Vol. XIII. No. 329. 



THE AGRICULTURAL NEWS. 



395 



STUDENTS' CORNER. 



THE VALUE OF LEGUMINOUS GREEN 

 DRESSINGS. 



In thf last number of the Agricultural Nemi attention 

 was directed to some leguminous crops as a possible source of 

 hay. The agricultural student might pay attention to this 

 class of plants for several other reasons. The leguniinosae 

 afford the very best material for green dressing. But the 

 fact obtrudes itself upon the observer that every legume 

 does not produce identical results in every locality. For 

 instance, the cowpea ( Vigtia uvrfuicnlata) .seems to be so 

 attackad by caterjiillars in Antigua, as to have been 

 abandoned as a green manure crop, although in other islands 

 it has proved to be eminently adapted for this purpose. 

 It is the same case with other crops of this class. One 

 planter will extol the virtues of pigeon peas (Cajanus indicus), 

 another tells you that nothing can be better than horse bean 

 (Canavalia eniiforiids), some one else advocates woolly pyrol 

 (Pkaseolus munyo), while still another assures you that 

 Barbuda bean (Pkaseolus lunatus) is the one and only green 

 leguminous dressing. And probably, in a sense, each one is 

 right, because the crop he advocates has been proved, experi- 

 mentally, best suited for the locality and conditions he has 

 to face. Here then is scope for the student's observations 

 and notes. Carefully observe which leguminous crop 

 succeeds best, and gives the largest green crop in your own 

 neighbourhood. Note any reasons to which you can attribute 

 this comparative success. For instance, one legume may 

 succeed best on a heavy .soil, while another is a comparative 

 failure, though giving a fine return on lighter land. (Jr one 

 may have a much greater drought-resisting capacity than 

 another, and so do better in drier islands. 



Another point for noting is the liability of any species 

 to insect attack. Here may be noted \vhat caterpillars attack 

 each sjjecies, and whether the use of insecticides could 

 feeneticially be resorted to without damage to the plants; 

 whether also the use of insecticides would be economically 

 advantageous. In this connexion, of course, will be noted 

 if any scale in.sects infest the plants, and the identification of 

 them should be attempted. By such observations as these 

 the student gains real knowledge of his crops, and can give 

 reasons for his operations. He can say that he plants such 

 a legume as a green crop in preference to such another, 

 because of facts which he knows, and not merely because he 

 has been advised to do so by someone 'else. 



While making observations on green manure crops, 

 experiments, even on a small scale, might be made on lines 

 suggested by those carried out at Pusa, in India, as outlined 

 in the A;irindtural Neirs, November 7, 1914, p. 361, as 

 to whether the value of green manure is not increased by 

 a partial maceration before application.' 



The student of course knows that one great benefit 

 that the growth of a leguminous crop bestows on the land is 

 the increase of nitrogen in the soil. The roots of each 

 species that comes under the student's observation can be 

 examined for the characteristic nodules. This can be done 

 with a magnifying glass of no very great power, and in many 

 instances with the naked eye. The number of nodules per 

 plant at corresponding periods of growth, might be recorded 

 as a useful index of its value in tljis respect. The soil 

 conditions materially affect this factor, so such conditions 

 ought to be noted at the same time. It cannot be too 

 strongly put that the Ivabit of observation and reflection on 

 all phenomena, is the way for the student to gam increased 

 knowledge, and that knowledge is real power, in agriculture 

 as in every other walk of life. 



Co-wpeas and Maize for Fodder.— An experi- 

 ment conducted in the south coast district of New South 

 Wales with a mixture of cowpeas and maize as a fodder crop, 

 reported in the Agricultur'tl Gazette of New South Wales, 

 September 191-f, would seeiu to be instructive to West Indiair 

 planters. 



For sowing, a mixture of 5 tt). of cowpeas and 20 tt). of 

 yellow dent corn per acre was used. The idiots gave excellent 

 results. Cowpeas are excellent drought resisters, and they 

 made in every case splendid growth, climbing to the top of 

 the maize stems, and forming a dense growth at the base. 

 On one of the plots the yield was over 22 tons per acre. The 

 growing of cowpeas with maize for fodder is strongly advised, 

 not only because they grow well together, but also because 

 they greatly enhance the food value of the fodder, whether 

 used green, or made into hay. 



Germicides, Disinfectants, Antiseptics, and 



Deodorants. — 'Considerable confusion exists in the popu- 

 lar mind regarding the meaning of the above terms. ■ To 

 many they signify one and the same thing, as a result of 

 which numerous worthless preparations with a disagreeable 

 odour, but otherwise harmless, have been employed in the 

 destruction of disease germs without avail. 



'The terms germicide and disinfectant may be used 

 synonymously to designate anj' agent which has the power of 

 destroying germ life, such as sunshine, heat, carbolic acid, 

 lysol, bleaching powder, corrosive sublimate, and formalde- 

 hyde gas. An antiseptic is something which merely prevents 

 the further growth and develr>pment of micro-organisms 

 without necessarily killing them: for example, alcohol, biiric 

 acid, listerine, hydrogen peroxide, and most of the common 

 disinfectants in dilute sijlutions. A deodorant may be said to 

 be anything possessing an odour more pronounced and 

 jjenetrating than the odour which it is intended to modify i)r 

 cover up. It does not posse,s.s, necessarily, either germicidal 

 or antiseptic properties, and depends for its efficiency simply 

 upon producing one odour to mask another. Many of the 

 best germicides are also splendid deodorants, but deodorants 

 are not generally germicides.' [Modern Farming, (Jctober 

 5, 1914.) 



A Disease of Poultry, which is known as fowl yaws 

 in the West Indies, appears first as an affection of the skin, 

 producing pustules on the comb, wattles, and face of the birds. 

 Unless checked, the disease seriously affects the mucous mem- 

 l>ranes, and not uncommonly results in death. In Bulletin 

 240, .June 1914, of the Agricultural Experiment Station of 

 the University of Wisconsin, there is a notice of experiments 

 made with a new vaccine treatment of this disease, known as 

 chicken pox, or sore head, in the United States. Vaccines 

 were prepared by grinding diseased tissues, such as the pox 

 scabs and affected membranes, and subjecting them to a tem- 

 perature of 131° F. for one hour. The injection of this 

 vaccine into healthy, as well as into infected fowls, was found 

 to be very Ijeneficial. When injected in the initial stages of 

 the disease, the vaccine apparently had the effect of rendering 

 the attack milder, and the recovery more rapid. Of four 

 hundred and forty healthy fowls treated by a double vaccin- 

 ation, with an interval of five days, only four subsequently 

 developed the disease; while of seven ty-tive un vaccinated 

 controls, twenty-six showed marked signs of the pox in the 

 three weeks of observation. The natural susceptibility of 

 birds to infection varies; yet vaccinated liirds placed in in- 

 fected pens escaped the disease, while it was possible to infect 

 some of the controls. Further investigation is looked for. 



