Explore key concepts in agricultural weed management, including control methods, crop competition, and strategies for minimizing weed impact in farming systems. Assess your understanding of weed biology and integrated management approaches.
Which of the following is a major reason for correctly identifying weed species in crop fields?
Explanation: Correct weed identification allows a farmer to choose the most effective and targeted control method. Crop diversity is beneficial but not the main reason for weed identification. Soil erosion is a negative effect, not a goal, and attracting more pollinators is unrelated to weed species identification.
What is a common cultural practice to suppress weed growth in agriculture?
Explanation: Crop rotation changes the types of crops grown, disrupting weed lifecycles. Frequent burning can harm soil health and is not widely used. Over-fertilizing may actually benefit weeds, and selectively cutting only weeds is labor-intensive and less practical than integrated strategies.
Why must herbicide application in weed management be carefully timed and dosed?
Explanation: Correct timing and dosing of herbicides minimize the risk of damaging crops. Herbicides are not intended to attract insects, manipulate temperatures, or slow plant growth in general. Misuse can reduce crop yield or cause resistance.
How do weeds negatively impact crop productivity in a field?
Explanation: Weeds compete with crops for essential resources, reducing yields. Most weeds do not improve soil fertility or attract rain, and only a few specific plants fix nitrogen, which is not generally true for all weeds.
Which tool is traditionally used for mechanical weed removal in small-scale farming?
Explanation: A hoe is a handheld tool commonly used for physically removing weeds. Sprinklers irrigate crops, drones are mostly for monitoring or spraying, and seeders are used for planting rather than weed control.
What term is used for the collection of viable weed seeds present in the soil?
Explanation: The seed bank refers to weed seeds stored in the soil waiting to germinate. Root reserve relates to underground plant storage, soil biomass is general organic matter, and leaf litter is decomposing plant material.
Which process describes certain plants releasing chemicals that inhibit the growth of other plants, including weeds?
Explanation: Allelopathy involves plants producing chemicals that impact the growth of neighbors, such as weeds. Hybridization is cross-breeding, nitrification is a soil nitrogen process, and germination is the sprouting of seeds.
What is the main goal of introducing specific insects or diseases to control weed populations?
Explanation: Biological control uses living organisms to reduce weed populations. The goal is not to encourage weed growth, increase pollination, or promote more chemical use.
What practice can help prevent the development of herbicide-resistant weeds?
Explanation: Rotating herbicides with different actions prevents resistance buildup. Using the same product consistently, ignoring dosages, or deliberately growing weeds worsens resistance problems.
What best describes the approach of Integrated Weed Management in agriculture?
Explanation: IWM integrates multiple strategies for effective long-term weed control. Focusing solely on herbicides or cover crops, or removing all plants but crops, is less sustainable and overlooks the benefits of a diverse approach.