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BETTER FRUIT 



Page p 



roots. Caution — Never allow more than 

 a very little dirt above the union of the 

 bud or graft. This is of vital impor- 

 tance. The tree is very susceptible to 

 infection at this point of union. Great 

 care should be exercised in the selec- 

 tion of the trees to be planted. Only 

 such should be used as have been de- 

 veloped from proven trees of vigorous 

 growth and abundant fruitage of good 

 size. All trees should be rejected that 

 have imperfect grafted unions or that 

 show any other imperfections. Extra 

 money is well expended in securing 

 selected trees. 



Never top back a prune tree. I say 

 this knowing that there will be much 



criticism from many horticulturists. 

 Years of experience have proven to me 

 beyond question that it is a very bad 

 and injurious practice. Foliage and 

 root development go hand in hand, both 

 equally essential to tree development. 

 The tree should only be pruned dur- 

 ing the dormant season. AH branches 

 should be cut back to the parent limb. 

 All wounds from pruning or otherwise 

 should be surgically clean, and pro- 

 tected thereafter. 



Important: Special care and observa- 

 tion are required for the first few 

 months after planting, as this is one of 

 the most critical times of the tree's 

 life. The nursery tree has sustained a 



serious shock in transferring from the 

 nursery to the field. A stunted tree is 

 not worth time nor labor and should 

 be removed and replaced by a better 

 one. A winter legume cover crop should 

 always be secured as an aid to increase 

 soil bacteria and soil conditions. 



Maintain active leafage after harvest- 

 ing the fruit, that the fruit spurs may 

 be properly developed for the follow- 

 ing year's crop. 



If the fruit tree's physical economy 

 from center to circumference is never 

 allowed to become impaired by lack of 

 nutrition, or otherwise, I am confident 

 one hundred years of fruitage may be 

 expected. 



The Productive Mortality of Prunes 



By Earl Pearcy, Douglas County Fruit Inspector, Roseburg, Oregon 



HOW long will a prune orchard 

 continue to bear profitable crops 

 of fruit? \Mien will the decline 

 of old age begin to take place? These 

 questions are giving a greati 43a' of 

 concern to the prune growers Of the 

 state, who realize that sooner or later 

 their orchards must fall prey to senility. 

 The common impression is that the 

 prune is a short-lived tree whose span 

 of life would require three generations 

 to equal the Biblical allotment to man 

 of "three score and ten." Records 

 show that the walnut tree will live to 

 a very old age. What is there, then, 

 about the prune that limits its pro- 

 ductive period to a comparatively few 

 years? 



This matter of old age in our prune 

 orchards is deserving of study because 

 the prune industry of late years has 

 been a profitable branch of horticul- 

 ture, and if there is any practice or 

 operation within the power of the 

 orchardist which will lengthen the 

 bearing life of his trees or which will 

 delay for a few years the hand of Time, 

 it is well that we find what it is. There 

 is a suspicion among observant grow- 

 ers that the early demise of prune trees 

 may to a considerable extent be pre- 

 ventable. Such may be the case. 



A study made of the prune orchards 

 of Douglas County, in company with 

 Professor H. P. Barss, pathologist of 

 the Oregon Agricultural College, during 

 the summer of 1918 unexpectedly re- 

 vealed a condition that prompted this 

 inquiry into the matter of old age. 

 Heart rot, a term used for a group of 

 diseases which cause the decay of 

 wood, was found to be present in many, 

 if not all, of the orchards over twelve 

 years of age. In many instances the 

 rotten tissues had encroached upon the 

 sapwood of the tree until it was evi- 

 dent to the most casual observer that 

 the productive vitality was seriously 

 reduced. The wonder often was that 

 the tree could still be bearing at all. 

 It would seem at first thought that it 

 must take its entire energies to keep 

 barely alive. 



The situation proved so appalling, 

 corroborating as it did some earlier 

 observations of the California Experi- 

 ment Station, that the Agricultural Col- 

 lege immediately issued a pamphlet on 



"Heart Rots and Their Prevention," 

 which was sent out to the prune grow- 

 ers of the state in the hope that 

 orchard practices which were appar- 

 ently responsible for this damage would 

 be changed and precautions taken to 

 safeguard young trees from this dis- 

 ease. The barking of the trees, either 

 by cultivating implements or by the 

 poles of the shakers, can easily be pre- 

 vented. All pruning surfaces, espe- 

 ically those on large limbs or the trunk, 

 should be protected by Bordeaux paste 

 or disinfected in some permanent way 

 to prevent the spores of the rotten- 

 wood diseases, which are constantly 

 present in the orchard, from securing 

 a foothold from which to commence 

 their encroachment into the heart 



Forty-t\vu year old Petite prune tree. 



wood. Once within the tissues of the 

 tree there is no practical remedy. 



A second phase of this inquiry led to 

 a study of the damgae done by the 

 Prune Root Borer, which for several 

 years past has been under suspicion by 

 prune authorities, who have thought 

 that the injury done by this incon- 

 spicuous little pest was much greater 

 than commonly suspected. The life 

 history of this insect is such that aside 

 from the short time spent during the 

 summer in the moth, cocoon and egg 

 stage, the greater part of the year is 

 passed as a larva in the tree, where it 

 destroys the cambium layer or growing 

 tissue of the inner bark. Much of this 

 injury is hard to detect as the borer 

 confines its attention for the greater 

 part to the region of the tree from the 

 surface of the ground to a distance of 

 several inches beneath. 



Practically every prune district, or 

 one might say orchard, in the North- 

 west is affected by the borer, the in- 

 tensity of the attack varying from year 

 to year, for unknown causes, in the 

 different localities. As this worm does 

 not directly attack the fruit, and thus 

 make its damage visible as is the case 

 with the Codling Moth larva of the 

 apple, the average grower is unaware 

 of the total loss suffered annually. The 

 mortality among young trees is often 

 very high, necessitating a 10-per-cent 

 replant in many cases. As the circum- 

 ference of these small trees is not 

 great the chance of their being com- 

 pletely girdled is more to be expected 

 than for the old trees, although the loss 

 of old trees is frequent enough to cause 

 a large amount of dead space to occur 

 in the average orchard. Growers com- 

 plain that it is sometimes difflcult to 

 make the replants live when set out in 

 the old orchards, and after such an ex- 

 perience these men cease attempting to 

 fill in, thus losing available prune space 

 and increasing the overhead per acre. 



Undoubtedly the greatest loss comes 

 about indirectly, because while the 

 burrows of the pest may in most in- 

 stances fail to completely girdle the 

 tree, the actual destruction of such a 

 proportion of the sap transmission 

 tissue must tend to greatly weaken the 

 tree. How much of the sudden summer 

 drop of fruit, or of the small, inferior, 



