92 



PEACH LEAF CURL: ITS NATURE AND TREATMENT. 



On the unsprayed trees, prior to the middle of May, the total amount 

 of new growth on 16,188 inches of 1891: wood, including the older wood 

 from which this arose, was 10,599 inches. On the sprayed trees the 

 new growth amounted to 17,045 inches during the same time (two 

 months) on 8,260 inches of 1894 growth, including the older growth 

 from which the latter arose. This was a net gain of 215 per cent, 

 length of old wood considered, over the growth produced by the 

 unsprayed trees. Otherwise stated, the unsprayed trees had averaged 

 a new spring growth of 7.85 inches per running foot of 1894 wood and 

 older, while the sprayed trees had produced a growth of 24.75 inches 

 per foot of 1894 Avood and older during the same time. This shows 

 a gain in growth on the sprayed trees during these two months of 

 16.90 inches per foot of old wood. The importance of this matter 

 will appear to all growers who have peach orchards situated where the 

 spring growth represents the major part of that of the season, as is 

 true in many peach-growing regions. In such orchards this would 

 frequently represent a reduction of 25 per cent in the annual growth. 

 In the peach, the growing wood of one year is the bearing wood of 

 the next, hence the amount of wood produced would have added sig- 

 nificance. 



Considering the total growth of the spring of 1895 from wood grown 

 prior to 1894 — the pushing of dormant or quiescent buds — an analysis 

 of the table shows a net gain by the old wood of sprayed trees of 173 

 per cent above the growth produced from like wood of unsprayed 

 trees. This action of spray enables the grower to renew bearing wood 

 on the lower portions of his trees, which is an advantage where trees 

 are old or close set and tending to grow upward, or where curl or other 

 causes have tended to denude the lower limbs of young and productive 

 wood. This tendency of Bordeaux mixture to aid in the forcing and 

 active growth of dormant Ixids was especially well marked in the case 

 of a tree sprayed very thoroughly on one side (6 pounds copper sul 

 phate, 4 pounds quicklime, 45 gallons of water) and left unsprayed on 

 the other. From the base of the main limbs on the sprayed side there 

 arose 13 shoots from dormant buds during the first two months of 

 spring growth, while the unsprayed limbs produced practically none. 

 The 13 shoots on the sprayed side had made the following growth to 

 May 17, growth beginning about the close of the first week in March: 



As shown by the table, the growth coming from 13 dormant buds 

 at the base of the main limbs of the sprayed side of the tree during 

 the first two months of spring growth amounts to 36 feet and 1 inch, 



