COCONUT PLANTER'S MANUAL. 101 



cheaper mineral manures such as hasic slag and potash, or mulching with 

 any weeds or cheddy, all have a good effect on the palms, and increase 

 the yield considerably. Such treatment is within the reach of every one, 

 and should well repay the extra trouble and slight expense incurred. 



Mr. Petch has shown that on coconut trees examined at Poradeniya the 

 fertilisation of one inflorescence by another on the same tree would 

 only he possible when a new inflorescence appears within 3U days of the 

 former one and that this only occurs in May, September and October, 

 which arc u ually the most active growing periods in Ceylon and the tropics 

 generally. The duration of the period that the female flowers are opening 

 depends on the number on the inflorescence, 2 or 3 opening daily, but the indivi- 

 dual female flower is only receptive for 24 hours or less, from 3 to 4 weoks after 

 the opening of the inflorescence. It is possible that the larger crops in 

 May- ' uly are due to this overlapping and fertilisation on the same tree, but 

 more probably to the increased vegetative activity at that period of the year. 



A badly yieding troe, however, can be made to yield more heavily by 

 cultivation and manuring, though whether the effect is to increase the 

 number of female flowers on the newly forming inflorescence, or to cause 

 more rapid floral production, within the 30 days necessary for fertilisation 

 on the same tree, or the prevention of falling-off of immature nuts has still 

 to be determined. 



Little is yet known as to the effect of any of the principal manuring 

 constituents, such as nitrogen, lime, potash and phosphoric acid on the for- 

 mation of a larger proportion of female flowers on each flowering stalk, or 

 whether moisture alone or in conjunction with one or more of these is the 

 chief cause. The actual formation of the enbryo leaves and flowers in the 

 growing apex of the palm must take place some months before they actually 

 appear, and it is of importance to ascertain what are the determining factors- 



The manuring experiments which are being canied out in difl'erent 

 coconut districts should enable this and several other questions to be solved, 

 but careful records for several years must be kept before definite conclusions 

 can be drawn, excepi on points of actual manuring for crop, which should 

 be available in 3 or 4 years. 



Much has already been learned by practical experience from manuring 

 experiments on a large scale conducted by Mr. A. £. Kajapakse and others 

 and the thanks of all coconut planters are due to these gentlemen who have 

 allowed their experiences to be published for the benefit of the community. 



If similar data of the practical experience of coconut planters were 

 collected and the results condensed for publication in their annual report, I 

 am sure that the Agricultural Department would gladly assist in making 

 the deductions. 



In starting any new experiments, it is important that each is made to 

 determine one point only, and that dates, number of trees, climatic con- 

 ditions and all factors likely to affect the result are carefully recorded, 



