Avavsr i, iSSa,] 



THE TROPICAL AGRICULTURIST. 



1^5 



FODDER PLANTS. 



Tagasaste {Cytisvs proUfertis), Adelaide, 



Dr. Schombm-gh reports: — "The eeeds have grown 

 uncommonly well, tlie plant rebelling a height of 

 four to five feet. There is not the slightest doubt 

 that this plant delights, not alone in our climate, 



but in any kind of soil and .situation I do 



not doubt a moment that this shrub, if sown on the 

 sheep-runs, naturally well covered with soil, will soon 

 become acolimntised, and will stock the runs with a 

 new fodder plant. " 



Brisbane.— In tlle^e gardens the seed germinates freely 

 in the open air. but makes but little progress iu its 

 subsequent growth. 



Tcoxinte {Euchlana luxurians), Adelaide. — Dr. Schom- 

 burgh reports: — "I have now cultivated it for the 

 last three years, and no doubt it is one of the most 

 prolific fodder plants. Notwithstanrling t!ie prevail- 

 ing dryness of the two last summers, the hot wind.? did 

 not injure it, the plants not showing the slightest 

 effect on their leaves, which preserved their healthy 

 green, while the bludes of the other grasses suffered 

 materiallvi The habit of throwing out young shoots 

 is remarkable, to the number,, in some plants, especi- 

 ally such as stand in a moist situation, of 50 to 60, 

 with a height of five to six feet. There is one draw- 

 back. The plant, as I have already remarked, bi-iug 

 essentially tiopical in its habits, the ripening of the 

 seed-crop wilt be problematical with us, as early 

 frosts will kdl the plant. " 



Jamaica. — Mr Morris reports : — Treated as a garden 

 plant, the Euchlmim has grown well at Castleton 

 gardens, but sufficient experience has not yet been 

 obta'ned to express an opinion whether it will prove 

 generally Buitable as a fodder-plant. A good crop of 

 eeed has been harvested and widely distributed for 

 experimental purposes in dift'ereut parts of the island. 



Madras. — The Agri- Horticultural Society report : — 

 " Eadikena {Reana) luxurians continues to grow lux- 

 uriantly, seed, and reproduce itself, with so little care 

 and watering as to confirm the opinion expresssd in 

 last annual report, that it may be considered a suc- 

 cess. It is particularly worthy of growth in private 

 garden?, a few stalks of it giving a green bite to horses 

 in the long dry weather, when change of food is eo 



hard to get As a single crop, with a given 



quantity of water and moderately good soil, the 

 Reana will produce, in hot weather, a much givater 

 bulk of green fodder than either lucerne or guinea- 

 gras?, which are most commonly grown iu Madras for 

 the purpose. ' — Jounuil of the Society af Arts. 



4 



LOSSES OF NITROGEN BY NITRIFICATION IN 

 SOILS. 



According to Mr. Lawes, the amount of nitrogen 

 carried through the soil by the rainfall, or rather 

 washed out of it and discharged through the drain 

 pipes, ia very great. The extent to which the evil 

 is considered to work will be readily seen by the 

 perusal of a lecture of Mr. Warington which was 

 inserted iu 27ie FieU of the 25th ult. — one which 

 will attract all the more attention from the fact that 

 Mr. Warington is associated with Mr. Lawes and 

 Dr. Gilbert in making those particular experiments 

 at Rothamsted on which the conclusion has been 

 founded. 



Mr. Warington read a piper on the subject at a 

 meeting of the Society ot Ans f n the 23rfl ult., and 

 after alluding to the evidence of the draiu-^auge, wnich 

 was clearly shown by a large cliagr-m ;ip;;en led to 

 the wall, stated that the fi^ld at Kothara-ted, which 

 is laid out in experimei.tal plots, has a drain pipe 

 at 2 ft. deej) under every plot, ami that an examin- 

 ation of the drainajje water from these pipes not only 

 15 



I confirmed the evidence derived from drain g.auges, but 

 sliov\ed that wht-n salts of ammonia are applied as a 

 dressini; in the autumn, the process of nitrification in 

 the soil has the effect of rapidly cinvertiug the am- 

 monia into nitrates, to be washed out by the first 

 heavy rains. In one case he siid a distinct increas3 

 of nitric acid in the drainage water was trac-d to 

 the ammonium salts within forty hours after their 

 application, an i he thought that the whole of the 

 ammoni'i contained in them might be nitrified anfl 

 become lost within a month after appUc;itiou. 



In the discu'siou which took place after the lecture 

 at the meeting of the Society of Arts, Mr. Darby 

 called attention to the fact that this conclusion was 

 diametrically opposed to the views taken, some twenty 

 years since, by Professor Way, who made the dis- 

 covery that the silicates in the soil have the power 

 of arresting and absorbing ammonia whenever coming 

 in contact with it. Nor was this all that he con- 

 sidered he had ascertained ; for iu one of his papers 

 in the "Royal Agricultural Society's Journal ' he 

 seemed very positive that the silicates would retain 

 with a very tight grasp the ammonia thus attracted. 

 Mr. Darby thought the Rothamsted experiment, on 

 which the speedy conversion of ammonia into nitric 

 acid had been based, would have been more conclus- 

 ive if the depth of the drains from which the 

 discharge had been tested had been three feet instead 

 of two feet; and staled that the clear, pure appear- 

 ance of drainage water, when discharged from deep 

 drains, bad hitherto prevented the opinion being held 

 that it contained nitrogen in considerable quantity ; 

 and further, he asked if it were uot possible . that 

 the principle of nitrilication had mure powerful action 

 iu the land at Rothamoted than it would have in 

 soils in general. 



Dr. Gilbert, who was in the chair, alluded to 

 these several points, but gave most prominence to 

 the apparent purity of drainage water to the eye 

 beincr no evidence, as it had been proved that when 

 mo-t clear and sparkling itcontdns a la'ge quantity 

 of nitric acid. As to the character of the both imsted 

 soil he considered it neither very fertile nor very 

 poor naturally, and rather heavy than light; con- 

 sequently he tbnnglit it must be considered of a 

 fair average for test purp ises. The silicates he con- 

 sidered would be very likely 1 1 attract ammonia by 

 decomposing it::: base, but the experiments at Piothamsted 

 proved that they ri-taiued it but a short time. 



Mr. Warington, in his replv, admitted that the 

 drains in the experimental field at Rothamsted would 

 have been better for the test of the drainage water 

 had they been jjlaced 3ft. deep ; but said that the 

 draining was effected as far back as 1849, when the 

 system of shallow drnining, introduced by Mr. Smith, 

 of Di-anston. was commonly practised. It may be 

 rem.arked as rather singular that neither Dr. Gilbert 

 nor Mr. Warington alluded to the point which had 

 been raised as to the possibility of the Rothamsted 

 soil having the nitrifying principle in excess, as on 

 it seems to turn the pivot of the entire inquiry. 



The following ex'racts from Professor Way's writings, 

 to be found iu Vols. 11 and 13 of the "Royal Agri- 

 cultural Society's Journal " show plainly enough what 

 hi* oijinions were. He says : — 



It has been shown that ordinary soi's possess the 

 power of separating from soluiion and retaining for 

 the purposes of vegetation the bases of the different 

 alkaline salts and certain animal and vegetable sub- 

 stances, and thiit this power extends to all those 

 substan 'es to which we attach the most v.ilue asmanure. 



In Vol. 13 of the "Royal Jourual " th- same view 

 is still more fully enlarged upon as fo lows : — 



It has long been known that soils a-quire fertility 

 by exposure to the influences of the atmosphere — 

 hence one of the uses of fallows. It has also been 



