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On newly-planted lands containing a fair supply 

 of humus, such as on deep 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 planted in land having a deficiency of humus 

 will not make satisfactory growth, and that com- 

 pound 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. to the acre 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 

 flower, and it should first be rolled down by short 

 intervals abreast of the plough, so that the plough 

 is able to turn the crop under. 



As the clean system of summer cultivation that is 

 necessary to practice under irrigation burns up the 

 humus in the soil, it is advisable to plough in green 

 crops in established orchards at regular intervals. 



