Boston Journal of Chemistry and Pharmacy, 9(3): 32 (Sept 1874)
ACTION OF CAMPHOR ON PLANT LIFE
|*Dr. Benjamin Smith Barton (1796) of Philadelphia wrote: "I put a piece of the woody stem of the Tulip-tree (Liriodendron Tulipifera) with one flower and two leaves..."|
In the latter part of the last century some experiments were made by a Mr. Barton, in England, upon the stimulating action of camphor on plants. A tulip*, placed in a solution of camphor, showed vigorous growth, and was longer in withering than other tulip slips, of the same kind, placed in ordinary water; and a withering yellow iris through treatment with camphor seemed, for some hours, endowed with new life. Barton came to the conclusion that camphor is a more powerful stimulant for plants than any other known substance; and he compared its action to that of spirituous liquors, or of opium, on the human body, when taken in certain quantity. These almost forgotten experiments have been recently repeated, in new forms, by M. Vogel of Munich, with very similar results.
M. Vogel obtained a homogeneous solution by rubbing camphor with water, and shaking camphor powder in a flask with distilled water. Two similar branches of a flowering syringa were then introduced, one into ordinary water, the other into the camphor-water. In twelve hours the former drooped and was near withering; the other branch stood upright, and without any sign of withering, — some of its buds were even developed, and it was not till three days after that it began to wither. Another flowering branch of syringa, which was nearly dead, was placed in the camphor-water, and a marked renewal and recovery was soon observed, which lasted some time. Frequent repetition of the experiment with branches of syringa showed the same result in varying degree.
The action of camphor on cut branches of living and fully developed plants naturally suggested the idea that the substance must also have an influence on the germination of seeds, and experiments proved this to be the case. Seeds of various plants were tested, and old ones were mostly selected, as their germinative force appears to be weaker than in fresh seeds. The seeds were spread out on some moistened blotting-paper covering a porcelain plate, aud a second moist paper was put over them.
For the first experiments, seeds of Lepidium sativum of the years 1869 and 1871 were taken. The entire duration of the germinative force of Lepidium sativum is known to be three years. The seeds of both the years mentioned, treated with ordinary water, showed a very imperfect, retarded germination, while the seeds moistened with camphor-water germinated very soon — those of the year 1869 in twenty-four hours, those of 1871 in seven hours. Similar results were obtained with other seeds, some of which were five or six years older than will ordinarily germinate. Treated with camphor-water, they not only germinated, but were several days earlier than fresh seeds under the most favorable conditions. In some cases not a single seed out of a large number sown in garden ground sprouted at all, while others of the same age started very promptly under the stimulus of the camphor.
The after development of some of the seeds that were treated with camphor was observed by Dr. Raob, the seeds having been put into the ground. It is interesting to know that the traces of the camphor treatment were here also visible, the young plants showing greater vigor and freshness.
These facts show that in camphor we have a stimulant for plants, capable of both strengthening the force and accelerating the rapidity of their vegetation. It is not probable that it will be of much practical value for that purpose, at least on a large scale, but the amateur will no doubt sometimes find it useful in starting his flower seeds, and we can imagine cases in which the professional floriculturist may employ it to advantage.