# From sea salt to glyphosate salt: a history of herbicide use in France

Bruno Chauvel, Christian Gauvrit, Jean-Philippe Guillemin

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Bruno Chauvel, Christian Gauvrit, Jean-Philippe Guillemin. From sea salt to glyphosate salt: a history of herbicide use in France. Advances in Weed Science, 2022, 40 (special 1), 10.51694/AdvWeedSci/2022;40:seventy-five008. hal-03769152

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# From sea salt to glyphosate salt: a history of herbicide use in France

Bruno Chauvel* , Christian Gauvritb , Jean-Philippe Guilleminac

ª Agroécologie, INRAE, Institut Agro, Univ. Bourgogne, Univ. Bourgogne-Franche-Comté, F-21000 Dijon, France. ᵇ 531, route de Moulin Cheval, F-43140 Saint Victor Malescours, France.

**Abstract:** Herbicide use has deeply changed weed management and cultivation practices in France as well as round the world. However, the use of herbicides is more and more questioned, so that it appeared interesting to us to take stock of herbicide use in France. Since 1913, it has been possible to reconstruct the marketing and withdrawal of all the herbicidal active substances used in cultivated plots. Developed to compensate for the lack of manpower, chemical weed control started at the end of the 19th century with the use of mineral molecules. While copper sulfate can be considered as the first active substance with which technical experiments were carried out, sulfuric acid was the molecule that saw the greatest development because of its efficiency. The discovery of active substances

in the United States and Great Britain during World War II allowed for the development of selective weed control, first for eudicotyledonous plants and then for grasses. In France, a total of 233 active substances have been authorized either alone or in combinations. Active substances have been used for more than 27 years on average, but 2,4-D and MCPA have been used continuously for more than 75 years. The effects of these molecules on the environment and health are responsible for most of the questions about their use. The withdrawal of key molecules could soon call into question the very effectiveness of weed control and perhaps put an end to an agronomic innovation that has been in use for nearly one hundred years.

**Keywords:** active substance; combination; historical use; chemical weed management; herbicide resistance; HRAC groups; herbicide ban; environmental regulation

## 1. Introduction

The history of herbicide use began in France at the end of the 19th century. As in many European countries, various social and economic factors caused a significant decrease of the available workforce for weeding crops from (Bain et al., 2010). As a result, the use of products that destroyed unwanted plants appeared to be one of the crucial solutions for maintaining agricultural production (Fron, 1917). Different pre-existing chemical substances with a potential herbicidal action were tested over time. In non-cultivated areas, sodium arsenite (1907), sodium biphosphate (1920), sodium chlorate and ammonium chlorate (1925) were used to weed paths and yards (Vermorel, 1926). In agricultural areas, from the end of the 19th century, copper sulfate (1896), zinc and iron sulfate (1898), copper and sodium nitrate (1898) and zinc sulfate (1899) made it possible to achieve the first selective weed control (Rabaté, 1927; Vermorel, 1926; Vilcoq, 1899; ).

Copper sulfate was identified as a herbicide by a wine grower – Mr. Bonnet – by accident in 1896. It was the first ever solution studied from practical and technical points of view in France to determine efficient doses and the best application periods (Poubelle, 1898). With the aim of managing high densities of weed species belonging to the Cruciferae family – *Sinapis arvensis* and *Raphanus raphanistrum*, broad-leaved and flat-leaved eudicotyledonous plants –, the effectiveness and the cost of treatments were evaluated for the different crops (Fron, 1917). Despite the development of the first horse-drawn sprayers to facilitate the application of copper sulfate, the very high doses to be applied (30-40 kg ha⁻¹) made the use of this solution unattractive and costly compared to other products.

World War I poison gases and toxic dusts (Guérin, 1921) completed this frightening list of attempts to develop “des poisons des plantes” (plant poisons) (Rabaté, 1927). These first trials and findings were the subject of numerous communications in national and local agricultural journals. The application of some of these products (sodium bisulfate, sodium chlorate, sulfuric acid) was not without a risk for farmers (Carbonière, 1925); sodium arsenite was first compound to be banned in 1915 because of its harmfulness (Truffaut, 1938). The dangerousness of some of these products may explain the continued use of less effective but more flexible and less dangerous substances such as copper nitrate (Fron, 1917).

**Journal Information:**

ISSN - 2675-9462
Website: http://awsjournal.org
Journal of the Brazilian Weed
Science Society

**How to cite:** Chauvel B, Gauvrit C, Guillemin J-P. From sea salt to glyphosate salt: a history of herbicide use in France. Adv Weed Sci. 2022;40[Spec1]:e020220015.
https://doi.org/10.51694/AdvWeedSci/2022.40.seventy-five008

**Approved by:**

Editor in Chief: Anderson Luis Nunes
Associate Editor: Luis Antonio de Avila

**Conflict of Interest:** The authors declare that there is no conflict of interest regarding the publication of this manuscript.

**Received:** February 20, 2022
**Approved:** May 3, 2022

* Corresponding author:
bruno.chauvel@inrae.fr

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This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided that the original author and source are credited.

Copyright: 2022
On a larger scale, sulfuric acid (1913) and sea salt (1924) were used in cultivated fields to control high densities of broad-leaved weeds such as *S. arvensis*, one of the most troublesome weeds at the time (Rabaté, 1927). In the case of sea salt (Dessaisaix, 1925), 375-600 kg of salt per hectare seemed to provide acceptable control of broad-leaved weeds such as Brassicaceae species, but also of other weed species such as *Chenopodium* sp., *Matricaria* sp. and even perennial species such as *Convolvulus* sp. Improvements in the application procedure, the development of spreading equipment and the low cost of the product allowed it to be used until the 1940's. The first tests with sulfuric acid were carried out at the end of the 19th century but failed. However, sulfuric acid at adapted dilutions was tested in the 1910's by an agricultural engineer who gave his name to the method (Rabaté method; Rabaté, 1911). Sulfuric acid was widely used after 1930 and ranked ahead of the other products. Its larger spectrum allowed for the control of a wider range of broad-leaved weeds. It was applied on winter cereals, but also on flax or alfalfa (Rabaté, 1927) and was still in use after world War II. This active substance was tested all over the world to improve its use and better define its spectrum of action (Aslander, 1927).

