PROPAGATION 57 



of the sun's rays. A water-proof wagon-cover, black on one 

 side and white on the other, is excellent for this purpose. 



"The bottom of the callusing bed is first covered with 2 or 

 3 inches of sand. The bundles of grafts are then placed in 

 a row along one end of the bed, and sand well filled in around 

 them. The bundles should be placed in a slightly inclined 

 position with the scions uppermost, and the sand should be 

 dry enough so that it sifts in between the grafts in the bundle. 

 The bundles of grafts are then covered up completely with 

 sand, leaving it at least 2 inches deep above the top of the scion. 

 Anotlier row is then placed in the same manner until the bed 

 is full. Finally a layer of 2 or 3 inches of moss or straw is 

 placed over all. 



"In the callusing bed we should endeavor to hasten and 

 perfect the union of stock and scion as much as possible while 

 delaying the starting of the buds and the emission of the roots. 

 The latter processes require more moisture than the formation 

 of healing tissue, therefore the sand should be kept compara- 

 tively dry. Between 5 and 10 per cent of water in the sand 

 is sufficient. The purer the sand the less water is necessary. 

 There should be a little more moisture present than in the sand 

 used for keeping the cuttings over winter. Too much moisture 

 will stimulate the emission of roots and starting of buds with- 

 out aiding the callus formation. 



"All the vital processes progress more rapidly when the 

 cuttings are kept warm. To delay them, therefore, we keep 

 the sand cool, and to hasten them we make it warm. In the 

 beginning of the season and up to the middle of March we keep 

 the sand cool. This is done by keeping the bed covered during 

 the day when the sun is shining, and uncovering occasionally 

 at night when there is no fear of rain. If the black-and-white 

 wagon-cover is used, the white side should be placed outward 

 to reflect the heat. The temperature should be kept about 

 60° F. or lower. 



