5'4 



THF TROPICAL ACRTCULTURTST. 



[January i, 1885. 



physiology, systematic botany, chemistry, geology, mensur- 

 ation, is placet! in the best possible position to devote 

 himself successfully in after life to the practical pursuits 

 of agriculture, gardening, pomology, or forestry, according 

 to circumstances. No doubt, legal aud fiscal restrictions, 

 and foreign competition will in the future, as now, hamper 

 the cultivator aud prevent him from fully availing him- 

 self of the increased means which scientific training, coupled 

 with practical experience, will put into the hands of the 

 cultivator; but that is no reason why he should not get 

 all the advantage-; he can. From our personal experience 

 we can testify that young gardeners and foresters, in 

 Uermany more particularly, but also in Belgium, France, 

 aud Denmark, have much better opportunities of becom- 

 ing acquainted with the A. 1). 0. of their future life-work 

 than the corresponding class in England, and they avail 

 themselves of them too. In consequence, their competition 

 is likely to become increasingly severe, the more so as 

 they are willing to work for lower wages than are the 

 corresponding class here. Their wants are fewer, their ex- 

 penses less, and they are not puffed up by a little learn- 

 ing, but kno.v how to use their hands as well as their 

 heads. It must be remembered that we have to supply 

 labour, not only for our own forests and gardens, but to 

 skilled labour and supervision for our colonies and for 

 India. The proper tillage and the full development of the 

 resources of the vast areas constituting Greater Britain 

 devolve to a large extent upon supplies from the home 

 country. There can be no doubt which is the more' likely 

 to succeed — the raw lad, the know-nothing, or ne'er-do- 

 well, or the well-trained student of an agricultural or for- 

 estry college. Look, too, at the enemies we have to en- 

 counter—the insects which ravage, the fungi which destroy 

 our crops and our trees. We know hut too well the effects 

 of the Potato fungus, the Vine-growers among our neigh- 

 bours across the Channel have been all but ruined by hosts 

 of tiny insects, not unknown in our own vineries. Are we 

 to go on for ever blundering along in our contention with 

 these enemies, trusting more to chance and to the acci- 

 dent of season to tide us over difficulties, or are we to 

 be guided by thorough knowledge of the nature and tactics 

 of our enemies and the rational inferences to be drawn 

 from them ? No doubt it is true that great discoveries 

 must continue to be made by the specialist, and the man 

 who has the competence, the inclination and the time to 

 bestow on that pecuniarily most unremunerative occupation, 

 scientific research. But the power of turning these observ- 

 ations of the scientist to good account can only be exerted 

 by those sufficiently well drilled to be able to see the in- 

 significance of his researches, and this power can By no 

 other means so surely be obtained as by means of the 

 thorough training to lie had in a well-equipped School of 

 Forestry, Agriculture, or Horticulture. — Gardeners 1 Chronicle. 



THE FALLING LEAVES. 



As the time of year is upon us wheu trees and shrubs 

 begin to shed their leaves, a few remarks bearing upon 

 the subject may not be without their value to the pract- 

 ical gardener. In considering the question, it is necessary 

 to bear in mind that the natural aim of every plant is to 

 produce a perfect seed, and that when growing in a soil 

 and climate adapted to its special habits and peculiarities, 

 it produces no more of each organ that it requires for 

 the healthy perpetuation and reproduction of seed. When 

 the leaf has fulfilled its oflice, the nutritive fluids circul- 

 ating through it are withdrawn and it decays or dries up. 

 These fluids are absorbed in great part by the stem, through 

 the agency of the roots, and rising higher and higher are 

 at length deposited in the seed ; the functions of the 

 foliage being performed the leaves drop off, to be renewed 

 in the following spring. Some interesting experiments of 

 Zdller and Kissmiiller* have shown that while in early 

 summer the leaves of plants contain very considerable 

 amounts of nitrogen, phosphoric acid aud potash, these 

 substances are withdrawn into the wood of the tree with 

 the advancing season, so that before the leaves fade they 

 have lost the larger part of what was most valuable in 

 them, which the tree retaius for its future use. 



In some of these investigations on the leaves of the 



Beech tree it was shown that in their water-free substance 

 the highest " percentage amount " of nitrogen, phosphoric 

 acid, and potash is found when they open or expand in 

 the month of May, and this percentage quite regularly 

 decreases till they ripen and fall, hut the "absolute" 

 amount of nitrogen, phosphoric acid, and potash is greatest 

 in July, and from that time on decreases. At the Con- 

 necticut Agricultural Station last year samples of leaves 

 were carefully picked from an Oak tree and from a Chestnut 

 (Castanea vesca) on the following dates:— October 16 and 

 November 13, and submitted to analysis. On October 16 

 the leaves were bright green, and showed no signs of fading 

 or changing colour. On November 13 the leaves were brown, 

 having almost entirely lost their reddish tinge. Leaves 

 were falling from the trees, but not rapidly. 



Analysis of the Fresh Lean's. 



Total... won 100-0 1000 100-0 



The mineral matter (or ash) contained: — 



* Landwirthscliaft, J'eistuJts-Stativne", xvii, 30. 



Total... 2-330 3"8O0 1-813 2'97fi 



The leaves gat In -red on October L6 had ve: y nearly finished 

 their assimilating functions, while those gathered on Nov- 

 ember 13, we may assume, had nearly or quite ceased to 

 lose through resorption into the wood. 



The green Oak leaves lost between one-third and one- 

 half of the percentage of nitrogen in . their water-free 

 substance between the time that they began to change 

 colour aud the time when they became brown (dead). 

 The corresponding gain is found chiefly in the woody fibre, 

 and in the ether extract. 



From the data obtained by the analysis of the Oak and 

 Chestnut leaves gathered on November 13, it is seen that 

 the newly fallen leaves, with about M0 per cent of water, 

 contained in 100 lb.: — 



Oak. Chestnut, 

 tb. lb. 



Nitrogen ... ... ... ... 54 67 



Potash ... ... ... ... 17 38 



Phosphoric acid ... ... ... L'6 23 



Stable manure, with 70 per cent of water, contains about 

 5 lb. nitrogen, b' lb. potash, and M lb. phosphoric acid. It 

 must, however, be remembered, that while the nitrogen in 

 stable manure is readily available as plant-food, it is ex- 

 ceedingly likely that the nitrogen of fallen leaves is com- 

 parably inert. From these, facts we learn that Nature, in 

 causing trees periodically to shed their leaves, returns with 

 them to the soil a very large portion of the soluble in- 

 organic substances which had been drawn from it by their 

 roots during the season of growth. The amount of leaves 

 which fall yearly, according to Ebermayer.* varies con- 

 siderably, being larger in wet seasons than in dry — larger 

 on a rich soil than ou a poor one. It also varies with 

 the thickness of the forests. Other things being equal; 

 trees produce more foliage when standing apart than when 

 .standing in dense woods. 



The degree of rapidity with which, under ordinary cir- 

 cumstances, leaves undergo decay, has also considerable in- 

 fluence upon the extent to which the soil is capable of 



* J r erxuchs"$tatioiwn, xviii, 63. 