At the very beginning, the term ‘herbicide’ was used as an adjective to describe a tool used for weed control, e.g., “*une faux herbicide*” (a herbicidal scythe) or “un sel herbicide” (a herbicidal salt). In 1910, an advertisement in a horticultural magazine for a product used for weeding paths referred to the product as a “herbicide”. The term “*désherbant*”, which was widely used in French agronomy books after World War II, is far less used nowadays.

The commercial product Sinox© (DNOC - sodium dinitro-cresulate) was the first major organic chemical herbicide developed in France in 1933. This active substance was sold with a particular focus on *S. arvensis* in winter cereals (Truffaut, Pastac, 1943). Sinox© was conditioned to treat half a hectare to make it user-friendly; “*le procédé Truffaut*” (Truffaut process) was marketed by comparing it with sulfuric acid and other widely used molecules. Application doses were determined for different weed species to improve its efficacy. The success of this product was so great that the Truffaut company even warned about its use on other crops such as sugar beet and flax (Truffaut, 1938).

France is an important agricultural country at the world scale, with a highly diversified crop production on just a little more than 28 million hectares. More than 250 crops are grown in mainland France and in the overseas territories. This crop variability (cotton is the only major crop not cultivated in mainland France or its overseas territories) is partly the reason for the diversity and quantity of herbicides being used. The most widely used pesticides in France are herbicides (46%) (Union des Industries de la Protection des Plantes, 2020). More than 29,300 tons of herbicides have been used in France on average per year over the last decade (Ministère de l'Agriculture et de l'Alimentation, 2021a).

The potential end of the use synthetic pesticides by 2050 in Europe (Billen et al., 2021) will mark the end of the herbicide technology that has deeply changed crop production from agronomic and sociological points of view. The use of these substances has led to numerous advances in weed management and has increased yields while reducing the tediousness of weeding. However, the multiple impacts (agronomic, environmental, health, food, etc.) make the use of these substances hardly acceptable for a future sustainable agriculture. Following on from an article published in 2012 (Chauvel et al., 2012), the objective of this work is (i) to provide quantitative and precise data from 1913 onwards on the use of herbicides in France, and (ii) to put forward hypotheses on the consequences of the latest European policies on weed control. The historical approach was considered particularly relevant because it allows comparing the use of pesticides with the evolution of agricultural practices.

## 2. Materials and Methods

### 2.1 Sources

A database was built from various sources of information. The registration procedure of herbicides was enforced in France only at the end of 1943 (Ministère de l'Agriculture et de l'Alimentation, 1943). However, it was decided to also consider the most important chemical solutions developed before this period in the cases where reliable information was available in the literature. We were allowed to access the registration forms of new herbicides deposited in the 1940's. These data belong to the French Ministry of Agriculture, Food and Fisheries, and have never been used before. For reasons of confidentiality, we are not allowed to disseminate them and can only use the generic data (name of the active substance, registration date). Moreover, we used rare pesticide compendia edited in France (Maison de l'Agriculture, 1937; Institut National de la Recherche Agronomique, 1957) to complete the database. The database was built using Excel software (Microsoft Excel, office 2019); its analysis (pivot table) was conducted using tools proposed by this same software program.

From 1961 onwards, the database was completed by reviewing the issues of the “Index ACTA phytosanitaire” (phytosanitary Compendium) published by ACTA (Association de Coordination Technique Agricole) (Ministère de l'Agriculture et de l'Alimentation, 2021b) every year, except the issues of 1964, 1968, 1971 and 1976. The “Index acta phytosanitaire” is based on data provided by chemical companies every year. It could lead to an underestimated number of commercial products, but has no influence on the number of active substances (ASs) and little influence, if any, on the number of combinations of active substances (CAS). Only ASs present in the chapter “Selective and non-selective herbicides” in the “Index ACTA phytosanitaire” were retained for the present study. Only uses in cultivated fields were considered. Only ASs clearly
used as herbicides at the indicated doses were introduced in the database (sulfosate was considered as a glyphosate salt; therefore, sulfosate and glyphosate were both considered under the name “glyphosate”). Other chemicals such as plant growth regulators (e.g., flurenol), herbicide safeners (e.g., mefenpyr-diethyl) or synergists (e.g., ammonium thiocyanate), were not included in the database. Similarly, ASs or CAs specifically used against algae (e.g., dichlorophen, nabam) and mosses (e.g., calcium cyanamide, quinocamin) were not retained.

## 2.2 Nomenclature

The common names of the ASs and chemical families were those approved by the Weed Science Society of America (Weed Science Society of America, 2021). The internet site of the Compendium of Pesticide Common Names completed the data (https://pesticidecompendium.bpcorg/). The groups of modes of action (HRAC groups) were determined according to the website of The Herbicide Resistance Action Committee (Herbicide Resistance Action Committee; Herbicide Resistance Action Committee, 2021). Each HRAC group was identified by a number (e.g., HRAC 1: inhibition of Acetyl CoA Carboxylase).

