504 Bulletin 94 



stock. A greater percentage of grafts will set if the scions are pre- 

 pared as indicated in Fig. 8, B (the Biederman method) in which a 

 portion of the outer bark on the back is removed. In thus exposing a 

 larger surface of the green chlorophyll layer a better union is 

 secured. The grafts are bound firmly in place with strong cotton 

 twine and all exposed surfaces, including the top of stock and the 

 tips of scions, are covered with melted grafting wax to prevent 

 evaporation (See Fig. 9, B). Scions are made from mature, two to 

 three-year-old wood about one- fourth to three-eighths inch in diame- 

 ter. The wood should be cut late in winter and kept in a dormant 

 condition until used. This may be done by tying it into bundles which 

 are buried in cool, slightly moist sand on the north side of a building, 

 or placed in cold storage at a temperature of about 45 degrees F. 



Experience has shown that ordinary grafting wax will melt and 

 run in southern Arizona during hot days. In a series of tests to find 

 a wax that would resist the heat of summer without melting or be- 

 coming brittle, paraffin having a melting point of 65 degrees C. was 

 found most satisfactory. This grade of paraffin is not common, on 

 the market, and parowax is suggested as a substitute. It is necessary 

 to boil down the parowax until it will remain firm at a temperature 

 of 115 degrees F. 



PLANTING 



Good results have been obtained by this Station from plantings 

 made in the winter and spring. However, better growth was obtained 

 by planting from the middle of February to the latter part of March, 

 just preceding the growing season. The temperature of the soil and 

 air is moderate at this season and well suited to the growth of newly 

 planted olive trees. 



DIST.\NCE APART FOR PLANTING 



The fact that the olive is long-lived, makes the distance apart for 

 planting a question of great importance. For the best development 

 of the tree and the finest quality fruit, there must be space enough 

 between the rows so that the branches will not touch, thus pemiitting 

 sunlight to reach the tree from all sides. A distance of thirty-five to 

 forty feet apart is good spacing for commercial planting. Figure 10 

 illustrates an orchard with the trees well spaced. The distance may 



