Template:Chapters 6.10
6.10 - The Benefits of Early Weed Removal
Elisa Dyras , University of Guelph, Canada
Suggested citation for this chapter.
Dyras,E. (2022) The Benefits of Early Weed Removal. In Farmpedia, The Encyclopedia for Small Scale Farmers. Editor, M.N. Raizada, University of Guelph, Canada. http://www.farmpedia.org
Background to Early Weed Removal
In order to ensure crop health and productivity for small-scale farmers, it is essential that weeds are removed early in the growing season to prevent competition with crops (Gardening Australia, 2022). The presence of weeds results in decreased quality crops and lower crop yields in addition to increased production costs during the process (Kumar & Jha, 2017). Various factors including the number of weeds growing, the availability of labour and the effectiveness of each technique, helps determine which weed removal method to use (Bhullar et al., 2015).
Advantages of Timely Weed Removal
Montana State University conducted field experiments to assess the effect of nitrogen rate, seeding rate, and timing of weed removal on weed interference in barley. Montana ranked as the second-largest producer of barley in the United States in 2014, accounting for 25.3% of total production (Kumar & Jha, 2017). While barley thrives in both irrigated and dryland farming environments, delaying weed removal from barley resulted in reduced crop yields. A 10% reduction in barley biomass was observed when the timing of weed removal was postponed from the 3 to 4 leaf stage to the 8 to 10 leaf stage (Kumar & Jha, 2017). This highlights the importance of early weed removal to enhance barley's resilience against weeds. Grain production in maize corresponds significantly with the number of kernels produced per year, which is heavily influenced by plant growth rate (Page et al., 2009). Timely weed control refers to the specific timeframe during which weeds must be effectively managed to avoid reductions in crop yields. During a 2007 experiment at the University of Guelph, Canada, researchers compared maize crops with weeds to those without weeds. The experiment included introducing weeds and then removing them at intervals of 3, 6, 9, and 12 days. The study found that early weed exposure slowed seedling growth and development in maize (Page et al., 2009). As a result, early weed control is crucial to enhancing maize resilience to weeds. Rice serves as the primary food source for approximately 50 percent of the global population (Pratap et al., 2023). During the early stages of growth, weeds compete for nutrients, water, light and space with rice crops (Shukla et al., 2015). As a result of deteriorating soil health and puddling conditions, rice crops require a large amount of labour, energy, and water. During a 2-year study at the Banaras Hindu University in India, the addition of manual weeding during the growing season was discovered to enhance rice yield by approximately 3–19.5% (Shukla et al., 2015). This emphasizes the crucial role of early weed removal in improving the ability of rice to withstand weed invasion.
Research indicates that Africa's low cassava productivity is partly due to inadequate weed management in the first 16 weeks of cassava growth (CGSpace, 2015). If farmers do not control weeds effectively during this period, it can significantly delay cassava root development and reduce yields. As women in African agriculture take on a more prominent role in daily farm activities, adopting efficient weed management techniques becomes vital for optimizing growth and productivity in cassava farming. Rather than receiving sympathy or attention, the recurring challenge faced by African women farmers has become the new normal (CGSpace, 2015). This highlights the importance of increasing awareness and support for these women who play a crucial role in crop production.
How Weeding is Usually Conducted: Herbicide-Based Treatment Versus Machine Weeding
Due to weeds being susceptible to pests and diseases that can then spread to adjacent crops, the weeds must be managed properly using non-chemical or chemical methods (Bhullar et al., 2015). However, the availability or improper use of herbicides for weed management is a significant concern. Research shows postponing chemical treatments or applying it prematurely can detrimentally impact the yield and quality of corn crops (Dalley, Bernards, & Kells, 2006), leading to nutritional imbalances in the soil, reducing crop health and yield.
However, small-scale farmers are unlikely to have access to herbicides. Instead, they utilize labour efficient strategies such as planting in rows for easier monitoring and manually removing weeds by hand or using machinery. Recognized and widely used practices serve as substitutes for herbicide application (Bellamy, 2011). Machine weed treatment, starting with seedbed preparation is considered effective despite being time consuming and labour intensive because it makes growing conditions unfavorable (Bhullar et al., 2015).
