394 



THE AGRICULTURAL NEWS. 



Decembee 2, 1916. 



ROOT SYSTEMS AND LEAF-AREAS OF 



CORN AND THE SORGHUMS. 



It is well known that the Sorghums, for example, 

 Guinea corn (S. vulgare), withstand severe climatic 

 conditions better than Indian corji (Maize). Experi- 

 ments have been conducted in the United States to 

 determine the fundamental characteristics of sorghum 

 plants that enable them to do this. The experiments, 

 which are described in the Experimevt Station Record 

 (Vol. 3.5, No. .5), had particular reference to differences 

 in root systems and leaf-areas. 



In all stages of growth the primary root systems were 



found equally extensive, but the secondary roots of the 



sorghum plants as compared with those of corn were twice 



as numerous per unit of primary root. Both primary and 



secondary roots of the sorghums were found to be more 



fibrous than those of corn. A study of the weight of the 



dry matter of the aerial portions and of the roots of mature 



plants showed an average ratio of the dry weight of the 



grain, stem, and leaves of standard Kafir to the dry weight 



of the roots of 1-5:1 and U-9:l in 1914 and 1915, 



respectively, while the dry weight of the .stem and 



leaves of the same plants was, on the average, 109 times 



that of the root weight in 1914 and lO'l times 



the root weight in 11)15. The average ratio of the dry 



weight of the aerial portions of Dwarf Milo maize to the 



weight of the roots was found to be 157:1 in 1914 and 



15:1 in 1915. The weight of the stem and leaves of the 



same plant was 9-6 times and 8 times, respectively, the 



weight of the roots for the two years The weight 



of the stem and leaves of Pride of Saline corn was 



9-6 times the root weight in 1914 and 78 times the weight 



of the root system in 1915. The aerial parts of dwarf 



Blackhull Kafir corn in 1915 showed a weight of 157 times 



that of the roots, and the weight of the stem and leaves 8'9 



times the weight of the roots. The results of experiments 



regarding soil moisture content and depth of root penetration 



seemed to show that under the existing conditions very 



little, if any, depletion of soil moisture took place below the 



depth of root penetration. 



The leaf area of the corn plant at all stages of its growth 

 was found to be approximately twice asgreaias that of Dwarf 

 Milo maize, and never less than 1'5 times that of Blackhull 

 Kafir corn. It was pointed out that the sorghunis would 

 have the advantage over the corn plant under any. clioa^atic 

 condition tending to bring about a loss of water froiH the 

 I)lants. The two sorghums as compared to the corn plant 

 have only one-half the leaf surface exposed for the evapo- 

 ration of water, and idso have a root system which, 

 judging from the number of secondary roots, would be twice 

 as etlicicnt in the absorption of soil moisture. 



These results are of great interest. Similar experi- 

 ments with varieties of sugar-cane resistant and sus- 

 ceptible to drought, would constitute a useful piece of 

 work that might be conducted in the West Indies. 



TESTING OF OIL-BEARING NUTS IN 



THE PHILIPPINES- 



Investigations have been made by the Philippine 

 Bureau of Science concerning the qualities of the calumpang 

 nut, which has been found to be (idible, though slightly 

 purgative when eaten in quantities. The composition of the 

 nuts, as annlysiid by the Bureau of Science, is: fat (by 



extraction of dry seeds), 51-78 per cent.; protein, 21 '61 

 per cent.; starch, 12'10 per cent.; sugars 5 per cent.; cellulose, 

 etc. (by difference) 5'51 per cent.; ash, 390 per cent. 



The oil expressed from the calumpang is sweet, with 

 a comparatively high melting-point. Its colour is a light 

 yellow. One chemist reports that it appears to resemble 

 olive oil very much in its physiological action. It is non-toxic, 

 and has no irritating action. It can be used in the same 

 manner as olive oil, and should be especially Hseful for 

 culinary purposes. 



Additional facts, writes the correspondent at Manila of 

 the United States Department of Commerce, have also been 

 ascertained concerning the oil-bearing nut, Chuochiton ciimin- 

 (/ianiiit, Harms., in recenj. invesiigations by local .scientists. 

 The plant belongs to the natural family in which the 

 Philippine santol occurs. The nut is known in many parts 

 of the island.s, from northern Luzon to southern Mindanao. 

 The name applied to it in Catnarines and Laguna, 'bilu- 

 canag', is taken to indicate that the natives recognize the 

 nuts as oil-bearing, for the same name is applied to another 

 and well-known oil-bearing nut, although the two are not 

 alike in any other particular. 



The C/dsochilon cuiaingianus. Harms., is described as half 

 ellipsoidal in shape, when fresh, and as averaging 3 centimetres 

 (118 inches) in length, and 25 centimetres in width at the 

 widest portion. The shell is rather hard, constituting about 

 (lO per cent, of the total weight, and it is difficult to separate 

 it from the meat. In a quantity of shelled nuts tested by 

 the Bureau of Science, which used petroleum ether for the 

 purpose, about 31 per cent, of the whole nut was a reddish- 

 brown oil. The composition of the dry kernels was found to 

 be as follows: fat (by extraction), 44' 12 per cent.; protein, 

 9 per cent.; ash, 3' 19 per cent. 



The dry kernel yielded 3530 per cent, of oil on expres- 

 sion. The oil had a rancid odour, and was non-drying. On 

 experiment it was found to have purgative properties. This 

 oil, however, was found to have a weaker laxative effect than 

 castor oil, 5 pirts of it being approximately equivalent to 

 1 part of castor oil. This oil, more commonlj' called cato, 

 was found by the Bureau of Science to be valuable for soap- 

 making. One local firm now employs the oil in that industry, 

 {Journal of the Royal Sucieli/ of A rtf. ) 



Improvement of California Orange Groves.— 



Owners of the largest orange groves in Southern Cali- 

 fornia have already adopted the plan of keeping a record 

 of the performance of each individual tree, and eliminating 

 any trees that do not prove to be good producers, usually by 

 top-working them with Select buds. So far, however, it has 

 not been found possible to get many ol llie owners of small 

 groves to adopt this process. The California Fruit Growers' 

 Exchange is now |)lanning to assist the growers in securing 

 the record of trees in these small groves, taking advantage 

 of the fact that small growers do not pick their own fruit, 

 but entrust the task to the local association of the exchange, 

 which sends out a trained gang of men to pick the fruit. It 

 is now pro|)osed to add- to eiich i)icking crew a man who.se 

 duty will be to make a record of the production of every tree; 

 and this report, furnished to the owner of the grove, will 

 enable him to supplant the bad yielders with trees of a better 

 strain, in many cases by top-working the drone or undesirable 

 individual tree. The exchange has for -several years been 

 working on the standardizing of the citrus 'pack'; aco-operative 

 and organized effort is now being made to stsindaidize the 

 'production'. {The Journal nj Hireility, Xoveinber 191(;.) 



