grower's horses for some years, and provided the 

 crop is manured on a liberal scale, no injury to the 

 land or the trees should result. After the trees are 

 three or four years old they should have developed 

 sufficient growth to shelter the ground from the 

 worst effects of the wind, and cover crops for shelter 

 will no longer be required. 



Trees or vines planted in land having a deficiency 

 of humus will not make satisfactory growth, and 

 that compound must be added to the soil if the 

 orchard is to be a success. The cheapest way to get 

 humus into the soil is by ploughing in green crops. 

 The crops grown for this purpose are generally 

 legumes, such as peas, clovers, vetches, which 

 acquire, through the agency of the root-inhabiting 

 bacteria, the necessary nitrogen for their growth 

 out of the air, so that when they are ploughed in 

 both humus and nitrogen are added to the soil. Like 

 cereals, legumes are best sown or drilled in with a 

 good dressing of phosphates, say, 2 cwts., in the 

 autumn, so as to be well established before the cold 

 weather sets in. 



The best time to plough in is when the crop is in 



