MISSOURI BOTANICAL GARDEN BULLETIN 109 
Severe cutting back is sometimes necessitated when regular 
pruning has been neglected, the degree of severity depend- 
ing upon the power of the tree to send out adventitious 
buds. Sycamores, soft maples, elms, and poplars lend them- 
selves well to heading back. 
The operation of pruning should begin at the top, as 
by doing so it is easier to shape the tree, besides saving 
time in clearing off the cut limbs. All cuts should be made 
close to the base of the limb and parallel to the axis of the 
trunk. Stubs should never be left, as decay would soon 
ensue, penetrating to the heart and eventually destroying 
the tree. To avoid splitting and tearing the bark, the limb 
should be sawed half way through on the under side about 
10 inches from the base, and the final cut made at the 
shoulder. The weight of the limb will cause it to split off 
at the upper cut without injuring the bark. If the limb 
is so large as not to split horizontally to the upper cut, the 
cut at the shoulder is made half way through and then an- 
other cut opposite will cause the limb to drop off. The stub 
left is then easily sawed off without damage. No matter 
how small the scar, a protective and disinfectant dressing 
should be applied immediately to prevent decay until the 
callus grows over the wound. Paint made of linseed oil 
and white lead makes a good dressing provided it is applied 
again after checking of the wood has taken place. Coal 
tar and various asphalt preparations also make desirable 
dressings. 
Heavy pruning should be done in the fall or winter while 
the trees are in a dormant condition. The shaping should 
be done during August or September when it is easier to 
discover the weak, imperfect or dead branches. Early spring 
or summer pruning is not advisable, as the rapid flow of sap 
leads to bleeding, stripping of the bark, and a check to the 
root system by removal of elaborated food material. 
The tools required for pruning are: pruning saws 
of various sizes, but always single-edged, as a double- 
edged saw is harmful to the tree; an ax; a pole pruner; 
pruning shears; and a ladder. 
Ornamental Shrubs, Roses, and Vines.—The pruning of 
shrubs at the time of transplanting is similar in principle 
to that suggested for trees. A balance should be maintained 
between the root system and the to by cutting back the 
individual branches at least one-fourth, the severity depend- 
ing upon the root system and the species planted. The gen- 
eral purpose of pruning shrubs is to aid the plant to assume 
its natural form and characteristic beauty, and therefore only 