## 2.3 Data assessment

The variables contained in the database were as follows: AS name, HRAC group, chemical family, absorption route (shoots, underground parts, or both), targeted weeds (broadleaved or grasses), life cycle (annual or perennial). The number of commercial products was also indicated for each year. The database indicates whether each AS can be used only alone, in combination, or only in combination with (an)other AS(s), as well as the authorized crops (thirty-eight major crops were considered; Annex 1). The database currently contains 12,432 lines and 38,025 data (from 1913 to 2021 included), and each line includes the date for an AS or a CA for a given year.

# 3. Results and Discussion

## 3.1 Availability of active substances and of combinations of active substances

At least 233 ASs have been registered and used in France since 1913 (Annex 2). At the beginning of the 20th century, weed control was first carried out using mineral herbicides (sulfuric acid, sodium chlorate, potassium chloride). In 1944, only three synthetic pesticides (DNOC), dinitrophenol and trichlorophenol) were potentially used as herbicides. MCPA and 2,4-D were the first two officially authorized synthetic ASs in 1946 for winter cereals. A total of sixteen ASs used as herbicides were identified in 1944 (Figure 1). Twenty-one additional ASs had been registered in the first "Index ACTA phytosanitaire" in 1961 (Ministère de l'Agriculture et de l'Alimentation, 2021b).

Considering the new authorizations and withdrawals, a regular increase of about three new ASs per year was observed between 1960 and 1992 (Figure 1). The number of ASs remained stable in the 1990's until 2002. The maximum number of ASs available in a year was observed in 2002 (138 ASs). The European regulation of pesticides in 2003 caused the number of available ASs to decrease (Figure 1). Today the French supply of ASs (91 ASs in 2021) is similar to that of the mid-1980's.

The first CAs were observed as early as 1925. Initially, the low number of CAs (until 1960) could be explained by the low number and the specificity of the different ASs available at the time (Figure 1). After 1960, the registration of new selective ASs with new modes of action – hence wider efficacy spectra – increased the opportunities to propose new CAs (156 in 2002, Figure 1). At the beginning of the 1980's, weed control solutions based on CAs became dominant and still remain significant today. More than 481 CAs were registered over the studied period.

We were able to estimate the number of commercial products starting from 1961, using data provided by the "Index ACTA phytosanitaire". One hundred and thirty to 800 commercial products were potentially available each year in France (data not shown). The commercial offer still remains very high in 2021, with 722 commercial herbicidal products. Glyphosate alone can be provided in the form of more than 130 commercial products. A significant reduction in the commercial supply of glyphosate-based products due to regulatory constraints is observed in 2022, with only 25 products (data not shown).

## 3.2 Composition and evolution of combinations of active substances

The combination of different ASs was at first of great interest in the strategies for managing broader spectra of weed species. Marketing strategies now focus on the combination of two or three ASs (Figure 2) in order to

<figure><img src="image_3.png" /><figcaption>**Figure 1** - Number of active substances (ASs O) and combinations of active substances (CAs ●) registered between 1913 and 2021 considering annual authorizations and withdrawals. All ASs are listed in Annex 2.</figcaption></figure>
control species that have become herbicide resistant (e.g., *Lolium* sp., *Papaver rhoeas*) or naturally difficult to weed by chemical treatment (Umbelliferae). Up to five ASs (MCPA, mecoprop, 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), dicamba, ioxynil) have been used in combination to control weeds in ornamental crops.

The current high number of CAs can be explained by new ASs marketed since 2000 that are only marketed in combinations (halauxifen-methyl, beflutamid, oxadiargyl, etc.), and by the obligation to reduce treatment frequency, which can be achieved by combining ASs – generally 2 or 3 – with broad spectra of action. Additionally, the ban of some ASs that were pivotal for weed control in some crops, has led companies to devise new associations that were not considered before.

The database allowed us to highlight the herbicidal molecules most frequently used in CAs over time (data not shown). Dicamba has been the most frequently used AS in CAs since the mid-1960's. Three other molecules have also been used recurrently: 2,4-D, MCPA, and methylchlorophenoxypropionic acid (mecocrop). Group HRAC 4 (auxin mimics) formed the basis of many CAs available to farmers for almost 50 years. From the 2000's onwards, new ASs – diflufenican (HRAC 12), isoproturon (HRAC 5) and ioxinyl (HRAC 6) – have become important in CAs. Finally, over the last 10 years, diflufenican, iodosulfuron-methyl-sodium (HRAC 2) and florasulam (HRAC 2) have been the main ASs used for weed control in crops to manage resistant weed populations. Unfortunately, these data cannot be linked to quantities per hectare.

### 3.3 Duration of the use of active substances and combinations of active substances

ASs have been used for more than 27 years on average (from 2 to 76 years) (Figure 3a). Twenty-four ASs have been

used for more than 50 years, while 2,4-D and MCPA have been used for 76 years. The ASs with the longest duration of use share several characteristics: few cases of resistance, low levels in groundwater, post-emergence treatment and use on many different crops. The use of HRAC 4 ASs should not be questioned in the near future as they are authorized at least until 2030 (European Commission, 2022).

The period of use of CAs is much shorter – 13 years (Figure 3b). Almost 25% of CAs have been used for less than 5 years. Only four CAs have been marketed for at least 50 years, all based on 2,4-D and MCPA. The shorter use of CAs can be explained by both commercial and agronomic choices.

