Vol. XVII. No. 411 



THE AGRICULTUKAL NEWS. 



■arsenic when added to the soil in the form of sodium 

 arsenate, lead arsenate, or of arsenate trisulphide and 

 ^inc arsenite, stimulates the nitrogen-fixing powers of 

 the soil. This stimulation is greatest when lead arsen- 

 ate is applied and least when zinc arsenite is used. 

 Pans green (cupric aceto-arsenite) did not stimulate 

 m any of the concentrations, but became very toxic 

 when the concentration reached 120 parts per million. 

 The toxicity of this compound is due to the copper, 

 -and not to the arsenite contained in it. Sodium arsen- 

 ate became toxic when a concentration of 40 parts per 

 million was added, and 2.50 parts per million of arsenic 

 entirely stopped nitrogen fixation. On the other hand, 

 lead arsenate was not toxic even at a concentration of 

 400 parts per million of arsenic, while the toxicity of 

 arsenate trisulphide and of zinc arsenite was very small 

 -at this concentration. 



The above is of special interest in the West Indies, 

 on account of the use in cotton cultivation of Paris' 

 ^reen as an insecticide. 



Only one type of Azotobacter was isolated which 

 was stimulated by arsenic, and in this case the stimula- 

 tion was due to the organism utilizing its .source of car- 

 bon more econoinically in the presence of arsenic than in 

 its absence. Thus arsenic and its compounds do not 

 act as sources of energy to the organism. The main 

 part of the stimulation noted in the soil with its mixed 

 organisms is undoubtedly due to the inhibiting of 

 injurious species by the arsenic. 



Arsenic cannot replace phosphorus in the vital 

 process of the nitrogen- fixing organism, but it can in 

 some manner liberate the phosphorus from its insoluble 

 compounds. This may either be a direct or an indirect 

 action. 



i^» I ^ - 



Breeding Pure-Bred Stock. 



Pure-bred stock represents the accumulated effort 

 of generations of breeders leading to a well defined 

 end, which may be expressed in profits already realized, 

 or in profits to be realized in the future. 



In a review of some literature on the above sub- 

 ject, a writer in the Agricidtural Gazette of Canada, 

 October 1917, considers that to the intelligent breeder 

 the pedigree is the most important consideration to be 

 kept in mind. If there are animals, whose excellence 

 has been proved, most closely related to the genealogi- 

 cal tree, and if they occur in both branches of the 

 genealogy at the same time, the breeder may feel 

 a certain sense of security with regard to the power of 

 the strain to transmit superior characteristics. The 

 greater the number of descendants whose worth has 

 been proved, the greater is the certainty ■ as to 

 dominance of desired characteristics. With regard 

 to valuable animals, the length'of the pedigree is looked 

 upon by breeders as an indication of marked powers of 

 reproduction and selection. The length of the pedi- 

 gree is an Ojually valuable criterion in the descend- 

 ants, and it is here that a pure-bred animal is superior 

 to an ordinary one. The breeder of pure-breds, who 

 studies the indications connected with hereditary 

 power, and acts on these indications, is assured of pro- 

 fits which cannot he realized in ordinar\ animal pro- 

 duction for general market purposes. 



Poultry Feeding Places. 



> ia^3 ^<^"f'''^s^«"'^ AcjrkidUral Jowfnal, Septem- 

 ber 1917, refers to a bulletin of the West Australian 

 department of Agriculture, un the subject of the 

 necessity of cleanliness in the feeding places of poultry. 

 In many places the food is scattered on the ground 

 and the birds are continually fed wilin a small 

 space. Ihe surface of that space soon becomes fou) 

 with the droppings of the fiock. It is true that sun- 

 shine partial y acts as a germicide, but gener- 

 ally the spot becomes quickly contaminated with the 

 continual trampling of the fowls, and if there be 

 one sick fowl arnong them, the whole flock may soon 

 become infected. Spading up of the feeding place 

 once or twice a week will bring good results. It will 

 tend to purify the ground, and will induce exercise 

 on the part of the birds because of their having to 

 scratch tor their grain, and this is always desirable, 

 especially when poultry are confined in yards. If alsa 

 grain IS scattered as the ground is spaded up, much 

 will be buried so deep that fowls will not scratch iti 

 out, and some of it will be thrown up at the next, 

 spa.hng having already sprouted, and the crreeii 

 succulent blades are much r -Hshed by fowls. Of course 

 It must be remembered that the constant turning- 

 over of the same soil m a small poultry run mat- 

 eventually mean the reworking into the soil of heaps 

 of droppings, which is not good for the health of the 

 fowls. 



Growing of Corn. 



-An article on the above subject by Mr H W 

 Lynch, Agricultural Instructor, Jamaica, appears in the 

 Journal of the Ja^nwica AgrkMuml Society, 

 November 1917, which would seem to apply, afte- 

 making allowance for somewhat different conditione 

 to many of the smaller islands. The writer says in 

 answer to the question as to how much corn Jamaica, 

 is capable of producing, that if 50,000 acres were planted 



Y,. u ^'f'? ^^ ''"^ ^ ''^^''^ ''■""P- an-i if the yield were 

 20 bushels to the acre, the 1,000,000 bushels would 

 be just about four times as much as the usual importa- 

 tion of corn into .Jamaica. Touching the question as to 

 why so httle corn, comparatively speaking, is grown in 

 Jamaica, he «ays it depends upon whether it pays and 

 hat depends, on the other hand, on how it is cr^wn 

 If a man plants 1 acre of cassava or potatoes, and planti 

 peas and corn through it, and then gets only 10 busheb 

 which he sells at 3s. per bushel, it pavs him. for he get* 

 cassava and peas for his labour, and the corn is net, 

 profit. But if a man plants 1 acre of corn alone, after 

 the cost of cleaning, weeding and harvesting is mei 

 '^■Jr%T^ pay to sell at -3... per bushel, even if i^ 

 yields 20 bushels. To grow corn as a staple, and mak^- 

 It pay at ;>s. per bushel, it is necessary to plant it s.> 

 that the yield per acre shall be more than 20 bushels 

 Ihis can be done, for a yield of over 90 bushels to the. 

 acre has been obtained in some parts of .Jamaica If 

 by selection ol seeds, an.l proper tillage and manuring 

 the average yield is increased to 50 or ()0 bushels pe^ 

 acre, it will pay well to grow corn even as a pure crop. 



