V«L. XV. No. 3.59. 



THE AGKICULTURAL NEWS. 



37 



The shade plants attained a nearly unifurm lieight ni 

 G feet 10 inches, while the height of the sun plants averaged 

 about 5 feet 9 inches. The leaves of the shade planis were 

 much larger and thinner than those of the sun i)laiits, and the 

 internodes of tlie stem were longer. In sixty days the plants 

 in the open transpired an average of 4.5'539 litres of water 

 per plant, and required 211 •J'i c.c. of transpired water per 

 gram of water-free substance produc-ed, while the corres- 

 ponding figures for the shade plants were 3-5 '2 12 litres, and 

 186-90 c.c. The sun plants thus transpired, on the average, 

 about 30 per cent, more water per plant than the 

 •shade plants, while the average weight of dry matter 

 produced was, in the mature plants, nearly the same 

 in both sets. It follows that the series h»ving the 

 higher total transpiration also has the highest transpiration 

 jier gram of dry plant substance. This is corroborated by 

 the above figures. The quantity of water transpired per 

 unit of dry matter produced is remarkably uniform for the 

 plants within each group. This confirms the conclusion that 

 under the siiiie aerial conditions the cjuantity of water 

 transpired per unit of dry matter }iroduced is constant, and 

 independent of the nature i)f the nutritive solutions or of 

 their concentration or of tlie state of development of the 

 plant. 



After a discussion of the observations and opinions of the 

 most com[)etent authorities on the subjec: of the relation 

 between tnuispiralion and production of plant substance, the 

 writer draws the following conclusions: — 



Under the climatic conditions of Western Cuba the 

 transpiration of tobacco plants grown in the open ground is 

 nearly 30 per cent, greater than that of plants grown under 

 the cheese cloth shade commonly used for shading tobacco 

 in that region. The transpiration per unit area of leaf 

 .surface is nearly twice as great in the sun plants ns in the 

 shade plants. 



The shading of tobacco plants by this grade of cheese- 

 cloth does not seein to result in a diminished production of 

 total plant substances by the shaded plants, as compared 

 with other like plants not shaded. Since, however, the leaves 

 of the shade-grown plants have a nmch greater total area 

 than those of the j>lants growing in the open, it is evident 

 thit the quantity of plant raiterial elaborated per unit of leaf 

 area is greater in the plants grown in the open. 



Although the total production of dry plant substance is 

 not influenced in any marked degree by the cheese-cloth 

 shade, the distribution of this substance is affected in such 

 a manner tint in the shade-grown plants relatively less 

 material is deposited in the leives and more in the stems 

 than in the corresponding organs of the plants grown in full 

 light. No evident influence is e.xerted on the deposition of 

 material in the roots. 



YEAST-FODDER. 



Dr. Prinsen Geerlig.s, in recent letters to the 

 Louisiana Planter, has made reference to the new 

 German process of making albtitninoids from sugar and 

 salts, chiefly ammonium sulphate, by the action of 

 yeast, which fact is considered ais a great assistance 

 for the cattle bri'eders in times when the supply of 

 maize, bran, oilcake, etc., from overseas, is stopped by 

 the blockade. In the issue of the above journal for 

 October 9, Dr. Geerligs deals with the subject in consi- 

 derable detail. He says: — ■ 



The German Government has seized the various patent 



rights for the manufacture of yeast-fodder, in order to monop - 

 olizo the stocks of that commodity, and to distribute the 

 stutt' among those who want it. It appears, however, that 

 this method of manufacturing albuminoids on a commercial 

 scale is not so easy as it looked in the beginning, as is very 

 clearly shown in two articles in the Chemikir Zeitumj. 



The author of these articles points out that, in case raw 

 sugar is to be used as one of the raw materials, the cost of 

 the yeast-fodder would be much too high even in war times, 

 not to speak of normal conditions. It is much better to use 

 molasses or the waste waters from the cellulose factories, where 

 wood is cooked with sulphites f )r being turned into paper 

 stuff. These liquids contain sugar, which may be used by 

 the yeast cells, while the price is not so high as that of the 

 sugar itself. But even in this case the good results are 

 douV)tful. The cellulose waste liquid has a very bad smell, 

 and it is not at all sure that the dry yeast coming from it 

 will be eaten by cattle, while in case of molasseS it is not at 

 all sure, whether it is wise to sacrifice such a well-known and 

 fully appreciated fodder as molasses in order to get, with 

 great expense and not at all in a sure way, another cattle 

 food, of which we do not know anything. 



The great difliculties connected with the formation of 

 yeast from sugar a ad ammonium sulphate consist chiefly in 

 the fact that the liquid nmst be very much diluted, and kept 

 in constant movement at a given temperature with huge 

 cjuantities of air, while in order to obtain a good assimilation 

 of the sugar, the amount of yeast cells to start with must be 

 enormously large. Besides, it is not po.ssible to start the 

 operation with part of the yeast obtained, but the initial 

 yeast must be prepared beforehand, which requires again 

 much expense. The li(piid must be .so much diluted as to 

 contain no more than 1 per cent, of dry substance. In higher 

 concentrations the yeast will not only grow and use sugar to 

 that end, but ferment same into alcohol and carbonic acid, 

 and destroy it in this way. One hundred kilos, of 

 sugar recpire -50 parts of nutrient salts, and thereby 

 yield 1.50 parts of dry substance, which, in a con- 

 centration of 1 per cent, yields a quantity of 1-5,000 

 parts. This large cpiantity is to be kept at a given temperature 

 and supplied with enormous amounts of air, requiring mighty 

 air-pumps and enormous tanks. After the action is over the 

 yeast has to be separated from the liquid and the latter disposed 

 of, which is also a matter bristling with difficulties. We find 

 figures on the size of the yeast tanks, the capacity of the air- 

 pumps, etc., necessary to drive a comparatively small factory 

 for albuminoids from ammonia and sugar, which clearly show 

 that the process is not yet mature and certainly not able to 

 yield already now considerable amounts of yeast far 

 fodder. Yet it is rumoured that the German Government 

 contemplates the seizure of all the molasses in order to 

 have it transformed into yeast-fodder. The CentraUJatt 

 fur die deutsche Zuclcevinduurie brings an article in 

 which the calculation is made of the number of facto- 

 ries, with the tanks, calorisators, air-pumps, centrifugals, 

 drying houses, etc., which must be erected within a few 

 months' time to convert all of that molasses into nitrogenous 

 fodder. The author of that article points out that after 

 much trouble the farmers have been induced to use molasses 

 as cattle food, of which they have learned to appreciate the 

 value, and now suddenly that useful article would be with- 

 drawn from them in order to make place for a yeast food. 

 It is not in the interest of the industry and certainly not 

 favourable for the health of the cattle if suddenly so large 

 changes are made in the tnethods of feeding. 



