498 
previously weakened by disease or me- 
chanical injury showed the most winter 
killing. This was especially true in Fre- 
mont, Pottawattamie, Mills, Iowa, Polk 
and Page counties, south of the Rock Isl- 
and railway, where no cases of injury 
found was traceable to winter killing 
alone. Here the blister canker or Illinois 
canker was the most common cause of in- 
jury and it is considered by the experi- 
ment station as a very serious menace to 
Iowa orchards. In a recent bulletin is- 
sued by the station on new _ fungus 
Pig. 2. Due_ to 
on Young Tree. 
Winter Injury. 
(Purdue Experiment Station.) 
Canker 
growths in Iowa, No. 131, there is a de- 
scription of this disease. In Harrison 
and Woodbury eounties, winter’s severe 
cold is the chief cause of trouble. 
Where orchards are afflicted with 
canker or other disease, the diseased 
wood should be cut out. That should be 
done at once. The cuts should extend 
back well into the healthy bark and wood. 
The wounds should be thoroughly cleansed 
and disinfected with any good disinfect- 
ant, as formalin, corrosive sublimate, 
copper sulphate, Bordeaux mixture, or 
lime sulphur, and then covered with 
paint. 
ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 
Where the trees have been weakened, 
provide them with a generous and con- 
tinuous supply of food and the soil moist- 
ure necessary to make the food available 
to the tree. This can be done by break- 
ing up the land and keeping the soil well 
tilled so as to form a dust mulch at least 
three inches deep. Whenever possible, 
apply manure, especially where the soil 
is too steep for cultivation. This will 
add fertility and helps to conserve moist- 
ure. This treatment will bring many 
trees back into good condition and, while 
they may not produce apples this season, 
its beneficial effects will continue for a 
good many years later. 
S. A. Bian 
Ames, Ia. 
Wounds 
No artificial medium can be applied to 
the surface of a wound which will induce 
it to heal more quickly. The activity of 
the healing process depends upon the 
character and position and the time of 
year when the wound is made rather 
than upon protective coverings. 
Large wounds which result from the 
removal of branches of considerable diam- 
eter, leaving a large surface of heartwood 
exposed, may with advantage be protect- 
ed by: painting the cut surface with a 
heavy coat of white lead, the sole object 
of this precaution being to protect the 
heartwood from decay until the new. 
growth, which forms from the growing 
tissue immediately under the bark, has 
had time to develop over the exposed 
dead wood and protect it from decay. 
A large number of waxes, paints and 
washes have been tried, and the con- 
clusion of the whole matter may be sum- 
marized in the statement that any sub- 
stance which is not corrosive or detri- 
mental to growth which will protect the 
heartwood from the attacks of rot spores 
will prove a satisfactory covering for a 
cut surface. Among such substances may 
be mentioned white lead, yellow ocher, 
coal tar, and grafting wax. 
L. C. CoRBETT, 
Washington, D. C. 
YELLOW LEAF. See Rosette. 
