PLANTING AND CARE OF THE ORCHARD. 33 



that are self-sterile and will not be productive unless near other 

 similar kinds. The following partial lists show varieties that 

 are both self-sterile and self-fertile but it is quite possible that 

 some of these may be self-sterile at one time and self-fertile at 

 another time or in another locality. 



An experiment with the Kieffer pear at the Michigan Agri- 

 cultural College during the summer of 1907 seems to indicate 

 that the Kieffer ought sometimes to go on the self-sterile list. 

 A Kieffer tree was enclosed in a canopy of muslin with one 

 branch left outside the canopy. The air within the canopy was 

 made to circulate daily by artificial means during the blossom- 

 ing period so as to insure pollination of at least some of the 

 flowers. Not a fruit set under the canopy, while the branch 

 that was left outside and was free to receive foreign pollen set 

 fruit freely. 



Preparing the land. 



(a) The land on which the fruit plantation is to stand 

 should be in as good condition as possible before the fruit plants 



