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where the soil is stratified, I have found that the roots penetrate 

 much deeper in order to reach the water supply. Laboratory 

 experiments have shown me that roots of Castilla seedlings in 42 

 days have grown to a length of 3 feet 4 inches in order to reach 

 a water supply, which by mechanical arrangement was gradually 

 distanced from the roots in proportion to their growth. In the 

 same time roots of Castilla seedlings in the undisturbed soil on 

 Zacualpa did not reach a greater length than 8 inches. A few 

 years ago the land was covered with a layer of ashes through the 

 eruption of a neighbouring volcano, Santa Maria, just across the 

 Guatemalan line. These ashes have formed a cover over the ground 

 which materially assists- in checking evaporation. The fertility 

 of the soil is not unusually high, so that we may in time have to 

 apply fertilizers. Experiments are now being conducted to 

 ascertain the results of manuring this soil for rubber. The soil 

 is rather poor in nitrogen and it has been found that the growing 

 of leguminous plants between the rubber trees markedly influences 

 the development of these. 



If I add that the plantation is comparatively little exposed to 

 high winds I have shown some of the reasons why I consider the 

 natural conditions of this place nearly ideal for Castilla planting. 



The method of planting first employed was to sow the seeds in 

 nurseries, and when the seedlings were 4 to 6 months old they 

 were transplanted. Very often, however, transplanting was not 

 done before a year after sowing. The plants were then from five 

 to twelve feet high. The seedlings were cut 5 or 6 inches below 

 the surface, and topped, leaving a pole some 3 feet long. Tied 

 into bundles, which were packed on mule back, these poles were 

 carried to the field. With a pointed stake, holes were made in 

 the ground about one foot deep, the pole placed in the hole and 

 the soil pressed close to the stem. When this planting was done 

 carefully and if rain fell within the next two or three days not 

 more than 3 or 4 per cent, of failures occurred. In places where 

 the soil was somewhat sandy the failures were more frequent. On 

 Zacualpa as many as 1 8,000 trees have been planted per day in 

 this manner. At first it was believed that shade was necessary, 

 but it was soon noticed that this idea was erroneous and a 

 system of planting in semi-shade was adopted. When clearing 

 a certain amount of high forest trees were left standing, about four 

 to the acre. It is now demonstrated, however, that even this 

 amount of shade is too much on Zacualpa. On the other plan- 

 tations, however, Juilapa and Zacualpa II, this semi-shade is 

 beneficial as it assists the young plants through the dry season. 

 These plantations are situated at a somewhat higher elevation, 

 and the land is undulating and more drained. 



Later experience has proved that the cheapest and surest method 

 is to plant the seeds at stake. Nearly a year's growth is thus 

 gained, and it does away with the expensive replanting where 

 failures occur under the transplanting method. The seeds are 

 planted in small hills, about seven seeds in each hill, three inches 

 between the seeds. The hills are at a distance of about seven. 



