New YorK AGRICULTURAL EXPERIMENT STATION. 247 
bundles. This latter consideration is of importance in practice, 
since it accounts for shaded leaves being more tender for eating. 
That shade grown-plants contain a smaller percentage of non- 
nitrogenous matter (also of total dry matter) than do normally 
erown plants is shown by analyses by Géneau de Lamarliére* 
Sachs? and Berthelot® among others. 
Again, there is little storage of reserve material in shaded 
plants since the most of that manufactured is used up at once 
in the metabolism of the plant. As a consequence, storage organs 
such as tubers and roots remain undersized, or in the case of 
fruits their number is diminished though the size of the indi- 
vidual may be increased as in the case of shade-grown oranges. 
Fruitfulness is diminished by shading, in part at: least, as a 
result of restricting the manufacture of reserve material. That 
fruitfulness is not governed by access of light to the fruiting 
organs themselves is demonstrated in the common practice of 
covering buds to avoid cross-pollination and keeping the fruit 
covered to its maturity. 
The effect of shading in conserving soil-moisture by diminish- 
ing evaporation has already been discussed (p. 254). The gen- 
eral effect on transpiration is also greatly to reduce it, thus fur- 
ther conserving soil moisture. The factor chiefly concerned in 
producing the change is velocity of wind. Wiesner* has shown 
that in the case of some species of plants the rate of transpiration 
may be increased by a strong wind to twenty times its rate in still 
air. In occasional species, however, wind has the effect of check- 
ing transpiration. The extreme effect of a given velocity of 
wind is obtained when the current of air strikes the transpir- 
ing organ at right angles. In shading, losses from excessive 
transpiration caused by air currents are reduced to a very low 
rate. Their maximum effects are done away with entirely, since 
the plants are protected above all from descending currents. 
The effect of reducing the intensity of light is also on the 
whole to reduce transpiration. In experiments by Fittbogen® 
1Compt. Rend., 115: 368 (1892). Abst. in Bied. Centbl., 23: 351 (1894). 
2Cited by Vines, S. H. Physiology of Plants, p. 253. 
3Compt., Rend., 128: 139 (1899). Abst. in Hap. Sta. Rec., 11: 420 (1899). 
‘Der Naturforscher, 21: 225. Abst. in Bied. Centbl., 18: 135 (1889.) 
5Cited by Sorauer, Pflanzonkrankheiten; 2 ed., p. 480. 
