12 
permits a continuance of such vital processes as are necessary for the 
success of the union. The grafted plants were kept in a moist slat- 
house to afford them protection from the wind and partial shading 
from the strong sunlight. The scions of these grafts made no visible 
growth for 14 to 28 days. They then grew rapidly. (Fig. 7.) 
After about 40 days the seedling tops were severed at the point 
of union, and the cut surfaces were coated with grafting wax. In 
a few days the grafted trees were transplanted to 12-inch pots to 
make further growth preparatory to their removal from the slathouse 
to the open sunlight. After they have been allowed to remain for 
several weeks in the open to establish a good root system and well- 
hardened branches and foliage, the grafted Macadamia trees may be 
transplanted to their permanent place in the orchard. 
Figure 7. — Various stages in grafting young Macadamia trees 
NATURAL REQUIREMENTS 
CLIMATE 
In climatic requirements the Macadamia tree may be considered 
to be strictly tropical. Turner (19, p. ^), botanist for New South 
Wales, states that the tree is suited to localities where frost does not 
occur. For some years the cultivation of the Macadamia has been 
attempted in parts of France, Florida, and California, but the writer 
has been unable to learn whether the nuts were grown on a commercial 
scale in these places. In Hawaii, the Macadamia may be found 
growing from sea level to an elevation of 2,200 feet, and possibly at 
still higher elevations. On Oahu the trees have done well in localities 
where the annual rainfall is 35 to 50 inches. Several Australian 
publications call attention to the fact that the Macadamia has 
drought-resistant properties which possibly indicate its adaptability 
to semiarid regions. However, experiments and observations in 
