124 REPORT OF STATE BOARD OF HORTICULTURE, 



the Petites or French prune, because there is not potash 

 enough to go around ; hence, we must supply this deficiency 

 by sowing broadcast throughout the prune orchards in the 

 spring, just before the first plowing, from two hundred to 

 four hundred pounds of muriate of potash per acre, and the 

 result will be satisfactory. 



In an article published recently in the Northwest Horticul- 

 turist, Prof. G. W. Shaw gives the reason for the using of 

 potash so concisely that I will give it here in full : 



ABOUT THE USE OF POTASH. 



"First — Potash is essential for the assimilation of carbon 

 and its elaboration into starch, giving strength to the cell 

 tissue. Thus the plant suffers greatly in its woody portions 

 in the absence of potash in requisite quantities. 



"Second — It is associated with starch in its trans-location 

 from cell to cell, and in its formation into sugar. Hence, the 

 size and quality of fruit is materially affected by a deficiency 

 of potash. 



' ' Third — It is required for a proper development of fruit 

 acids, so important in imparting an agreeable flavor to fruits. 



" Having thus set forth the above functions, which science 

 has demonstrated to be true concerning the relation of potash 

 to plant growth, it remains to state the evidence on which 

 rests my belief in the need of potash on the soils of the 

 Northwest, west of the Cascades. Soils are formed by the 

 natural disintegration and abrasion of the original rock 

 masses. This being the case, it follows that a study of the 

 chemical characteristics of the rocks of a specified region 

 will at least give some clue as to what may be expected to be 

 present in relatively large and small quantities in the result- 

 ing solid. To illustrate : In regions in which limestone rocks 

 are abundant, soils are materiall}^ calcareous. It may be 

 argued that the process of weathering, including the solvent 

 action of the water, changes the proportions in which these 

 soil ingredients are present. 



"This I admit in certain cases, but it cannot in any case 

 go so far as to supply material which is not present in the 

 parent rock, nor to make a soil even fairlj^ supplied with an 

 element which is present in only limited quantities in the 

 parent rock, and, in fact, in this particular case, the soluble 

 salts of potash as developed from the insoluble minerals, 

 largely feldspar, as shown by Merrill, will be to a considerable 