Hand weeding is a cost-effective although time-consuming option. For small-scale farmers, employing a finger weeder tailored to their crops provides an effective solution for weed removal without compromising crop integrity. Finger weeders are available in various sizes and typically feature a set of rotating fingers that navigate through the soil between crop rows, uprooting or disrupting weeds while minimizing crop disturbance (Timor Products, 2024).
A corkscrew weeder is an alternative tool designed to target and remove weeds with deep roots. It features a spiral blade connected to a handle, which can be adjusted based on farmers' preferences and the specific requirements of their crops (Kent & Stowe, 2023). This tool's ease of use and low operational effort make it an accessible choice for women farmers engaged in weed removal tasks.
Critical Analysis
First, to be able to visually monitor crops, planting in rows is beneficial for small-scale farmers to be able to catch weed growth and quickly take action (Timor Products, 2024). Finger weeders (see below) are an effective piece of farming equipment, although can be costly for farmers. A more cost-effective alternative is hand weeding, though this option is labor-intensive and time-consuming especially, during adverse weather conditions. Alternatively, farmers have the option to create their own farming equipment, such as a wire weeder. This approach is suitable for weeds with shallow roots that are easy to dislodge (Farmer Keith, 2021). One significant advantage of this do-it-yourself (DIY) approach enables farmers to tailor their tools according to their crops and specific needs. Another benefit is that farmers do not have to rely on manufacturers or suppliers in case their equipment breaks. Instead, utilizing readily available resources such as a broomstick and wire enables small-scale farmers to quickly replace broken equipment. Another practical approach is making a corkscrew weeder (see below). This method is effective at targeting deeper roots and is cost-effective (Kent & Stowe, 2023). While a corkscrew weeder can be purchased, it is an easy do-it-yourself tool that can be constructed out of a spiral blade attached to a broomstick and handle. This method allows farmers to create their own weeding equipment while customizing the length of the tool to fit the crops needs. Like the wire weeder, farmers gain advantages by not depending on manufacturers when equipment malfunctions. Instead, broken equipment is replaced using materials readily available on the farm.
Another thing to consider is women’s crucial role in the removal of weeds from crops is often influenced by cultural norms and gender-associated farming tasks. For instance, women contribute around 90% of hand-weeding efforts in cassava crops across Africa (CGSpace, 2015). This has a considerable impact on preventing significant losses in crop yields due to weeds. The Cassava Weed Management Project aims to transform the lives of women farmers by creating integrated weed management solutions over the course of five years, minimizing labour-intensive weeding and improving farmers’ incomes. Accomplishing the project's goals would significantly improve the livelihoods of African women farmers who contribute significantly to meeting over half of the food needs in developing countries (CGSpace, 2015). Despite their crucial role, women are often underestimated leading to significant long-term effects on their well-being.
Conclusion
In summary, removing weeds before they flower is crucial for small-scale farmers to maintain crop health and enhance productivity. While timely weed removal is crucial to crops, there are tools available to assist the process and make it easier for farmers. Finer weeders are available although might not be suitable for all types of soil or crop conditions. Another option small-scale farmers have is to build their equipment. Wire weeders provide significant advantages as they are easy to build and can be effectively used in various crops promoting sustainable farming practices.
Links to Useful Resources
Home-Made Weeding Tools Small-scale farmers rely on using farming tools such as a finger weeder to reduce labour intensive tasks and increase efficiency (see Figure 1). Farmers can benefit significantly by creating their own equipment, such as a wire weeder, that can effectively remove weeds (see Figure 2). A wire weeder can be made by attaching a broomstick to a bent wire and securing it with hose clamps, making it a simple do-it-yourself (DIY) solution (Farmer Keith, 2021). This DIY method allows farmers to modify their tools to their crops demands and field conditions.
Another option is making a corkscrew weeder by attaching a spiral blade attached to a handle (see Figure 4). By inserting it into the soil and twisting, it efficiently uproots weeds without disturbing surrounding crops, offering an alternative to hand weeding. Additionally, it is useful in areas where manual labour for weeding is expensive, providing a cost-effective solution to weed management (Kent & Stowe, 2023). This DIY allows for customization of the handle length based on the crop's requirements.
