96 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



the more restricted tracts of suitable river 

 bottom soils. 



E. R. Lake, 



Oi-egcn State Board Horticulture, 1911. 



See also article on "Adaptation of Va- 



METIKS TO E.WIRON'JIENTS." 



Volcanic Ash and Apple Culture 



The question is often asked, "Why is 

 the Pacific Northwest becoming so famous 

 for the production of apples?" There are 

 three general answers to that question. 

 The first is that the latitude is in the 

 great apple producing belt of the world. 

 Even where the latitude would seem not 

 to be far enough north the altitude of 

 the hills and mountain ranges often com- 

 pensates for the distance south, and gives 

 cool nights, and a temperature favorable 

 for the growing of the best fruits. 



Second, in a large part of this country 

 there is during the day a bright sunshine 

 and at night a cool air, both of which tend 

 to give color and flavor to the apple. 



Third, the character of the volcanic 

 ash soil, of which a large portion of this 

 region is built, is favorable for the growth 

 of the apple tree and its fruits. 



The following are the principal soil 

 elements necessary to the growth of the 

 apple tree: 



1. Nitrogen. 2. Salts of lime. 3. Salts 

 of potash. 4. Salts of phosphorus. 5. 

 Salts of iron. 



In the arid regions the soil is rich in 

 mineral substances, because the volcanic 

 ash, rich in these elements, has never 

 been leached by heavy rains. This soil 

 may be improved by the addition of barn- 

 yard manure or the growing of cover 

 crops like clover, alfalfa, or vetch, to 

 supply humus and nitrogen. In the hu- 

 mid regions where the rains of centuries 

 have leached the soil and where there is 

 a large vegetable growth it is sometimes 

 necessary to supply mineral fertilizers. 

 However, the general character of the 

 soil in the inland region is volcanic ash. 

 rich in lime, potash, phosphorus and iron. 



Further, there are numerous valleys, 

 with good drainage systems that are pro- 

 tected from heavy winds by hills or moun- 

 tain ranges, and in these valleys orchards 

 can be successfully grown without dam- 



age to the fruit from storms. In these 

 valleys irrigation is successfully carried 

 on and the melting snows in the moun- 

 tains furnish abundant water . 



In the bottoms the soil is sometimes a 

 deposit of sand, gravel, and wash from 

 the hill sides, favorable for the deep root- 

 ing of trees. On the uplands it is gener- 

 ally a fine ashy substance, into which 

 the roots may penetrate to considerable 

 depth. In places the wind has carried 

 it tor ages, and deposited it in coves, shel- 

 tered places, and behind the hills, so that 

 it may be under such conditions, 50 to 100 

 feet deep. However, in such deposits the 

 tendency is, under irrigation, for the soil 

 to puddle and become impervious to the 

 water, which prevents aeration, and the 

 percolation of water to a depth sufficient 

 for the root development of the large 

 trees. In such a case the best remedy 

 is the growing of alfalfa, with its strong 

 root system, which penetrates below the 

 puddled stratum, lets the water down, 

 aerates and nitrogenizes the soil and 

 opens up a new world of food for the 

 roots of the trees. In some places there 

 are strata of hard pan, which must be 

 broken up with dynamite; but in general 

 a volcanic ash region is a region most 

 favorable for the growing of apples. 



Granville Lowther 



WEATHER CONDITIONS 



The liability to frost is one of the 

 things that must be kept in mind in se- 

 lecting the most favorable site for an 

 orchard. Reference is made in the article 

 on frosts to the Thermal Belt where there 

 is not likely to be injurious frosts during 

 the seasons of blooming and fruiting. (See 

 Frost.) In this connection we would say 

 that there are three natural conditions 

 that protect from frost. The first is ele- 

 vation; the second, air currents; and the 

 third is the modification of temperature 

 by the warmer atmosphere from large 

 bodies of water. 



Elevation 



By elevation, we do not mean the dis- 

 tance above the level of the sea, but rel- 

 ative distance above the surrounding 

 country. For instance, if the general 

 level of a particular portion of the country 



