178 THE MONTHLY BULLETIN. 



The amount of fruit that should be left ou a tree is, of course, an 

 exceedingly hard thing- to judge. Some have advocated thinning with 

 the idea of leaving a certain number of boxes of well developed fruit. 

 While this might not be done with a very great degree of accuracy at 

 first, those who have tried it claim that in a very short time one will 

 learn just about how to space apples or other fruit, so that an amount 

 approximating a certain number of boxes is left. This spacing will, of 

 course, vary with kind of fruit and variety. In the experiments pre- 

 viously mentioned with apples, the spacing varied from 4 to 10 inches, 

 the latter distance proving to be none too much in the case of Winesaps, 

 which have a tendency to run small. If trees are well set with fruit 

 so that an even distribution can be brought about all clusters should be 

 broken up until no two apples touch, and all fruit on the tips of small 

 twigs should be removed. Careful, systematic work is necessary for 

 the greatest success. He who goes into his orchard with a pole and 

 knocks otf some fruit here and there has not thinned. True, he has 

 relieved the tree of some of its burden, but, in all probability, in such 

 a way that he will not be repaid to any extent for his efforts. 



The few ideas set forth in this paper have not been given without a 

 knowledge of the fact that many are practicing thinning with success. 

 It is not a new thing in California and there are, no doubt, those in the 

 hall to-day who have had experience and can throw manj^ side lights 

 on the points that I have tried to bring out. There is no question in 

 my mind, however, but that the whole subject is one which has been 

 dealt with in a superficial way, not only by fruit growers, but experi- 

 ment station workers as well, and that there is great need for carefully 

 conducted thinning experiments with the different fruits, so that data 

 possessing something of scientific accuracy may be obtained. The 

 many and varied problems that suggest themselves to the horticultural 

 investigator in their solution afford abundant opportunities for service 

 that will be of great value to the future fruit interests.. While the 

 orcliardist must depend principally upon the trained worker from the 

 experiment station or elsewhere for the solution of most of these prob- 

 lems, I would like to make a plea for more experimental w^ork in a small 

 way, at least, by the orchardists themselves,' and why not plan some 

 careful thinning experiments? A half dozen trees carefully thinned 

 early in the season, an exact record being kept of the co.st of the opera- 

 tion, can be compared at picking time with a half dozen others along- 

 side, where no thinning was done. If time permitted several such 

 experiments differing in the amount of fruit taken off, could be carried 

 through. The value of such work might be very great and there is no 

 man who owns an orchard who couldn't take time for such little experi- 

 ments as these. 



IDAHO'S QUARANTINE AGAINST PEAR THRIPS. 



By A. J. Cook, State Commis.sioner of Horticulture, Sacramento. Cal. 



In her c[uarantine against the pear tlirips, Euthrips pyri, the State 

 of Idaho included Placer County. A few years ago an agent of the 

 Department of Agriculture reported that this pest Avas in the Placer 

 County orchards. Later i\Ir. Dudley Moulton corrected this statement. 



