THE MACADAMIA NUT IN HAWAII 7 
The lower part of the stems of the seedling is often crooked. It 
has been frequently suggested that this defect can be remedied by 
planting the seed witli the small holelike depression face down. 
This depression in the nut is found directly opposite to the embryo. 
At the station an experiment with 50 nuts faded to indicate that 
position of nuts at planting time influenced the nature of the stem 
developing from the caulicle. In some instances the seed was turned 
completely over by the growing seedling. In other instances the 
stem grew straight although the seed had been planted with embyro 
down. (Fig. 4.) The station observations indicate that crooked- 
stem development is due to the fact that moisture conditions were 
unsuitable at the time the seed was germinating. 
VEGETATIVE PROPAGATION 
Experiments in connection with the vegetative propagation of the 
Macadamia at the station were begun in 1922. Attempts to graft 
seedling trees were made without success at that time, although both 
seedlings growing in the field and in gallon tin containers were used. 
Another unsuccessful attempt was made with young trees during 
1923. A much more extensive experiment was begun by Ralph Molt- 
zau. a student employee of the station, in 1927. He tried branch 
and root cuttings of different forms in different mediums, air 
layering, inarching, budding, and various other kinds of graftage. 
The successes obtained thus far have been with cuttings, air layers, 
inarches, and grafts. 
From a large number of seedlings which were germinated in the 
fall of 1926, 150 were selected as rootstocks for the vegetative propa- 
gation work. The variation in size of seedling seemed to be an un- 
important factor since successes were obtained with stocks which 
ranged from three-eighths to three-fourths inch in diameter. The 
larger sizes were used mainly in inarching where the scion branches 
were correspondingly large. Trees of different sizes and ages in the 
station orchard and in the orchards of cooperative experimenters 
furnished such other material as was needed. 
Results of experiments at the station show that the Macadamia 
may be successfully rooted as cuttings. Factors combining to make 
the process possible are (1) a deep and thoroughly underdrained 
soil in which had become incorporated much organic matter from 
decomposed leaves and other forest litter; (2) a temperature that 
ranges between 65° F. at night and 70° in the daytime; (3) pro- 
tection from the intense heat of the sun at midday by some method 
of shading; and (4) an abundance of moisture. The most successful 
cuttings were made from rather mature branches 1 to 2 feet long 
and one-half inch or more in diameter. Such cuttings develop a 
good root system in three to five months. The new top growth bursts 
forth as tender branches, grows rapidly for a few days, and then 
slows down, and the branches harden preparatory to making another 
period of active growth. The rooted cuttings should be transplanted 
at a time when growth appears to be the most dormant. 
Standardizing varieties of Macadamia as nursery stock by means 
of cuttings may prove to be the most practicable method of large- 
scale propagation. However, this method may not be practicable 
under certain circumstances, as for example when certain desirable 
