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Cultural control, the use of various agricultural practices to make a habitat less suitable insects and for reproduction and/or survival of pests, is a long-established method of pest control. HUMANS

Cultural control aims, therefore, to reduce rather than eradicate pest populations and is typically used in conjunction with other control methods. However, in some instances, cultural practices alone may effect almost complete control of a pest, as occurs with the tobacco hornworm (Manduca sexta) in North Carolina and the pink bollworm (Pectinophora gossypiella) on cotton in central Texas.

The agricultural practices used either may have a direct effect on the pest or may act indirectly by stimulating population buildup of a pest's predators or parasites, or by making plants and animals more tolerant ofpest attack. An essentialprerequisite for effective cultural control is detailed knowledge of a pest's life history so that its most. susceptible stages can be determined. For crops, important agricultural practices include (1) crop rotation to prevent buildup of pest populations; (2) planting or harvesting out of phase with a pest's injurious stage(s), which is especially important against species that have a limited period of infestation or for plants with a short period of susceptibility; (3) use of trap crops on which a pest will concentrate, making its subsequent destruction easy; (4) soil preparation, so as to bury or expose a pest, or increase the crop's strength so that it can more easily tolerate a pest; (5) clean culture, the removal, destruction, or ploughing under of crop remains, in or under which pests may hibernate; and (6) crop diversity, that is, reversal of the current practice of monoculture (growing a single crop over a wide area). Studies have shown that damage to mixed crops or diverse natural vegetation is much less than that done to plants in monoculture. In mixed crops pests may experience greater difficulty in locating their host plant, while the occurrence of diversity may improve the resources available for parasitoids and predators of the pest. [The chapters by Stem, Cromartie, and Brust and Stinner in Pimentel (1991, Vol. 1) provide excellent discussions of the various aspects of cultural control of crop pests.]

Among the strategies available for cultural control of livestock pests are the use of barriers, habitat alteration, pasture rotation, and removal or restriction of alternate hosts (Steelman, in Pimentel, 1991, Vol. 1). Barriers are of two types: (1) areas cleared of vegetation that prevent the pest from invading the area occupied by livestock; this has been used successfully against tsetse flies in east Africa; and (2) areas containing specific vegetation to inhibit or impede entry of pests; for example, along the east coast of the United States, the planting of bushes and grasses around the breeding grounds of the horse fly Tabanus nigrovittatus largely prevented it reaching upland areas occupied by livestock. Examples of habitat alteration are: the selective clearing of low undergrowth adjacent to rivers to allow entry of hot dry winds from the adjacent savannah, thus destroying the humid microclimate preferred by tsetse flies; water impoundment, or drainage of marshes, to destroy mosquito breeding sites; and drainage, harrowing, and liming of pastures to eliminate sheep ticks (Ixodes ricinus). Pasture rotation is the practice of grazing livestock alternately in adjacent pastures, allowing enough time to lapse to ensure that pests such as ticks starve to death. A modification of this strategy is to move livestock among pastures that have seasonal variations in pest levels. Removal or restriction of alternate hosts is sometimes necessary when livestock and wildlife, especially game animals, live side by side. Thus, destruction of game and the building of game-proof fences have been widely used in east Africa to reduce tsetse fly populations, and tall fences have also been effective in reducing the density of ticks in areas of Tennessee by reducing deer populations.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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