No. 7. DEPARTMENT OF AGRICULTURE. 397 



bring that climate here, but you can select those subsoils which have 

 such water holding capacity that their temperature will make up 

 in part for those climatic conditions, and thus be of material assist- 

 ance in growing a finer textured York apple. 



Dr. Voorhees in an address to the New Jersey Horticultural So- 

 ciety last year (see page 153 of New Jersey Horticultural Society, 

 1909) said he thought color to be largely dependent on climate and 

 sunshine, but to some extent the presence of iron might assist. 

 In hearty accord with this it seems to me that attention has not 

 been called to one of the most important factors, unless Dr. Voor- 

 hees meant to include it under the general heading "climate," and 

 that hardly seems probable. There are certainly two conditions 

 of climate in which every tree finds itself trying to grow, viz., the 

 one above the sruface of the ground and the other below. The former 

 is much easier to observe than the latter, and to it much thought 

 and study have been given. But soils vary greatly in their capacity 

 t(» hold water, and this variation depends largely upon the texture 

 of the soil, /. c, upon the size of the soil particles. 



But the structure of the soil also plays an important part in 

 determining in many cases the moisture conditions, though that is 

 not necessarily its most noticeable effect on tree growth. Soil tem- 

 peratures depend largely on the water-holding capacity of the soil. 

 The soil particles warm uj) in the spring much more readily than 

 the water contained in the soil. So does the humus, but the rela- 

 tively small percentage of it in any good fruit soil makes it a factor 

 of lessor importance as far as its temperature is concerned. Conse- 

 quently a soil that holds the most water is the last in the spring to 

 become warm enough for the planting of crops. Hence we com- 

 monly call a sand a light soil because it is ready ot Avork early in 

 the season, whereas clay is considered a heavy soil because it retains 

 moisture well and cannot be worked until later. As a matter of 

 fact, the opposite is true so far as the weights are concerned, a 

 given volume of sand weighing more than an equal volume of clay. 



If, then, subsoils well-drained from free water be selected within 

 the York region that carry a maximum of capillary water their 

 temperatures will be sensibly lower, especially during the mid- 

 summer months, than those of lighter textured subsoils that carry 

 less capillary water. In this way slight check to rapidity of growth 

 may be effected and thus give to the fruit a somewhat finer texture. 



To obtain, then, the best quality of York Imperial consistent 

 with heavy yield and good exterior appearance this variety should 

 be planted, I believe, on a heavy well-drained soil. A mellow clay 

 loam surface underlaid by clay loam or even clay in this region, 

 so long as it is not stiff enough to prevent the ready penetration 

 of the roots, would be particularly desirable. The elevation of 

 South Mountain above the surrounding country is undoubtedly a 

 desirable factor, though its superiority over the lower slopes of 

 the same range could hardly be very marked where the soil condi- 

 tion are equalized. 



There are no soils in this vicinity too heavy for the York Im- 

 perial. Hence T would suggest that the heaviest or most clayey 

 soils be selected for this variety, where drainage is good and at 

 the highest. local elevation available. The Cecil soils as mapped in 



