20, 2 Lee and Shino: Citrus-canker Control Experiments 129 
Saigo is in Nagasaki Prefecture in the southern part of Kyushiu Island. 
The town of Saigo is on the sea while the orchard is about 3 kilometers 
inland and in the foothills of Mount Unsen; the orchard is at an elevation 
of about 60 meters above sea level. 
The Saigo region is not planted much to oranges. This orchard stands 
in the foothills, surrounded on the mountain side with scrub pine trees while 
toward the town are scrub pines with a few barley and soy-bean fields; 
there are no other orchards near at hand. This orchard is surrounded 
by several rows of some sort of coniferous tree making a fairly good wind- 
break on all sides. At the present time (December) the northeast mon- 
soon comes right off the sea and hits the orchard; the force of the wind, 
however, is somewhat broken by this windbreak. 
The orchard consists of about 6 hectares of navel orange trees said to 
be eighteen years old. The trees are planted on Citrus trifoliata stock 
and are consequently somewhat dwarfed, nevertheless they stand well 
above a man’s head, 2.5 to 4 meters high, and are very broad and compact. 
They are headed low, in much the same manner as California trees. 
The land has a decided slope but not so great that a wagon or sled 
cannot be pulled in all directions. In some places the orchard is terraced 
but it will be possible to select plats between such terraces. The orchard 
has been well cultivated (by hand) and is in fine growing condition. 
Fertilizers, soy-bean cake, and a fish-product fertilizer are applied abun- 
dantly in the spring, according to the owner. He has been bothered 
considerably by the fruits becoming badly blemished by canker and would 
welcome anything which would prevent the trouble. 
An idea of the size and character of the trees and the state 
of cultivation of the orchard may be obtained from a photo- 
graph of the orchard shown in Plate 1. 
The arrangement of the experimental plats is shown in fig. 1. 
The pruning indicated in plats 1, 2, 3, 4, and 5 in fig. 1 
was extremely careful, an effort being made to eliminate all 
cankers or at least to reduce them to but a few. As much as 
three hours were sometimes spent to a tree. In plats 13, 14, 
15, 16, and 17 more rapid pruning was attempted and this was 
called “rough pruning,” by the Japanese. In the case of these 
plats the sources of infection were greatly reduced, but no 
attempt was made to eliminate entirely the foliage cankers or 
to reduce them to but a numerical few. 
The cost of these methods of pruning was recorded and is 
shown in Table 4. 
The spray mixtures indicated in fig. 1 are so commonly used 
as to require little explanation. Lime sulphur at a concentra- 
tion of 82° Baumé was used in a 1 to 40 dilution with water, 
unless otherwise noted. Bordeaux 44-50 mixture was prepared 
in the usual way, adding diluted and recently slaked quicklime 
to a dilute copper sulphate solution; it was used immediately 
after preparation. Neutral Bordeaux mixture was prepared 
