Environmental Engineering Reference
In-Depth Information
especially for vegetables. Farmers also claim that intermixture of certain crops is
able to repel some insect pests. The most common method of controlling rodent
pests is by trap, of which there are various kinds. Scarecrows are used to scare off
birds that feed on unharvested crops, especially maize.
Water sources and management
Crop farming is rain-fed. Farmers do, occasionally, use water from nearby streams
for their vegetable farms during dry spells. Rain, streams, wells, boreholes, and
lakes are the sources of water for livestock and domestic use.
Often, moist or seasonally flooded depressions are used for water-loving crops
such as sugarcane all the time, and for vegetables during dry periods. Some
farmers make drainage channels to drain excess water in farms. A few use stone
lining to trap rainwater and to minimize its erosive impact on soils. A common
water conservation practice is mulching, including
proka
. The use of mounds,
especially for yams, is yet another moisture conservation practice.
Harvesting and storage
In all cases, harvesting is done manually by hand, with or without the aid of sim-
ple implements, notably the machete/cutlass and the hoe. The maize cob is pulled
off the stalk by hand. Stubborn ones are cut off by cutlass. Peppers, tomatoes, gar-
den eggs, okro, and virtually all vegetables and condiments are plucked by hand.
The palm fruit is harvested by machete. The harvester does this whiles standing
on the ground if the palm tree is short. If the tree is tall, it is climbed or an impro-
vised platform is used for the purpose of harvesting. The cocoa pod is harvested
by cutting it off from the tree using the machete or by simply squeezing it off by
hand if the pod is within easy reach. Pods occurring at higher levels are plucked
by a tall metal-tipped wooden pole. Cassava and cocoyams are harvested by hold-
ing the stem to pull out the tubers. A cutlass is used to dig out tubers stuck in the
ground. However, in cases where the yam has penetrated deeply into the ground,
the tool most commonly used for harvesting is a metal-tipped wooden pole.
Two aspects of the manner of harvesting yams are particularly favourable for
food security and biodiversity conservation. One is the staggering of the harvest-
ing over a long period. In this practice, only one or two matured tubers on a stem
is/are harvested at a time, with the rest left
in situ
in the ground to be harvested
later. A second aspect is the practice of leaving unharvested small yam nodules in
the ground for them to regerminate in a process that may continue for years.
These and other aspects of yam management, including the practice of live
staking, are particularly well developed in home garden agroforestry systems
in Sekesua-Osonson and other migrant Krobo areas as discussed below.
Regarding storage, a popular practice is the use of wooden barns in the farm or
at home, particularly for maize and cassava. Often freshly uprooted cassava
tubers and, sometimes, those of cocoyam are buried in the ground for storage.
