8 DEPARTMENT CIRCULAR 58, U. S. DEPT. OF AGRICULTURE. 
objection, however, is entirely eliminated when the trees are grown in 
bush form or with extremely low heads, which are the most desirable 
forms for this area. 
Pears can be budded on seedlings of the native thorn apple (Cratae- 
gus sp.), which is, of course, perfectly hardy. They can also be 
grafted on the June berry (Amelanchier). On June-berry stock — 
they produce dwarf trees. 
Mainly on account of a lack of sufficiently hardy varieties, very 
little experimental work in the propagation of cherries has been done. 
In the fall of 1918, however, a considerable number of buds of 
cherries were inserted on such stocks as Prunus besseyii, P. penn- 
sylvanica, and P. vir- 
gumiana, in order to 
test these stocks. 
Apricots and 
peaches can be 
budded — successfully 
on native plum and 
sand-cherry seedlings. 
Various methods 
of budding and graft- 
ing are being tested 
to determine which 
are best for this area. 
Excellent success has 
been met in winter 
grafting plums on 
both sand-cherry and 
plum roots. 
Under _ propaga- 
tion must also be 
considered the form and shape or type of tree as produced in the 
nursery. The ordinary high-headed tree, such as is shown in figure 
1, has not proved a success on the northern Great Plains and has been 
a decided failure in the rather extensive experimental plantings at 
the Mandan field station. Figure 2 shows a high-headed apple tree 
being killed by sun scald. To prevent this scald a special effort has 
been made to grow a number of bushy, trunkless trees and very low 
headed trees of the several tree fruits. The production of such trees 
in the nursery, both from grafts and buds, has proved a simple, prac- 
tical, and entirely successful undertaking by the practice of summer 
pinching. 
Two general types of trees have been produced: The central-axis 
tree with a stout main trunk supplied with well-developed branches 
Fic. 3.—A low-headed compact tree ready for planting. 
