Herbicide Adoption Contributed Greatly to Increased Corn Production





Author: Cardwell, V. B.
Affiliation: University of Minnesota, St. Paul.


Dangerous Respirable Dust Increased by Organic Farming in California

Airborne Dust From Cultivation

Airborne Dust From Cultivation

Health effects of breathing dust can be major. When inhaled, small dust particles can travel easily to the deep parts of the lungs and may remain there, causing respiratory illness, lung damage, and even premature death in sensitive individuals. People in California are exposed to unhealthful levels of small dust particles more frequently than to any other air pollutant measured. California farmers have minimized dust emissions by using herbicides to reduce weed populations instead of plowing the dry soil.  However, organic farmers do not use herbicides and cultivate their fields which results in significant increases in respirable dust in California.

“Respirable dust (RD), defined as particles smaller than 4µm diameter, was collected at the implement from 29 farming operations performed for furrow-irrigated tomato, corn, and wheat crop production over a 2-year period. …Among the cropping systems studied, those that required more tillage or land preparation to be performed when the soil was driest produced the most RD.

Cultivation of organically managed corn caused the greatest increase in RD, more than four times baseline.

In the organically grown crops, all operations related to soil structure improvement were performed in the dry fall. The organically grown corn was disked five times and land planed only once in the fall, while the organically grown tomatoes had four disking and three land-planing operations. As a result, the organically grown tomatoes had a much higher RD production. As in 1994, the organically grown crops produced more respirable dust than their conventional counterparts. The RD increase relative to conventionally grown crops ranged from 15% for the organically grown corn to 40% for the organically grown tomatoes.”

Authors: Clausnitzer, H., and M. J. Singer.
Affiliations: Department of Land, Air & Water Resources, UC Davis.
Title: Intensive land preparation emits respirable dust.
Source: California Agriculture. 1997. 51[2]:27-30

Herbicide Use Conserves Water, Tripling Sorghum Yields


Sorghum Yield: Bushland, Texas




Affiliation: USDA-ARS.


Treated vs Untreated

Herbicide Treated (L) vs Untreated (R)

71 - graph





Affiliation: University of Wisconsin and University of Massachusetts.
Title: Biologic & Economic Assessment of Pesticide Usage on Cranberry.

Herbicides Can Help in Making Tibet Food Secure

Farmland in Tibet

Farmland in Tibet

Tibet is isolated from the outside world by physical inaccessibility. Physical remoteness is exacerbated by the lack of roads. However, even though some roads exist, the long distance contributes to remoteness. In such circumstances, to produce enough food within the region and to minimize the dependency of acquiring food through exchange are the essence of food security. Crop yields in Tibet could be much higher. It is suspected that uncontrolled weeds are a major cause of low yields in Tibet and herbicides could be an effective technology to making Tibet food secure.

“In the south of the Tibet Autonomous Region of China there is a network of valleys where intensive agriculture is practiced. Although considered highly productive by Tibetans, farm incomes in the region are low, leading to a range of government initiatives to boost grain and fodder production. … Average yields for the main grain crops are around 4.0 t/ha for spring barley and 4.5 t/ha for winter wheat, significantly lower than should be possible in the environment.

…there is a large gap between attainable yields in Tibet and those that are typically attained on farms in the cropping zone.

There is a need to identify the most important weeds on Tibetan farms and the yield penalties they impose. If weeds do prove to be a significant constraint, as is suspected, a program to improve the availability and affordability of herbicides to Tibetan farmers, and to train farmers in their effective and safe use, should lead to crop yield increases. There is also a need to promote integrated weed management practices that combine cultural and manual control methods with the use of clean seed, targeted rotations, and herbicides.

In recent decades, there has been a major shift around the world towards no-till farming systems, in which weeds are controlled using herbicides before crops are sown into undisturbed soil using no-till seed drills. Such seeding systems would likely offer several benefits in Tibet: viz. lower crop establishment costs (e.g. for fuel and labour), less disturbance to soil structure, less disturbance to levelness of fields, and the option of retaining more stubble without impeding sowing for improved soil health.”

Authors: Paltridge, N., et al.
Affiliation: The University of Adelaide, Australia.
Title: Agriculture in Central Tibet: an assessment of climate, farming systems, and strategies to boost production.
Source: Crop & Pasture Science. 2009. 60:627-639.


Treated vs. Un-treated

Treated (back) vs. Un-treated (front)






Authors: Ransom, J., et al.
Affiliations: North Dakota State University.

The Importance of Pendimethalin Herbicide in Greece


Greek Cotton Field






Authors: Mattas, K., et al.
Affiliations: Aristotle University of Thessaloniki.

Herbicide Use in Spanish Olive Groves Conserves Soil


The actual soil surface is indicated by the continuous black line, while the dashed line indicates the position of the original, eroded soil surface. The difference between both surfaces corresponds to the eroded soil profile.

Weed control in olive groves is necessary to prevent them from competing with the olive trees for moisture. In the 1970s, tillage with tractors became commonplace in Spanish olive groves. However, repeated ploughing left the soil loosened and torrential winter rains washed away the topsoil. Herbicide use has replaced tillage for weed control during the last twenty years and large reductions in soil erosion have occurred. A recent study determined that during the period of mechanical tillage, erosion rates were as high as 40t/ha/year while today, the erosion rate is 10t/ha/year.

“Olive orchards are an important agro-ecosystem in the Mediterranean. Soil erosion is a widely recognized threat to their sustainability. …This study aims at measuring and modelling soil erosion rates in olive orchards over a 250-year period, and relating these to changes in management practices and yield, as documented from historical sources. In three study areas in S-Spain, the height of relic tree mounds was measured in olive orchards dated between 153 and 291 years old to determine soil profile truncation. Historical documents allowed characterizing land management since 1752 in eight distinct periods.

Current soil losses by tillage are low because of the replacement of the spring tillage operations by herbicide application since the start of Period 8 in 2000. Only superficial harrowing is continued during summer. These superficial operations result in a lower movement of soil. In contrast, the highest soil erosion rates by tillage are found right after the introduction of mechanized agriculture, between 1970 and 1990 (Period 7), mainly because of deep mouldboard plowing, which is done at least twice a year.

Most of the tillage erosion occurred during periods of intense tillage, like from 1970 to 1990. To date, tillage is of minor importance due to the preference for herbicide use for controlling weeds.”


Authors: Vanwalleghem, T., et al.
Affiliation: Instituto de Agricultura Sostenible, Spain.
Title: Quantifying the effect of historical soil management on soil erosion rates in Mediterranean olive orchards.
Source: Agriculture, Ecosystems and Environment. 2011. 142:341-351.

Labor Shortages on Indian Tea Plantations Result in Need for Herbicides

Scraping Weeds In Tea Fields

Scraping Weeds In Tea Fields






Authors: Rajkhowa, D. J., et al.
Affiliation: National Research Centre for Weed Science.
Title: Weed management in tea.

Angry Italian Women Replaced by Herbicides


Le Mondine of the 1950s                                                                      Riso Amaro “Bitter Rice”



Authors: Scarabel, L, et al.
Affiliations: National Research Council, Italy.