COLOR 443 



light, the intensity of the light, the amount of foliage on the tree, 

 the healthiness of the foliage, the amount of stored food in the 

 plant, the soil heat, the texture of the soil, all have an influence 

 on the color of the fruit, it is clear that it is an intricate task, 

 and an almost impossible one, to determine in an experiment like 

 this what were the most potent factors. 



A comparison of the color data with meteorological data for 

 the twelve-year period shows that the treatment seemed to have 

 an influence in coloring fruit only in those years when the apple 

 did not develop well, as in 1893 and 1902 ; and that in other sea- 

 sons, as in 1896, 1900, and 1904, when climatic conditions were 

 favorable to the development of fruit and foliage, the coloring was 

 as nearly perfect on the untreated as on the treated plats. 



Experiment with basic-slag meal. From a very reliable source 

 we have an interesting account of an increase in the color of 

 apples by the application of basic-slag meal, an exclusively phos- 

 phatic fertilizer. About 20 pounds of the slag was spread around 

 the trees, most of it between 1 and 2 feet beyond the spread of 

 the branches. This was thoroughly worked into the soil. 



The fruit set was light, so far as yield is concerned, but the 

 increased size and the higher color of the fruit on the trees treated 

 in this way made the experiment a wise and profitable one. 



Experiments with nitrogen. From experiments carried on at 

 the Pennsylvania State College it has been found that nitrogen 

 has the effect of reducing the color of apples. 



Influence of cultivation on color. With apples, as with other 

 crops, probably the chief function of cultural methods is the proper 

 control of soil moisture. Other functions, such as promoting nitri- 

 fication and killing weeds, are important, sometimes more so than 

 moisture control, but the latter is usually the chief consideration. 

 This is especially true of fruit trees, the moisture demand of which 

 is large, both for use in transpiration and as a constituent of the 

 fruit and vegetative parts. Hence a shortage in water supply may 

 occur frequently in an orchard, at least for limited periods during 

 the season. This to a great extent reduces or nullifies the effect 

 of all other operations in the orchard. 



An experiment made along this line has shown that in an 

 orchard that was allowed to remain in sod, the color of the apples 



