GARDENERS' CHRONICLE 



OF AMERICA 



DEVOTED TO THE SCIENCE OF FLORICULTURE AND HORTICULTURE 



ADOPTED AS THE OFFICIAL ORGAN OF 

 THE NATIONAL ASSOCIATION OF GARDENERS 



Vol. XVIII. 



lULY. 1914. 



.No. 3. 



Electricity and Plant Culture 



By Arthur Smith. 



Of all the natural forces the mo.st fertile in its sub- 

 servienc}- to the necessities and luxuries of man is un- 

 doubtedly electricity. No degree of familiarity, however 

 long continues, can efface the sense of wonder at the ef- 

 fects of the many applications to which this mysterious 

 force can be put. Whether the mystery surrounding the 

 chemical character of electricity will ever be solved or 

 not is an open question. It is possible that in the future 

 the elements, if there are any, which enter into its com- 

 position, may be stated in chemical terms, but at the 

 same time it is rather doubtful. Whether electricity be 

 a simple or compound substance is, however, not of great 

 practical importance, at any rate so far as this article is 

 concerned. It will therefore be unnecessary to consider 

 the technology of electricity, merely stating that it is 

 universally present in nature in a more or less latent 

 state — in a state of quiescence and e(|uilil)rium — but this 

 state is one which is very easily disturbed and it appears 

 that however great the quantity of electricity a body may 

 contain it is ineffective unless transformed into a cur- 

 rent. It may be assumed that frictional, voltaic and ani- 

 mal electricity are one and the same thing, the distinction 

 merely being in the mode of generation. 



The \'cr\' general distribution of electricity throughout 

 almost every substance, and the state of activity it dis- 

 plays around growing vegetation, has led at various 

 times to the belief that were means devised to divert a 

 more than usual quantity of it through plants, their 

 growth could be much accelerated. 



.At present it is impossible to define to what extent the 

 growth and develojament of. living organisms depend 

 upon electricity, but we know at least that it is more or 

 less beneficial. The fact has been definitely established 

 that electric currents exist in the soil and in the plant; 

 in realitv wlierever chemical activit\- occurs electric cur- 

 rents are likely to be present, although these currents 

 may be comparatively insignificant and require very deli- 

 cate instruments for their detection. 



Probably many have noticed that rain accompanied 

 with a discharge of electricity through the atmos]>here 

 has a far greater beneficial effect upon growing plants, 

 grass for instance, than a similar amount of rain under 

 like circumstances, but without the electricity. The rea- 

 son of this is that the form of electrical discharge known 

 as lightening produces nitric acid and ammonia by caus- 

 ing their elements to combine in the atmosphere ; the 

 rain which generally accompanies it brings these valuable 

 plant-foods down to the soil. This power of electricity 

 is now being made use of in the manufacture of nitrates 

 for commercial purposes to take the place of nitrate of 



soda. From this it is easily understood that a current 

 of electricitv passing through the soil will have a similar 

 effect in causing the combination of the elements con- 

 tained in the above plant-foods and thus rendering them 

 available. 



The idea of using electricity in an artificial way for 

 this purpose has frequently occurred, as it has long been 

 known that plants respond to electrical stimulus, and 

 many investigations have been made with a view of as- 

 certaining practical means of realizing the benefits of 

 this force. 



The first record which we have of any experiments in 

 electro-culture is of one made by Dr. Mainbray, of Edin- 

 burgh, m 1747, who passed the electric current through 

 plants in pots. In 1840 a lady, whose name has not 

 been handed down, conducted some experiments which 

 mainly consisted in causing a constant flow of frictional 

 electricitv through a portion of the ground in her garden, 

 with the eft'ect that vegetation did not cease during the 

 winter upon the plot under the influence of electricity, 

 and that what snow fell upon it during the continuance 

 of the e-xperiment never remained as it did upon the rest 

 of the garden around. This result caused Dr. Forster, 

 of Elginshire, Scotland, to place a small galvanic battery 

 in action upon a grass plot, and the effect produced fully 

 confirmed the results of the lady's experiment. This and 

 the results of further experiments by Dr. Forster led 

 him to try the effect of collecting the free electricity of 

 the atmosphere by means of wires suspended upon poles 

 thirteen feet from the ground, and conveying it through 

 it through the soil by means of buried wires. The result 

 upon a plot of twenty-five square rods, part of a field of 

 barley, was that the electrified plot produced more than 

 double per acre than the rest of the field. .-\ full account 

 of this experiment appeared in the Times (London) of 

 October 2, 1844. One of the reviews in a leading article 

 at the time used the expression, "He turns the materials 

 of the thunderbolt to manure." 



.\lthongh these experiments were successful, as far as 

 thev went, as proving the beneficial action of electricity 

 upon plant growth, yet the question ren^ined in abey- 

 ance for nearly fifty years. .About the year 1890 Mon- 

 sieur Baral. of Garonne, France, applied electricity to 

 the culture of potatoes, tomatoes and hemp. A row of 

 hemp, subject to the influence of the electric current, 

 grew eighteen inches taller than the rows not electrified. 

 A kilogramme (2.2 pound) of potatoes planted in the 

 path of the current produced 21 kilogrammes of very 

 large, healthy tubers, while the unelectrified patch only 

 ^ave 12J/2 kilogrammes from the same weight of seed. 



