434 



Another point of interest, so far as these experiments go, is 

 in favour of tappings during November, December, and January 

 which may or may not be quite natural. If the lactiferous system 

 of a Para Rubber tree has no other function than that of sealing 

 wounds, why there should be an increment of yield during these 

 months is not evident, but if some reserve material necessary for 

 the fruiting season which immediately follows is called upon, the 

 increase of latex may be quite natural. 



This brings us to the point that in a natural state, i.e., with 

 trees which have not been regularly tapped, some months are 

 more favourable for tapping than others, and the same remark 

 applies to the growth of new bark. Trees tapped late or early in 

 the year are the slowest to recover. The resting period, when the 

 tree is deciduous, or partly so, usually commences in February, 

 and from then until the end of June when the fruit commences 

 ripening, we have not been satisfied with tapping trials ; but we 

 digress to point out that while young trees are uniform in their 

 flowering periods, older trees become variable and it is quite com- 

 mon to see one half of a tree deciduous or wintering while the 

 other half is verdant green. This may account for some of the 

 vagaries of the tree, of which few other trees represent so many. 

 Indeed, with this species it is difficult to establish any point with- 

 out an exception. It is therefore possible that periodical tappings 

 would even bridge over these dormant months for we know that, 

 up to date, the same trees tapped this year as last at the Botanic 

 Gardens shew an increment of about 45% for the reason that we 

 suppose, the trees had been previously tapped and are singularly 

 responsive on further tapping. 



A further point of interest as shewn by these experiments is 

 the ratio of yield to the size of the tree, here however we except 

 the age of the trees, which in respect of size vary from under 2 

 feet to over 6 feet in girth. Following what has been already 

 stated that these experiments do not go beyond the compartive 

 yield by different methods we find the following table may be drawn 

 up :— 



Girth at 3 feet from 



GROUND. 



Comparative yield per inch of girth 

 at 3 feet from ground. 



Under 2 ft. girth 



Under J oz. 



From 2 ft. to 2 ft. 6 inches ... 



i oz. 



From 2 ft. 6 ins. to 3 ft. 



Under § oz. 



From 3 ft. to 3 ft. 6 ins. 



J oz. 



From 3 ft. 6 ins. and over 



Over J oz. 



