40 BULLETIN 57, HAWAII EXPERIMENT STATION 
upper part of the flume, permitting the lighter particles of brown tissue 
to be carried off. In the refining process the starch is flushed out 
of the flumes into settling tanks 4 by 6 feet and 3 feet deep. By 
repeated levigation and removal of the brown sludge, a comparatively 
pure form of starch is secured. After the final settling the starch is 
agitated with water and pumped into a 30-inch sugar centrifuge. 
This machine reduces the moisture content of the starch to about 
40 per cent and lessens the time involved in drying the starch by 
heat. The starch is then broken into fine pieces and placed on trays. 
These in turn are placed for 24 hours in a tunnel drier 80 feet long, 
6 feet wide, and 7 feet high and resembling the ordinary counter- 
current fruit dehydrator. The dried starch finally is powdered and 
put into packages for marketing. 
The starch may be shipped from the factory either by way of 
the seaport of Kawaihae, 12 miles distant from Kamuela, which is 
located at the western edge of the agricultural area, or by railroad, 
which terminates at Paauilo, 18 miles to the eastward. 
SUMMARY 
The possibilities of the Waimea district as a canna-producing region 
has led to experiments with the crop on a field scale in that region. 
The Waimea district is a slightly rolling table-land (2,700 feet 
elevation) between Mauna Kea and the Kohala Mountains. The 
district is characterized by strong winds and frequent mists and fogs. 
The soil is of a porous nature and is derived largely from volcanic ash. 
Most of the soil of the Homestead tract is very fertile. 
The Waimea district is devoted to small diversified farming, but 
has need of a staple field crop which can be grown throughout the 
year and readily converted into cash. Edible canna gives promise of 
filling this need provided the crop can be utilized as a commercial 
source of starch. The crop is especially well adapted to. the region 
notwithstanding the comparatively low annual rainfall (43.5 inches). 
Methods of study of the edible canna are outlined which make 
possible the progressive study of the growth of the plant. 
Results of field experiments indicate the desirability of "seed" 
selection. Of the various types of rootstocks, the immature root- 
stocks with one or two buds gave the highest yields, followed by sub- 
surface and attached spike types. Mature rootstocks with no visible 
bud, detached spikes, and secondary immature rootstocks should be 
thrown out in selecting planting stock. 
Chemical treatment of seed did not prevent rotting. Rotting of 
the seed does not affect the growth of the hill unless development 
of the bud is delayed. Under Waimea conditions, seed should be 
planted at least 4 inches deep and at distances of 4 by 4 feet to permit 
cross cultivation. Planting two seed pieces per hill insures better 
germination and increases the yields somewhat but also increases the 
costs of seed selection and planting. Mulching with canna tops 
retarded germination and was not successful in preventing weed 
growth. Fertilizers failed to increase the yields of rootstocks appre- 
ciably. This is attributed to the high fertility of the soils on the 
experimental field. 
Results of monthly harvests (ninth to nineteenth month, inclusive) 
from one and two-seed plantings on 0.1 -acre plats showed an irregular 
but nearly continuous growth and unusually high yields of rootstocks. 
