and Magazine of the Ceylon Agricultural Society. 



587 



In cases where the soil is well supplied with 

 lime it is recommended to use Superphosphate, 

 and Basic Slag wherever thore is a deficiency of 

 this constituent. 



As a summary of the foregoing remarks, the 

 following manurial prescriptions, in addition to 

 green-manuring, may be laid down for the 

 different classes of soils : — 



I. Heavy soils doliciont in lime. 



Per tree. 

 Basic Slag ..- C lb. 



Sulphate of Potash .. "lh „ 



Sulphate of Ammonia . . 1 ,, 



11. Soils containing sufficient lime. 



Per tree. 

 5 lb. 



sh .. 1£ „ 



Nitrate of Soda . . „ 



III. Sandy Soils. 



Per tree. 



Ba3ic Slag . . 6 lb. 



Kainit .. 6 „ 



Sulphate of Ammonia. . 2 ,, 



These manurial recipes, of course, apply only 

 to trees which are in full bearing. In the case 

 of younger trees and trees planted more closely 

 together, the quantities of the different manures 

 for application per tree will have to be lessened 

 and calculated in the same way according to the 

 yield per acre. 



The above calculations were also made on the 

 assumption that the soil on which the almond 

 trees are cultivated is naturally poor. If the 

 soil be fertile, however, it is clear that the 

 quantities of tli9 manures may bo correspon- 

 dingly reduced. It is impossible here to enter 

 into details, but it may be stated generally that 

 the best and surest method of determining the 

 requirements of the soil is to carry out suitable 

 experiments. 



While the phosphatic aud potash manures 

 should be appliedand ploughed in iis the autumn, 

 or at the beginning of the winter, the Nitrate 

 of Soda or Sulphate of Ammonia will be more 

 advantageously applied in the spring and in- 

 corporated with the surface soil. 



In soils which contain an abundauce of lime, 

 good effects will be produced by tho use of Iron 

 Sulphate applied at tho rate of 40-70lb. per acre. 



In order to show finally the actual advan- 

 tages that may be obtaiued in practice by the 

 judicious manuring of the almond trees, we 

 may quote tho results of an experiment carried 

 out in 1907-08 by Mr Emilio Albiach in Ali- 

 cante, Spain. The trees, which were 20-25 years 

 old at the time of the experiment, had been 

 previously manured merely with the ashes of 

 the husks. Three plots in all wore taken aud 

 while one was left unmanured and another 

 received Superphosphate, 330 lb. per acre, aud 

 Nitrate of Soda and Sulphate of Ammonia each 

 80 lb. per acre, tho other plot got the same 

 quantities of the last-mentioned materials and, 

 in addition, a dressing of Kainit at the rato of 

 450 lb. per acre, that is a " complete manu- 

 ring." The Superphosphate, Sulphate of Am- 

 monia and Kainit were applied round the base 

 of the trees on the 5th December, 1907, and the 

 Nitrate of Soda in the following spring, one 

 half in March and the other half in May. The 



harvest took place on the 28th August, 1908, and 

 the results may be represented as follows : — 



•2 w .2 a 



o 3 



Is.! 



I. Unmanured 



II. Incomplete manuring 



(without potash) 

 330 lb. Sup.'.rphoaphate 

 80 1b. Nitra te of Soda 

 80 lb Sulphate of 

 Ammonia 



III. Complete manuring 

 330 lb. Superphosphate 



SO lb. Nitrate of Soda 

 80 1b. Sulphate of 

 Ammonia 

 150 lb. Kainit 



1,532 1,009 



Comment on these results is needless. They 

 testify clearly enough to the practical im- 

 portance of restoring to the soil in the culti- 

 vation of the almond the three chief ele- 

 ments of plant food— Nitrogen, Phosphoric Acid 

 and Potash. 



GEORGE A. COWIE, m.a., b. sc. 



CLEAN-WEEDS^Q RUBBER ESTATES. 



May 14th. 



Dear Sik, — A good deal has been written on 

 the subject of clean-weeding rubber estates. 

 Both those iu favour of, and against the system 

 have much to say in support of their convictions 

 which deserves serious consideration. But 

 what the rubber planter wants is the ultimate 

 analysis of tho whole question. Personally, I 

 lind that clean weeding tends to promote 

 greater growth of the tree, and this is generally 

 acknowledged. If exposure of the soil results 

 in surface deterioration, it obviously does not 

 affect the plant injuriously, while the decidu- 

 ous character of the Para rubber tree would 

 seem to prevent impoverishment of the soil. 

 Then again, clean weeding is only necessary 

 during the first few years of the life of an 

 estate, i.e. until the branches of the tree afford 

 over-head shade. If, therefore, the planter 

 tinds that clean weeding helps the tree to grow 

 more quickly, returns on his outlay are sooner 

 realisable. This is a consideration not to be 

 neglected unless it can be conclusively proved 

 that clean weeding during the earlier years of 

 the existence of a plantation affects it injuri- 

 ously later on. 



I have adopted a system of clean weeding 

 along the lines of the trees, and at right angles 

 to the slope of tho ground, which seems to me 

 to servo several useful purposes. The root 

 areas of the trees are kept free from noxious 

 weeds, and light and air are freely admitted. 

 The cleared strips form paths which facilitate 

 inspection of tho estate, and the uncleared 

 strips of scrub between the lines of trees pre- 

 vent wash and thus save the expense of drains, 

 whilo affording protection to the young rubber 

 against wind. 



" HEVEA BRASILIENSIS." 



