472 WEST AFRICAN FORESTS AND FORESTRY 
been planted at, or thinned out to, a distance of 24 feet between each 
tree. On the poorer soils the distance might no doubt be 18 to 20 
feet, and on the very best probably a distance of 30 feet will not be 
found excessive. Where lime or other manure is available and compara- 
tively cheap, and in some cases heaps of humus from the outskirts of 
villages, it would pay to put this on the land in the late autumn when 
the ashes from the previous crops are being spread on the land. In 
addition to these crops, careful surface cultivation round each Oil 
Palm is essential, not only to prevent the growth of weeds but also 
to keep the aeration of the soil good, prevent the desiccating effects 
of the dry season, and accelerate the growth of the Oil Palm. Besides 
planting these crops by directly paid labour under European super- 
vision, using as many modern labour-saving appliances as possible, 
parts of a plantation could no doubt be let out at a nominal 
rent to the natives, even to some of the labourers, to work it in their 
own time, but only planting such crops as would fit in with the 
rotation and not lead to the impoverishment of the soil. Apparently 
the greatest danger to the tropical soil is to leave it bare for any length 
of time. In the rainy season all the mineral matter and tilth is liable 
to be washed away, and in the dry season fissures are formed in it, 
and if it is at all argillaceous it is liable to be dried out for a depth 
of over 2 feet. Constant covering is thus necessary to ensure the 
growth of the Oil Palm. 
6. DesTRucTION oF OiL Patms.—This is carried out for the 
following purposes: For farming (Onitsha) and making palm 
wine. Sometimes many of these trees are destroyed by fire in 
the Ahoada Okigwi, North Owerri, Afikpo, Abakaliki, Ogaya, and 
Obudu. Grubs, too, are a very frequent source of destruction 
among them. The trees are tapped in the Yoruba country to 
obtain palm wine, but it is not known exactly to what extent this 
reduces the yield of palm oil and kernels. On the whole it is 
harmful, owing to the fact that insect and other pests can obtain 
entrance to the tree through the holes made in tapping it. 
With the steadily rising price of gin the tapping of the Oil Palm is 
increasing annually, resulting in a destruction of many thousand trees 
each year, chiefly in the Obubra and Ikom districts, and to a lesser 
extent by tapping the trees in the Yoruba country. Wherever the 
rainfall does not exceed much over 50 inches and the soil of the 
locality is shallow over laterite or some rock formation, the fires 
become usually an annual occurrence. The Oil Palms which at first 
come up on the clearing of the forests then get burnt, and after 
a few years cease to grow faster than the leaves are burned each year, 
and subsequently die. In a similar way the young seedlings which 
may come up are very easily killed by these annually recurring fires, 
and thus the whole district is impoverished. This process can be 