### 3.4 Authorizations and withdrawals of ASs and CAs

Thanks to the annual publication of the "Index ACTA phytosanitaire", we monitored the introduction of new

<figure><img src="image_4.png" /><figcaption>**Figure 2** - Number of combinations of active substances (CAs) from 1924 to 2021. +: combination of two ASs; ◊: combination of three ASs; ⋆: combination of four ASs; ▲: combination of five ASs; ●: total number of CAs.</figcaption></figure>

<figure><img src="image_5.png" /><figcaption>**Figure 3** - Duration of use (a) of active substances (ASs) and (b) of combinations of active substances (CAs) sorted by five-year classes. Data were calculated for the active substances and combinations withdrawn before 2021. The data take currently authorized molecules into account.</figcaption></figure>
active substances on the market as well as withdrawals (sales bans) each year. In the large majority of withdrawals, farmers were allowed to use the previously purchased stocks for one year. Until the 1990's, the number of new authorized ASs was higher than the number of withdrawn ASs (Figure 4). Then, from the 1970's, the number of new authorizations decreased regularly, slightly more sharply so since the 2000's. After the early 2000's, the number of new ASs did not offset withdrawals. The high number of withdrawals in the early 2000's is largely due to the re-evaluation of pesticides in Europe that started in 1991. Only seven new ASs have been registered in the last decade.

## 3.5 Evolution of chemical families and HRAC groups

The increase of the number of ASs was favoured by the development of new chemical families. Herbicide molecules used in France can be classified in 48 different chemical families (Annex 2). The number of families remained limited from 1913 to 1952, but increased afterwards until the 1980's. From 1987 to 2017, at least 40 (40 to 45) chemical families were regularly used, and then the number started to decline.

Knowledge of the modes of action of ASs has become essential for the development of sustainable weed management strategies, particularly to manage herbicide-resistant weed populations. Before 1944, only three groups of modes of action (HRAC 0: unknown; HRAC 6: Inhibition of photosynthesis - PS II - histidine 215; HRAC 24: uncouplers) were available (Figure 5). The other modes of action appeared over time until 1994, and reached a total of 22 (Figure 5).

Different modes of action have been used in France over long periods of time, from 28 years (HRAC 27) to 76 years (HRAC 4). Seven modes of action (6, 10, 18, 19,

<figure><img src="image_6.png" /><figcaption>**Figure 4** - Number of new active substances (Ass) registered (white) and withdrawn (black) per ten-year period.</figcaption></figure>

22, 24 and 34) have been withdrawn (Figure 5). HRAC 10 (glufosinate-ammonium) and HRAC 22 (paraquat) were the latest groups to be withdrawn, resulting in a significant reduction in the supply of non-selective ASs. For other groups such as HRAC 5 (inhibition of photosystem II), the number of authorized molecules is now limited to 7 molecules that are used less and less despite their agronomic role in the management of resistant or new grass weed species (chlorotoluron, metobromuron) or in global weed management in crops such as sugar beet (Beta vulgaris). The latest authorized mode of action was HRAC 27 (inhibition of hydroxyphenyl pyruvate dioxygenase; Figure 5); the main AS of this group is sulcotrione.

## 3.6 Practical and technical uses of active substances

The field use of herbicides is linked to several characteristics. Among the most important points, the level of specificity (weed spectrum) according to the main botanical groups – eudicotyledonous and graminoid plants – is essential to the choice of the AS.

Historically speaking, ASs such as sulfuric acid, dinitrophenol, MCPA were the main ASs used on eudicotyledonous plants until the 1950's (Figure 6). The marketing of efficient ASs on perennial and annual grass weeds -bardan in the mid-1960's, then flamprop and diclofop-methyl in the 1970's - made it possible to considerably increase the control of weed species

<figure><img src="image_7.png" /><figcaption>**Figure 5** - Registration of the different modes of action over time. The black bars in the histogram indicate how long the mode of action has been used.</figcaption></figure>
such as *Elytrigia repens*, *Avena fatua* or *Alopecurus myosuroides* (Figure 6). Broad-spectrum ASs (efficient on eudicotyledonous and graminoid plants) are currently the group from which the greatest number of ASs has been withdrawn from the market; this contributes to weed control difficulties in the field (Figure 6).

The application period is another major characteristic of ASs. The number of ASs used in pre-emergence or pre-post emergence has declined since 2003 (Figure 7), at least partly explained by the European political willingness to protect water quality. These ASs were sprayed on soils with a low plant cover and often persisted in the environment. Post-emergence ASs, which currently

represent two thirds of available ASs (Figure 7), are mainly present in chemical families such as sulfonylureas (HRAC 2: inhibition of acetolactate synthase; 23 ASs in 2021) and aryloxyphenoxy-propionates (HRAC 1: inhibition of Acetyl CoA carboxylase; 10 ASs in 2021). However, these ASs belong to the chemical families most concerned by weed control problems linked to the development of herbicide resistance.

## 3.7 Herbicide resistance

Herbicide resistance was first observed in France in 1978 (Figure 8) in maize and vineyards, with the classic chloroplastic resistance to triazines (HRAC 5; Gasquez et al., 1982). The first plants resistant to aryloxyphenoxy-propionate (HRAC 1) and then to sulfonylurea (HRAC 2) ASs were identified only one decade later (Figure 8), mainly on *A. myosuroides* and then on various other grassweeds (*Lolium* sp., *Avena* sp.; (Research and Reflection Ring on Pesticide Resistance, 2018). Eudicotyledonous weeds (*Ambrosia artemisiifolia*; *P. rhoeas*) became a source of acetolactate synthase (HRAC 2) resistance (Délye et al., 2020; Research and Reflection Ring on Pesticide Resistance, 2018). The latest case of herbicide resistance (2019) was by *Lolium* sp. and concerned a new mode of action (HRAC 15: inhibition of very-long-chain fatty acid synthesis). In France, 22 weed taxa resistant to six modes of action have been identified to date, with different

<figure><img src="image_8.png" /><figcaption>**Figure 6** - Time course of the number of registered actives substances (ASs) according to their weed spectrum. ■: broad-spectrum herbicides; +: ASs against graminoid species; □: ASs against eudicotyledonous species.</figcaption></figure>