Source: https://www.youtube.com/watch?v=wzGJqb5oZn8&t=94s
Source: https://www.youtube.com/watch?v=IreF3UQs6tQ
Source: https://www.youtube.com/watch?v=IreF3UQs6tQ
Source: https://www.amazon.ca/DeWit-Corkscrew-Weeder-Short-Handle/dp/B002FYCIB8?th=1
Further Readings:
Preventative Methods for Weed Management https://www.fao.org/3/y5031e/y5031e0e.htm
Trends In Weed Management https://www.fao.org/3/y5031e/y5031e0j.htm
Recommendations for Improved Weed Management https://www.fao.org/3/a0884e/a0884e.pdf
Helpful videos:
The Importance of Early Weed Control https://www.youtube.com/watch?v=90HhoFhLA
Weed Management for Small Scale Production https://www.youtube.com/watch?v=cIFJ6TXi6WY
Simple Methods to keep Weeds Under Control https://www.youtube.com/watch?v=LypOjugIKQs
Importance of Removing Weeds https://www.youtube.com/watch?v=RIJ8-O8jQ6s
References
1.Bhullar, M. S, Kaur, T., Kaur, S., & Yadav, R. (2015, August 15). Weed management in vegetable and flower crop-based systems. Indian Journal of Weed Science. 47(3), 277–287. https://isws.org.in/IJWSn/File/2015_47_Issue-3_277-287.pdf.
2.Bellamy, A. S. (2011). Weed control practices on Costa Rican coffee farms: is herbicide use necessary for small-scale producers? Agriculture and Human Values, 28(2), 167–177. https://doi.org/10.1007/s10460-010-9261-2
3.CGSpace. (2015, March). Cassava Weed Management. Sustainable Weed Management Technologies for Cassava Systems. International Institute of Tropical Agriculture https://cgspace.cgiar.org/server/api/core/bitstreams/184dfc4c-ac88-4060-a5e7-359a8b7dbca7/content
4.Dalley, C. D., Bernards, M. L., & Kells, J. J. (2006). Effect of Weed Removal Timing and Row Spacing on Soil Moisture in Corn (Zea mays). Weed Technology, 20(2), 399–409. https://www.cambridge.org/core/journals/weed-technology/article/abs/effect-of-weed-removal-timing-and-row-spacing-on-soil-moisture-in-corn-zea-mays/6B0F88296510F4029B3C7403B02EEDFF
5.DeWit Corkscrew Weeder. (n.d). Amazon.ca https://www.amazon.ca/DeWit-Corkscrew-Weeder-Short-Handle/dp/B002FYCIB8?th=1
6.Farmer Keith. (2021, August 19). How to build a Wire Weeder. YouTube. https://www.youtube.com/watch?v=IreF3UQs6tQ
7.Gardening Australia. (2022, December 2). Simple methods to keep weeds under control Gardening Hacks. YouTube https://www.youtube.com/watch?v=LypOjugIKQs&t=89s
8.Kumar, V., & Jha, P. (2017). Influence of Nitrogen Rate, Seeding Rate, and Weed Removal Timing on Weed Interference in Barley and Effect of Nitrogen on Weed Response to Herbicides. Weed Science, 65(1), 189–201. https://doi:10.1614/WS-D-16-00047.1.
9.Page, E. R., Tollenaar, M., Lee, E. A., Lukens, L., & Swanton, C. J.(2009). Does the shade avoidance response contribute to the critical period for weed control in maize (Zea mays)? Weed Research, 49(6), 563–571. https://doi.org/10.1111/j.1365-3180.2009.00735.x
10.Pratap, V., Verma, S. K., & Dass, A. (2023). Weed growth, nutrient removal and yield of direct-seeded rice as influenced by establishment methods and chemical-cum-mechanical weed management practices. Crop Protection, 163, 106100 https://doi.org/10.1016/j.cropro.2022.106100
11.Shukla, U. N., Srivastava, V. K., Singh, S., Ram, U. S., & Pandey, A. K. (2015). Effect of seedlings age, cultivars and weed management on weed dynamics, nutrient removal, and yield of rice (Oryza sativa) under system of rice intensification (SRI). The Indian Journal of Agricultural Sciences, 85(10), 1260–1268. https://doi.org/10.56093/ijas.v85i10.52186
12.Kent & Stowe. (2023, September 21). Stainless Steel Hand Corkscrew Weeder. Garden Health. https://www.gardenhealth.com/stainless-steel-hand-corkscrew-weeder
13.Timor Products. (2024, February 29). High efficiency in-row weed removal - finger Weeder Overview. YouTube. https://www.youtube.com/watch?v=wzGJqb5oZn8&t=94s