44 NATURE STUDY AND AGRICULTURE 
Some of the hardiest varieties of plums are the na- 
tive or wild plum, De Soto, Wyant, Sur- 
prise, and Forest Garden. 
Cherry- plums. — This term designates 
a hybrid or cross between a cherry and 
a plum. The sand cherry, which is 
native of the cold, dry Northwest, has 
been used for one of the parents and a 
good hardy plum for the other parent. 
The breeding is effected by preventing the 
pistils of the cherry blossom from being 
fertilized with pollen from the same 
species and instead thereof carefully 
dusting on them pollen from the plum. 
The resulting fruit is a hybrid, the 
breeder hoping to combine in it the de- 
sirable qualities of the two parents. The 
combination sought in this case was the hardiness of the 
wild cherry and the size and 
flavor of the chosen plum. 
Some hybrids of great value 
have been derived in this way, 
and they may now be pro- 
cured from most of our nurs- 
eries. The oldest and best 
known is the Compass Cherry ; 
but the Sapa, Opata, Sansota, 
and Cheresota are fast com- 
ing into prominence. Some of 
these should be plantéd in the Cees 
North by every fruitgrower. The favorite fall apple of Minnesota. 
Apples. — Apple growing has made considerable progress 
CHERRY-2 UMS 
The Compass Cherry. 