<figure><img src="image_9.png" /><figcaption>**Figure 7** - Time course of the number of available actives substances (ASs) according to their agronomic use. △: pre-emergence ASs; ×: post-emergence ASs; ▲: pre- and post-emergence ASs.</figcaption></figure>

<figure><img src="image_10.png" /><figcaption>**Figure 8** - Number of active substances (ASs) for which resistant weeds have been identified according HRAC groups. HRAC 1: inhibition of Acetyl CoA carboxylase; HRAC 2, inhibition of acetolactate synthase; HRAC 4: auxin mimics; HRAC 5: inhibition of photosynthesis at the level of PSII - Serine 264 binders; HRAC 9: inhibition of enolpyruvyl shikimate phosphate synthase; HRAC 15: inhibition of very-long-chain fatty acid synthesis.</figcaption></figure>
levels of agronomic importance (Research and Reflection Ring on Pesticide Resistance, 2018).

The potential withdrawal of some ASs belonging to chemical families not concerned by herbicide resistance, such as prosulfocarb and propyzamide, has become a major concern for farmers in the management of grass weeds. Hormone-type ASs (HRAC 4) without herbicide resistance still provide effective solutions for farmers to control eudicotyledonous weed species.

## 3.8 Availability of herbicidal molecules depending on the crop

### 3.8.1. Comparison of two crops

The dataset was used to follow the availability of ASs and CAs crop by crop. From the beginning of the 20th century, winter wheat was the crop on which the first mineral molecules were tested (sulfuric acid, copper sulfate, etc.), and then the first organic molecules (DNOC, 2,4-D, etc.). Then, chemical weeding of wheat was mainly based on numerous CAs from the end of the 1970's (> 80 CAs in the 1990's; Figure 9) and until 2021 (47 CAs). The number of available ASs has been stable since the early 1990's and has remained high (27 ASs; Figure 9) despite EU regulations.

In the case of vineyards (Figure 9), the situation is different. Since the beginning of the 1960's, chemical weed control has been carried out with a lower number of ASs (15 - 20) compared to wheat, and a smaller number of CAs answers to reach less than 20 chemical solutions today. Vineyard is sometimes referred to in France as the first major crop on which no more herbicide could be used in the coming years.

### 3.8.2. Diversity of the modes of action for different main crops over time

A measure of the diversity of ASs used over time can help estimate the possibilities of chemical weed control for a given crop (wheat, maize, rice, rapeseed, soybean, sunflower, potato, sugar beet, carrot, vineyard).

For field crops (wheat, maize, rice, rapeseed, soybean, sunflower, sugar beet, vineyard), the number of ASs increased until 1990-2000 (Table 1). This increase was associated with the enhancement of modes of action (MoA). The number of ASs and MoA still remains high for these crops. However, this diversity has been reduced by the presence of resistant plants that reduce the range of solutions available to farmers in the field.

Rice is a highly developed crop worldwide; its area of production in France is very small (< 14,000 ha), but the number of authorized herbicides is proportionally high (eight ASs in 2021) (Table 1). Weed control of this crop is more complex because of the habitats and botanical proximity of certain weeds with the crop; the use of chemical weeding remains frequent.

<figure><img src="image_11.png" /><figcaption>Figure 9 - Time course of the number of available chemical solutions for winter wheat (O: ASs; ●: CAs) and vineyard (□: ASs; ■: CAs).</figcaption></figure>

For vegetable crops (potato and carrot), AS and MoA availability increased until 2010-2020 (Table 1). The highest MoA/AS ratio was observed for these crops. This situation is interesting for resistance management because it enables farmers to use ASs with different MoAs.

The reduction of the range of solutions seems to be greatest from an overall point of view. However, the authorization of ASs already registered for other crops has made it possible to maintain a certain number of solutions. Nevertheless, this can result in the use of a same mode of action during a rotation despite the use of different ASs; it implies that the same selection pressure is exerted each year, with a high risk of resistance selection.

## 4. Discussion

This intensive use of pesticides including herbicides is now being questioned by a large part of society. The use of herbicides in France since the 1960's has many consequences on the environment (water and air contamination, reduction of biodiversity in the agrosystems and environments connected to the cultivated fields; (Detoc, 2003); (Schiavon et al., 1995), health (recognition of professional diseases, (Institut National de la Santé et de la Recherche Médicale, 2021) and crop management (herbicide resistance; Research and Reflection Ring on Pesticide Resistance, 2018).

### 4.1 History of herbicide use

The database used in the present review provides an interesting tool for a better understanding of the historical evolution of herbicide use in France. It makes it possible to replace the history of all these molecules in relation to each other, all together or crop by crop.

