September, 1911.] 



199 



Saps and Exudations. 



as flint and heavy as lead formed under 

 enormous pressure, to the light and 

 friable scoria which can almost be 

 crushed in our hands, and the trans- 

 formation from the immense houlder to 

 smaller and smaller rocks until the rock 

 soil— the base of all soils — is formed, 

 takes place almost before our eyes. 



"The process of disintegration may 

 be greatly hastened by cultivation. 

 Anything that will stir the rocks and 

 break or chip off small portions from 

 time to time makes it easier for the 

 rootlets to enter the pores, and so 

 hurries along the disintegration and 

 decomposition. 



"On such soils as these ordinary 

 methods of culture have to be abandoned ; 

 add to this fallen trees lying all over 

 the fields, and culture as generally under- 

 stood becomes impossible ; all that we 

 can do is to keep down the weeds and 

 clean around the trees while they are 

 young; in this we have derived great 

 benefit from a suggestion of Dr. Wilcox — 

 the arsenic spray. This is a solution of 

 arsenic and washing soda dissolved in 

 water by boiling, and applied by force 

 pumps in the form of a fine mist ; it will 

 not take the place of cultivation, but is 

 a valuable auxiliary. 



"We have found that on our lands 

 the best and cheapest method is to 

 leave all the debris on the field to rot 

 back into soil ; it keeps down the weeds 

 and adds to the humus ; it must, of 

 course, be laid in windrows, and gradu- 

 ally pulled together as portions of it 

 disappear ; two or three years tell the 

 tale. If the land is planted as soon as 

 cleared of forest — and no other method 

 should be adopted— there will be nearly 

 a year in which no great expense for 

 weeding will be required ; but sooner or 

 later the weeds creep in, and then if the 

 trees have not made a good growth in 

 the meantime, the trouble and expense 

 commence. Intercrops may be called 

 to our assistance for the first two years ; 

 after that they will have to be aban- 

 doned to a great extent, as the roots of 

 the two crops will have interlaced and 

 both will suffer. Our best soils, our 

 arable land ! Sand and volcanic ash 

 saturated with humus and thoroughly 

 pervious to air and moisture require 

 less cultivation than more compact 

 soils ; even here, however, a thorough 

 stirring produces new combinations ; 

 new supplies of food are presented to 

 the innumerable bacteria, and they in 

 turn produce large supplies of soluble 

 food material for the trees— which 

 promptly respond to it — and if fertilizer- 

 is liberally supplied in addition at this 

 time, two or more years' growth may 



be condensed into one. This requires 

 money, and men ! — but it is money well 

 and wisely expended. 



" Fertilizing is a necessary part of 

 cultivation ; it reduces the expense of 

 weeding, not by eradicating the weeds, 

 but by hastening the growth of the 

 crop; two weedings with fertilizer will 

 bring the trees to the same size as three 

 or more without it ; it gives them in- 

 creased vigour, and makes them better 

 fitted to withstand unfavourable con- 

 ditions later on. We have found that 

 from one-half to one pound, applied 

 around the tree, gives good results, and 

 that two applications are better than 

 one, even if only the same amount of 

 material is used. As to the kind— any 

 good, complete fertilizer will work well, 

 and the higher grades are the cheaper, 

 as the cost of transportation is pro- 

 portionately less. The best proportions 

 of the phosphates, nitrogen and potash, 

 will have to be matters of experiment; 

 analysis of the soil cannot be entirely 

 relied on ; there is in all probability 

 vastly more of each in the soil than you 

 are likely to apply, and it is safe to say 

 that if leaching or washing out can be 

 avoided none of the material will be 

 wasted. 



" We have found that a heavy growth 

 of weeds even in the middle of the lines 

 is better avoided ; that by cutting every- 

 thing down there was a great and imme- 

 diate improvement in the trees. Weeds 

 choke the tiny feeding roots, and by 

 forming a sod prevent the air from 

 entering the soil ; this is doubly true of 

 Hilo grass ; unless this latter is kept 

 under control the inevitable result with 

 the rubber tree, as with most other trees 

 or plants, is loss of vigour, deterioration, 

 and eventually death." 



Discussion. 



Mr. Ewart : Do you fertilize all the 

 trees ? 



Mr. Turner : No ; just the younger 

 trees. There is no question whatever 

 about the value of the fertilizing. 



Mr. Ewart : What kind of fertilizer do 

 you use ? 



Mr. Turner : Just the ordinary ferti- 

 lizer of a high grade. The fertilizer 

 that we use was prepared especially for 

 us by the Hackfield Fertilizer Works. 

 The formula comes from a California 

 fertilizer man, and was given to me as a 

 matter of good will : 10% ammonia from 

 nitrate, 8% to 9% of phosphate from 

 steel bean, 5% muriate of potash. I 

 have never used any straight potash. I 

 used it on one tree and killed the tree. 

 It was a small tree, and I put it on 



