The Gardener's Monthly 9: 144-145 (May 1867)
Influence of the Graft on the Stock
This is a question like unto which few seldom occurs, that is to say one of importance alike to the practical man and to the man of science. It has been universally believed that there is no such influence, and to this day only a few of the most progressive minds see an affirmative tendency in the question. Day by day, however, the evidence accumulates; and we entertain no doubt, now that attention is well directed to the subject, numerous observers will record facts proving beyond doubt that the influence on the stock is of the most positive character.
Several nurserymen have assured us that in digging up rows of apple trees, each variety will have its own style of roots, although the stocks be of the most diverse character, and we remember a correspondent in our paper some years back giving a detailed account of some observations of this kind; though, unfortunately, under some other heading it cannot be traced through our index. Mr. Adams also gives similar facts in our present number.
But after all there are few more curious illustrations of this view of things than Mr. Stough's Pear sprout from a mountain ash stock, an illustration of which we give herewith, showing the pear sprout seven inches below the graft on the mountain ash stock.
As some well versed in natural philosophy have considered it impossible that this pear should come out so far below the graft, Mr. S. has got a neighboring nurseryman to give us an account of it, whose report is clear as to the fact.
It is very dangerous, in the present state of our knowledge of the developments for any one to speak positively about the "laws of form," or how they operate. We see every day what are called "freaks of form,"— freaks which we look to "accidental external causes" for the origin. But, it is evident these external causes, can only develop pre-existing germs; and these germs always develop in one uniform way. The gall fly, does not make the gall, it is only the instrument of its development. Hence the peculiar form of the gall is the special prerogative of the plant, not the work of the insect, as if it were a bird making a nest. These seeds of form appear to reside in the cells, and perhaps may permeate the whole plants system, finding its easiest but not sole source of development through the seeds reproducing the individual plant.
Some years ago there was in the garden of the late C. J. Wister, of this place a tree of the curled leaf willow, (Salix bab. annularis) perhaps 20 years old. Then a branch strong and vigorous of the common weeping willow pushed out from near the top of the tree. Now it is evident the plant could only do this by a form seed or cell remaining in the curled leaf sprout at the original change and which must have floated in a dormant state through the circulation for so many years.
How this is all accomplished we know nothing at all; but we see enough to show us, that there are many hidden mysteries, which we may perhaps someday be permitted to unravel; but which for the present should make us very cautions about pronouncing phenomena we hear of utterly impossible, when we know so very little about the possibilities of form development in plants.