Before the 1940's French agronomic research was at the forefront of the development of the first chemical weed
<table><caption>Table 1 - Diversity in terms of numbers of active substances (AS), modes of action (MoA) and chemical families (Family) for ten of the main crops in France over 10-year time steps (* 1984; ** 1965; *** 1963).</caption><thead><tr><th></th><th></th><th>1951</th><th>1961</th><th>1971</th><th>1981</th><th>1991</th><th>2001</th><th>2011</th><th>2021</th></tr></thead><tbody><tr><td rowspan="3">Total</td><td>AS</td><td>15</td><td>32</td><td>72</td><td>101</td><td>131</td><td>131</td><td>105</td><td>91</td></tr><tr><td>MoA</td><td>4</td><td>10</td><td>13</td><td>16</td><td>21</td><td>21</td><td>20</td><td>16</td></tr><tr><td>Family</td><td>6</td><td>15</td><td>25</td><td>36</td><td>42</td><td>44</td><td>41</td><td>38</td></tr><tr><td rowspan="3">Wheat</td><td>AS</td><td>8</td><td>8</td><td>16</td><td>19</td><td>27</td><td>27</td><td>26</td><td>27</td></tr><tr><td>MoA</td><td>4</td><td>3</td><td>7</td><td>9</td><td>13</td><td>13</td><td>11</td><td>12</td></tr><tr><td>Family</td><td>5</td><td>4</td><td>7</td><td>9</td><td>13</td><td>16</td><td>13</td><td>15</td></tr><tr><td rowspan="3">Maize</td><td>AS</td><td></td><td>2</td><td>10</td><td>20</td><td>22</td><td>28</td><td>26</td><td>25</td></tr><tr><td>MoA</td><td></td><td>1</td><td>4</td><td>7</td><td>8</td><td>10</td><td>8</td><td>9</td></tr><tr><td>Family</td><td></td><td>1</td><td>5</td><td>8</td><td>11</td><td>15</td><td>13</td><td>12</td></tr><tr><td rowspan="3">Rice</td><td>AS</td><td></td><td>2</td><td>6</td><td>7</td><td>6</td><td>9</td><td>7</td><td>8</td></tr><tr><td>MoA</td><td></td><td>2</td><td>4</td><td>4</td><td>6</td><td>6</td><td>4</td><td>4</td></tr><tr><td>Family</td><td></td><td>2</td><td>4</td><td>4</td><td>6</td><td>7</td><td>6</td><td>6</td></tr><tr><td rowspan="3">Rape seed</td><td>AS</td><td></td><td>3</td><td>4</td><td>11</td><td>18</td><td>18</td><td>13</td><td>18</td></tr><tr><td>MoA</td><td></td><td>3</td><td>3</td><td>5</td><td>7</td><td>10</td><td>8</td><td>10</td></tr><tr><td>Family</td><td></td><td>2</td><td>3</td><td>8</td><td>10</td><td>10</td><td>9</td><td>12</td></tr><tr><td rowspan="3">Soybean</td><td>AS</td><td></td><td>-</td><td>-</td><td>4*</td><td>13</td><td>11</td><td>12</td><td>13</td></tr><tr><td>MoA</td><td></td><td>-</td><td>-</td><td>3*</td><td>4</td><td>6</td><td>7</td><td>7</td></tr><tr><td>Family</td><td></td><td>-</td><td>-</td><td>4*</td><td>7</td><td>7</td><td>9</td><td>9</td></tr><tr><td rowspan="3">Sunflower</td><td>AS</td><td></td><td>2</td><td>3</td><td>3</td><td>12</td><td>12</td><td>10</td><td>13</td></tr><tr><td>MoA</td><td></td><td>2</td><td>2</td><td>2</td><td>7</td><td>6</td><td>7</td><td>8</td></tr><tr><td>Family</td><td></td><td>2</td><td>2</td><td>2</td><td>9</td><td>9</td><td>9</td><td>11</td></tr><tr><td rowspan="3">Potato</td><td>AS</td><td></td><td>1**</td><td>5</td><td>6</td><td>10</td><td>9</td><td>12</td><td>12</td></tr><tr><td>MoA</td><td></td><td>1**</td><td>2</td><td>2</td><td>4</td><td>5</td><td>8</td><td>7</td></tr><tr><td>Family</td><td></td><td>1**</td><td>5</td><td>5</td><td>10</td><td>9</td><td>11</td><td>11</td></tr><tr><td rowspan="3">Sugar beet</td><td>AS</td><td></td><td>1***</td><td>6</td><td>12</td><td>17</td><td>19</td><td>15</td><td>15</td></tr><tr><td>MoA</td><td></td><td>1***</td><td>2</td><td>5</td><td>5</td><td>6</td><td>5</td><td>6</td></tr><tr><td>Family</td><td></td><td>1***</td><td>4</td><td>10</td><td>10</td><td>11</td><td>11</td><td>11</td></tr><tr><td rowspan="3">Carrot</td><td>AS</td><td>1</td><td>3</td><td>5</td><td>6</td><td>8</td><td>6</td><td>9</td><td>13</td></tr><tr><td>MoA</td><td>1</td><td>3</td><td>3</td><td>3</td><td>5</td><td>2</td><td>6</td><td>9</td></tr><tr><td>Family</td><td>1</td><td>2</td><td>5</td><td>4</td><td>5</td><td>3</td><td>8</td><td>10</td></tr><tr><td rowspan="3">Vineyard</td><td>AS</td><td></td><td>6</td><td>8</td><td>12</td><td>17</td><td>20</td><td>17</td><td>15</td></tr><tr><td>MoA</td><td></td><td>4</td><td>5</td><td>9</td><td>12</td><td>13</td><td>11</td><td>9</td></tr><tr><td>Family</td><td></td><td>5</td><td>6</td><td>10</td><td>14</td><td>16</td><td>14</td><td>12</td></tr></tbody></table>
control practices (copper sulfate, sulfuric acid, DNOC). Later on, solutions were brought by research from other countries. The introduction of herbicidal molecules in France more than 70 years ago deeply changed weed management practices. On the one hand, herbicidal molecules greatly reduced the tediousness of agricultural work, which was still largely done by hand or mechanical tools before the advent of herbicides. In the 1960's, herbicidal molecules also enabled the development of new crops (e.g., maize), and the extension of diversified rotations (Sebillotte, 1969) with a better control of perennial weed species. Soil tillage and rotations that allowed alternation of ASs constituted the cornerstone of integrated weed management (Swanton, Weise, 1991; Chikowo et al., 2009). The first congresses 'Journées d'études sur les herbicides' [Study days on herbicides] organized in France in collaboration with the European Weed Research Society in 1961 and 1963 showed the extent of numerous trials aimed at finding molecules that could meet the needs of each crop. In the mid-1970's, the first herbicides against annual grass weeds were proposed to farmers, and allowed the first efficient chemical control of weeds such as A. fatua (diclofop-methyl) and A. myosuroides (isoproturon) described as the number-one weed in France since 1960 (Barralis, 1961). Although herbicide resistance was only observed relatively late (1978) in France (Darmency, Gasquez, 1990), changes in the composition of weed communities were quickly observed, particularly when herbicide use was linked to the reduction of soil tillage (Récamier, 1969). Presently, the management of herbicide-resistant grass weed species is a major problem for cereal farmers who do not have sufficient crop diversity in their rotation. Lolium sp. is a major problem due to multiple resistances (Duhoux et al., 2017), and some ASs like prosulfocarb and propyzamide have become the last chemical solutions for many farmers. The possible withdrawal of these last ASs would make it almost impossible to implement a weed control strategy solely based on chemical weed control.

