36 MASS. EXPERIMENT STATION BULLETIN 209. 



erally lime-sulfur has been used for scale control, but in 1912 and 1913 

 miscible oil was applied in the late fall. This was followed by the dying 

 of branches on some trees, which was attributed in part to the use of the 

 oil, so that it was discontinued. One or two summer sprays have been 

 given except in a very few years when the crop promised to be very light. 

 Curculio injury has been common in most years, and in 1913 the red bug 

 was found to be present. Partial control of these pests has been secured 

 by the use of nicotine preparations in the spray. During the early years 

 copper sulfate preparations and Paris green, and recently lime-sulfur and 

 arsenate of lead, have been used in the summer sprays. 



No records of growth were taken previous to 1902. Beginning in that 

 year the circumference of the trunk 6 inches from the ground has been 

 measured annually except in the years 1905, 1906, 1910, 1912 and 1918. 

 Records of the yields of drops and picked fruit for each variety from each 

 plot have been taken each j^ear. The yield of individual trees has not 

 been taken. 



Five trees have died since the orchard came into bearing. One Graven- 

 stein in plot 1 died before 1907, and another in 1919. The remaining 

 Gravenstein in this plot was girdled by mice in 1907-08, but was bridge 

 grafted and is now in good condition. One Baldwin in plot 3 died about 

 1913, one Roxbury Russet in plot 4 died in 1907-08, and one in plot 2 in 

 1919. (See page 34.) These have all been replaced, but none of the 

 3'oung trees is in bearing. In the tables given for trunk circumference the 

 missing trees are omitted from the averages, but no corrections are made 

 in yields. 



Growth Records. 



The only record of tree growth is that of trunk circumference which 

 has been taken in most years beginning in 1902. Fig. 1 shows the averages 

 of these measurements by plots. It may fairly be assumed that at the 

 start the trees on the several plots averaged the same size. The differences 

 in 1902 show what happened under the system of sod with removal of the 

 hay. The manure and sulfate plots were alike, averaging about 27 inches. 

 The graph shows that these two plots have steadily diverged up to the 

 present time. 



Certain years, such as 1904 and 1908, seem to have been especially 

 favorable to tree growth, while 1917 was unfavorable. The writer has 

 tried to correlate these variations in growth with rainfall, temperature, 

 sunshine and size of crop, but without very much success. It is evident 

 that no one of these factors is entirely responsible. 



The relative growth on the different plots is more clearly shown in 

 Fig, 2, where the average trunk circumference of the trees on plot 1 is 

 shown as 100, and that of the other plots as percentages of plot 1. The 

 steady decline of plot 5 from 100 to 89 per cent is clearly shown. Plot 2 

 (wood ashes) had fallen to about 88 per cent in 1902, and continued to 

 fall off slowly until about 1912, but since that time it has nearly held its 

 own. Plot 4 (bone and muriate) has behaved about the same as plot 2. 



