302 



THE POMOLOGIST AND GARDENER. 



1871 



Interesting Experiments About Sap.— Blood 

 for the Grape Vine. 



By Jacob Staufper, Lancaster, Pa. 



Ed. PoMOLOGiST AND Gakdbner.— In the Gar- 

 dener's Monthly, March, 1868, p. 75, Dr. J. 'Stayman, 

 in a very interesting article, indulges in the follow- 

 ing remarfe. : "No journal can become popular that 

 is purely pi-actical, unless man should cease to think 

 and become a monkey." 



The more we study nature, the more we find 

 hidden and imposing forces e.xist, where the super- 

 ficial observer only sees inertia. It is known 

 that plants like animals, have a circulation. The 

 sap, as proved by Hales, in his experiment, by fit- 

 ting a long tube to the stem of a young vine which 

 he had severed, saw this fluid rise forty-four feet 

 high. This led others to experiment. In fact, De 

 Candolle, who was one of the last to move in this 

 matter, noticed that the force with which the sap 

 rises in the vessels of the plant is equal to the pres- 

 sure of two atmospheres and a half, equal to the 

 weight of a column of water eighty feet in height. 

 Various authorities can be given that the sap rises 

 in the vessels of the vine with at least five times as 

 much force as the blood circulates in the crural 

 artery of the horse — the most important blood ves- 

 sel of the thigh.— Even the matter of fact Huxley, 

 in his Lay Sermons, page 125, gives expression in 

 these words : "The wonderful noon-day silence of a 

 tropical forest is, after all, due only to the dullness 

 of our hearing ; and could our ears catch the mur- 

 mur of these tiny maelstroms, as they whirl in the 

 innumerable myriads of living cells which consti- 

 tute each tree, we should be stunned, as with the 

 roar of a great city." Men deemed materialists, 

 like Huxley and Darvin, admit forces which exist 

 and operate in a manner and way past finding otit, 

 so every man (unless he is a fool) will. 



We may say however, that the sap or fluid 

 absorbed from the earth by the roots of plants in 

 its crude state, is water, holding earthy and gaseous 

 matters in solution, especially carbonic acid; but as 

 it rises through the tissue of the stem it dissolves 

 the secretions which it meets with in its course, 

 and thus acquires new properties, peculiar to such 

 secretions lodged in the plant, differing entirely by 

 the time it reaches the leaves and flowering buds. 

 In trees the sap is mostly confined to the outer part 

 of the wood, hence called sap-wood. It is not cer- 

 tainly known through what kind of tissue the 

 upward motion of the sap takes place, but it is 

 probable that it is carried onwards through all the 

 tubes and vessels of the wood and their inter-cellu- 

 lar passages. The dotted vessels of the wood 

 seem more especially destined to fulfill this oflSce 

 when the sap is in rapid motion ; but as they 

 afterwards become empty, while the ascent of the 



sap continues, there can be no doubt that the 

 woody tubes or pleurenchyma, (juicy ribs) offer 

 the most constant means by which the sap is con- 

 veyed. 



It is by the root and leaf the plant is nourished. 

 The leaves imbibe moisture by the whole of their 

 surface, by every pore, whilst it is only through the 

 smaller fibres and spungioles of the root that water 

 is taken up from the soil. An instinctive power 

 seems to guide the roots to seek nourishment. Dr. 

 Davy brought forward a case in which a horse- 

 chestnut grew on a flat stone, the roots passing for 

 seven feet up a wall, then turning over the top of 

 the wall and down again seven feet to the earth. 

 According to Malherbe, "A New England Acacia, 

 which had become weakly and languishing after 

 having exhausted the sterile soil in which it was 

 planted, at last driven to quench its thirst, threw 

 out one of its roots across a hollow of sixty-six 

 feet, in order to plunge it into a neighboring well, 

 and spread out its fibers in the midst of the 

 water. From this time, he says, the tree reared 

 its sinking boughs and blighted leafage, after which 

 it grew with marvelous rapidity." 



De Candolle admits, without any circumlocution, 

 that absorption is an essential phenomenon, as does 

 Scnnebier, Saussurc and Desportaines. It is true 

 there are accessory physical forces, such as endosmo- 

 sis, capillary attraction, and hygroscopic action, that 

 is acted upon by the condition of the atmosphere 

 with respect to moisture. But it is a great error to 

 suppose these to be the special agents. The radi- 

 cles seem to select instinctively from the soil the 

 food of the plant, which is scattered through it. 

 But absorption is so little left to the chemico-phys- 

 ieal powers, that certain plants vegetate in soil 

 stufied with deadly substances without suffering in 

 the least from it. There are, however, cases iu 

 which it was shown that certain salts of copper, 

 mercury and iron, which kill plants, are yet absorb- 

 ed by them. But so with animals and it in no way 

 disproves the vital nature of the absorption of tht 

 roots. The spongioles of plants are sometimes 

 deceived, and introduce with the sap some poison 

 which kills them. Dr. Daubeny, Prolessor at 

 Oxford, states that the sulphuret of arsenic con- 

 tained in small quantities in the soil produces no 

 injurious cftects upon mustard, beans and barley. 

 He concludes that, to a certain extent, plants pos- 

 sess the power of selecting from the constituents 

 of the soil in which they live- Much more might 

 be stated to prove that absorption by the roots is a 

 vital act. 



I may thus far have failed to be "purely practical." 

 When I review the host of articles on the grape 

 vine, scattered over the pages of the Monthly 

 Gardener, Horticultural journals, &c., »&c., for years 

 past, with the conflicting views and experience of 