Since 2012 and the first publication based on the database (Chauvel et al., 2012), seven new ASs belonging to four HRAC groups have been authorized (Table 2), while 20 ASs belonging to 17 different HRAC groups have been

withdrawn. Some of these molecules (diclofop-methyl, isoproturon, oxadiazon) were used on a wide range of crops. No new mode of action has been introduced since 1994.

## 4.2 The case of glyphosate

The use of glyphosate is now widely questioned by a large part of French society. In France, glyphosate currently represents the symbol of intensive agriculture, which is rejected because of its potential effects on health (Institut National de la Santé et de la Recherche Médicale, 2021). With more than 8,000 tons year⁻¹ used in France over the 2018-2020 period (Ministère de la Transition Écologique, 2021), this molecule has become an emblem of the struggle against pesticides to the point that the highly politicised debate leaves little space for scientific arguments. This AS is the only broad-spectrum one still in use today in France after the withdrawal of atrazine (2003), paraquat (2007), amitrole (2016) and glufosinate (2018). Its use remains essential for the management of perennial weed species during the intercropping period and for the management of herbicide-resistant grass weeds. This withdrawal could also completely challenge the development of conservation agriculture in which management of annual grasses and perennial broadleaved plants depends to a large extent on this molecule (Derrouch et al., 2020). Specific studies are still being carried out to try and limit its use by determining maximum authorized annual doses for different crops. All the farms of the INRAE research institute and state agricultural colleges are committed to a complete withdrawal of glyphosate in 2022.

## 4.3 "Natural" herbicides or bioherbicides

The intensive use of synthetic herbicides is questioned for several reasons (risks for the environment, health). As biocontrol has not had any effective development in the field for the moment, bioherbicides could offer an alternative to synthetic herbicides and a number of potential benefits such as rapid degradation in the environment. Despite efforts to identify effective bioherbicides, few solutions are currently

<table><caption>**Table 2** - New actives substances (ASs) authorized during these last ten years (2012-2021). SS: used alone; SA: used alone and in combination; AA: only used in combination. Post: post treatment; pre/post: pre or post treatment. Dicots: eudicotyledonous plants; monocots: graminoid plants.</caption><thead><tr><td>Active substance</td><td>HRAC Group</td><td>Registration Year</td><td>Treatment</td><td>Target weed</td><td>Use</td></tr></thead><tbody><tr><td>Pelargonic acid</td><td>0</td><td>2012</td><td>post</td><td>Broad spectrum</td><td>SS</td></tr><tr><td>Aminopyralid</td><td>4</td><td>2012</td><td>post</td><td>All dicots</td><td>AA</td></tr><tr><td>Pinoxaden</td><td>1</td><td>2012</td><td>post</td><td>Annual monocots</td><td>SA</td></tr><tr><td>Thiocarbazone-methyl</td><td>2</td><td>2013</td><td>pre/post</td><td>Annual weeds</td><td>AA</td></tr><tr><td>Halosulfuron-methyl</td><td>2</td><td>2017</td><td>post</td><td>Broad spectrum</td><td>SS</td></tr><tr><td>Halauxifen-methyl</td><td>4</td><td>2018</td><td>post</td><td>Annual dicots</td><td>AA</td></tr><tr><td>Caprylic acid</td><td>0</td><td>2020</td><td>post</td><td>Broad spectrum</td><td>SS</td></tr></tbody></table>
available on the market (Cordeau et al., 2016). After having
disappeared for more than 40 years, three so-called ‘natural’
molecules are now authorized in France, and are available
to farmers. These new ASs (pelargonic acid, acetic acid and
caprylic acid; HRAC 0) are broad-spectrum ASs. Pelargonic
acid in particular is presented as a potential alternative to
glyphosate. However, many technical adjustments are still
necessary (Travlos et al., 2020) before this type of AS can be
considered as a real alternative in the field. Moreover, the
user cost of this molecule over large areas is still prohibitive.

