6 BULLETIN 72, HAWAII EXPERIMENT STATION 
crop as Napier grass necessarily means the removal of a considerable 
quantity of the available plant nutrients from the soil. Soils of good 
fertility, then, are of course desirable, unless liberal quantities of 
fertilizer can be used to supply the lacking constituents in the poorer 
soils. Most Hawaiian soils are suitable for the growing of Napier 
grass with the exception of some of the beach sands which have a 
high brackish water table, and some of the extremely heavy plastic 
clays which are poorly drained. Plats located at the Hawaii Experi- 
ment Station on a heavy clay bottom-land soil showed a marked 
yellowing of plants and a lower forage yield following a period in 
winch heavy rains had flooded the land and water had stood for but 
a few hours on the plats. Many of the upland residual silt loams and 
clay loams, fairly fertile and well drained, as well as the medium to 
deep ash soil types are quite suitable to the growing of this crop. 
Napier grass responds readily to fertilizer treatments on many 
Hawaiian soils. At the university farm, Manoa Valley, on fields that 
have been under crop rotation and on winch green-manuring crops 
have been grown extensively, experiments now in progress are showing 
a marked response to the addition of nitrogenous and phosphatic 
fertilizers. Data obtained b} 7 Chung at the Hawaii Experiment Sta- 
tion (2, p. 30) show definite increases in yield from the application 
of 450 pounds of sodium nitrate per acre. A demonstration carried 
out through the cooperation of the Agricultural Extension Service of 
the University of Hawaii with a ranch on the Island of Kauai, reported 
by Krauss {5, p. 38), showed remarkable results from the use of 400 
pounds of superphosphate per acre. The fertilized area was ready 
for pasturing in 5 months from the date of planting, while the unfer- 
tilized areas required at least 8 months or more before the cattle could 
be turned into the paddocks. Exact information on the use of fer- 
tilizers for Napier grass is very meager, and further investigations are 
needed on which to base specific recommendations for local areas. 
PREPARATION OF THE SOIL 
Although Napier grass is aggressive and perennial in nature, com- 
peting very well with most weeds, it becomes well established in perfect 
stands only if planted in a thoroughly prepared seed bed. On new 
land or land that has been out of cultivation for some years, several 
plowings may be necessary. The soil should be allowed to aerate 
thoroughly after the first plowing, and it should be disked several 
times to kill as many weeds as possible. This procedure of plowing 
and disking should be repeated once, twice, or more if necessary, in 
order to get the soil in a good physical condition as well as to rid it 
of weeds which will come up after the first plowing. On more improved 
lands it may be that one plowing will be all that is essential. Thorough 
harrowing, however, is bound to pay, for if the plantings are weedy a 
good stand is hard to establish and maintain. Time spent in prepa- 
ration of the soil is usually well repaid in the subsequent ease of 
management and the greater yields obtained. 
METHODS OF PLANTING 
Napier grass is propagated largely by vegetative means, either using 
stalk cuttings or root-clump divisions. Stalk cuttings for planting 
are best secured from a field which has been cut a few months previous 
