Theory question 106
Weeds and Weed Control(a) State four ways in which weeds are beneficial to the farmer.
(b) Classify insect-pests into three groups based on their mode of feeding and give two examples of each.
(c) State three ways by which pasture can be made available to cattle.
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(a) Any four: some are used as food or vegetables; some are medicinal; serve as livestock feed; act as cover to reduce erosion; add organic matter when they rot; some are ornamental; serve as mulch.
(b) Biting and chewing insects – grasshopper, beetles, caterpillars, termites; piercing and sucking insects – aphids, cotton stainer, mealybug, mosquito; boring insects – stem borer, weevils, pod borer.
(c) Any three: grazing on natural or established pasture; cut-and-carry (zero grazing/soilage); conserved as hay; conserved as silage.
Two examples are needed for each of the three groups.