120 THE PLUM IN KANSAS. 



may be said that the less the knife is used on plum trees the better it 

 is for the trees. Most varieties require very little pruning after the 

 head is once formed. 



SOILS. 



Plums will adajDt themselves to almost any soil that would be chosen 

 for apples or pears. Domestica varieties are perhaps best on heavy 

 clay, and choice may be more restricted with them than with most 

 other sorts. The native varieties are suited to a wide range of soils, 

 but no tree will do well on wet, mucky soils, and, as the plum is a rank 

 feeder and a heavy bearer, the soil must be of good fertility. 



IRRIGATION. 



Frequency in the application of water is so entirely dependent 

 upon the character of the soil that no rule can be made to govern it. 

 How best to irrigate must be learned by experience for each orchard. 

 In a general way, it may be said that young trees require more water 

 the first season than is necessary in succeeding years. Trees that are 

 bearing, however, should receive almost if not quite as much as young 

 trees ; it is necessary for the best development of the fruit. The soil 

 of the Colorado station orchard is quite compact ; water does not 

 spread quickly, and each irrigation is prolonged for a greater time 

 than would be necessary on more porous soils. When water is avail- 

 able, we aim to apply it once in ten days for young trees ; somewhat 

 less frequently for those older. 



The effects of drought during July and August are frequently seen 

 'in small, inferior fruit. Reasonable care in the aiDplication of water 

 during this period will well repay the trouble in the increased quan- 

 tity and better quality of fruit. It is, however, possible to apply an 

 excess that may work as great injury as the most severe drought. It 

 is only by studying the appearance of the trees and the condition of 

 the soil that we can arrive at a correct adjustment of the quantity to 

 be applied and the time to apply it. It is the practice at the Colorado 

 station to withhold water after the 1st of September, in order to check 

 growth and allow the wood to ripen. If growing conditions are main- 

 tained through the fall, the young and succulent wood of even the 

 hardiest varieties is in danger of being killed by low winter tempera- 

 tures, but if well ripened it survives the extremes without injury. 



Twice within the last six years we have had open winters that 

 proved more productive of injury to trees than those of continuous 

 cold. There were long periods of warm weather, with no frost in the 

 ground, and no precipitation to supply the continuous evaporation. 

 The soil became very dry and the trees suffered in consequence. To 

 guard as much as possible against such injury, it is the practice to 

 give a late irrigation usually in November. If the ground can be 