5. Conclusion: what is the future of synthetic herbicides?

Pesticide use has regularly increased in France since the
1950's: France is the seventh largest pesticide user in the
world, and the first one in Europe (https://fr.statista.com/
infographie/15061/consommation-pesticides-en-europe-
par-pays/). On an amount-per-area basis, it ranks seventh
in Europe with 3.7 kg of active substance ha⁻¹ year⁻¹. Intense
debates are currently going on about the short- and long-
term effects of pesticides, and two subjects are particularly
taken up by the media: the use of neonicotinoids in relation
to honey bees (Apis mellifera) mortality and the use of
glyphosate. As in the case of triazine herbicides about 20
years ago (Mahé et al., 2020), the debate on glyphosate use is
dividing society and the agricultural community. Moreover, it
is more particularly the use of all herbicides that is currently
being questioned. The French “Grenelle de l’Environnement”
in 2007, a national public round table, was conducted to
reduce (if possible) by half the use of pesticides over a
period of 10 years. The “Ecophyto 2018” plan (Ministère de
l’Agriculture et de la Pêche, 2018), which aimed to remove
the products considered most worrying, did not /reach the
proposed objectives. The effort to reduce the use of pesticides
was maintained through the implementation of new plans
“Ecophyto II” and then “Ecophyto II+”, which aimed at
i) a 25% reduction in 2020 based on the optimization of
production systems, ii) an additional 25% reduction in 2025,
which will be possible through major changes in production
systems and the farming sector, and iii) the support of
farmer networks towards agroecology. In 2009, the Ecophyto
Plan aimed to reduce the use of pesticides by 50% by 2018
in France. Then, this objective was postponed to 2025. In
spite of significant fundings, the reduction in pesticide use
did not reach the expected level. However, the Ecophyto
plan sent a strong signal, which undoubtedly announced the
end of the use of herbicides in agriculture as a basic strategy
(Guichard et al., 2017).

To measure the evolution of pesticide use, various
indexes were proposed, such as the Phytosanitary
Treatment Frequency Indicator (TFI: number of reference
doses used per hectare during a crop year) or the Number of
Dose Units (NODU; Hossard et al., 2017). Thanks to these
indicators, a trend towards a decrease in the overall use of
pesticides is confirmed with the lowest three-year average
for 10 years (- 5.7% between 2017-2019 and 2018-2020)

but the interpretation of these tendencies is still debated.
Currently, the attention is paid to chloroacetanilide ASs
(e.g., metolachlor, metazachlor) which has become an
important issue due to the pollution of water resources.

The question today is whether there is still a place for
synthetic ASs within the framework of “agroecological
agriculture” as desired in France (https://agriculture.gouv.
fr/les-fondements-de-lagro-ecologie (Caquet et al., 2019). In
1969, French agronomists considered that the use of these
new herbicides would offer the possibility to introduce new
crops in rotations (Sebillotte, 1969). More than 50 years
later, this same diversification of rotations is considered as
one of the best tools to limit the use of chemical treatments
(Mahaut et al., 2019). Without being contradictory, these two
approaches show the difference that has emerged in the weed
management approach. According to the agricultural extension
institutes, under favourable conditions, the introduction of
mechanical weeding in straw cereals could increase the cost
by at least 10€/ha compared to an “all chemical” strategy, the
labour time being at least 3 times higher. If soil tillage and
other new weed control techniques (robotics, electricity, laser,
natural molecules) do not prove sufficiently effective in some
agronomic situations, can we still consider keeping certain
synthetic molecules for weed management in crops and during
the intercropping period? Based on what criteria would it
be possible to keep a certain number of strategic synthetic
ASs? For certain synthetic molecules such as glyphosate, the
question seems to be clear-cut (at least in France), but nothing
is clearly explained yet for the other synthetic ASs. The effects
of climate change (Ziska, 2020; Storkey et al., 2021) on the
dynamics of weed communities or on the development of
new species (Chadha et al., 2020) will also certainly influence
policy-making. Will it be possible to determine weed species,
crops or cropping systems for which the highly regulated use of
synthetic herbicides will still be possible for agronomic, health
or economic reasons? Agronomic considerations may not
always be considered, while it is acceptable that proven health
risks take priority over a weed management issue in the field.

Author's contributions

BC and J-PG: Conceptualization of the manuscript and
development of the methodology, data interpretation, writing,
review editing. CG: Data interpretation, review editing.

Funding

This research work received no external funding.

Acknowledgments

The authors thank Jacques Gasquez and the agencies
(ACTA) and ANSES (French agency for Food, Environmental
and Occupational Health Safety) for their help. We thank
Luc Biju-Duval for his assistance in data input and Mrs
Annie Buchwalter for her help in reviewing the manuscript.
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Union des Industries de la Protection des Plantes – UIPP. [Our figures: 2020 update]. Paris: Union des Industries de la Protection des Plantes; 2020[access Dec 1, 2021]. French. Available from: https://www.uipp.org/app/uploads/2021/03/Nos-donnees-chiffrees.pdf.

Vermorel V. [Practical manual for weed control]. 2nd ed. Villefranche: Librairie Agricole de la Maison Rustique; 1926. French.

Vilcoq A. [Destruction of harmful cruciferous species]. La Nature. 1899;1368:171-2. French.

Weed Science Society of America - WSSA. List of herbicides: WSSA herbicide site of action (SOA) classification list 2021. Westminster: Weed Science Society of America; 2021[access Dec 1, 2021]. Available from: https://wssa.net/wssa/weed/herbicides/

Ziska LH. Climate change and the herbicide paradigm: visiting the future. Agronomy. 2020;10(12):1-10. Available from: https://doi.org/10.3390/agronomy10121953
Annex 1 - Crops considered in the data base

<table><thead><tr><td>Crop</td></tr></thead><tbody><tr><td>Banana</td></tr><tr><td>Barley</td></tr><tr><td>Carrot</td></tr><tr><td>Cereals (other than wheat and barley)</td></tr><tr><td>Flax</td></tr><tr><td>Fodder grasses</td></tr><tr><td>Fodder legumes</td></tr><tr><td>Forestry crops</td></tr><tr><td>Hops</td></tr><tr><td>Intercropping cover</td></tr><tr><td>Legumes</td></tr><tr><td>Maize</td></tr><tr><td>Maize (tolerant)</td></tr><tr><td>Medicinal crops</td></tr><tr><td>Millet & moha</td></tr><tr><td>Miscanthus</td></tr><tr><td>Mustard</td></tr><tr><td>Orchard</td></tr><tr><td>Ornamental crops</td></tr><tr><td>Pineapple</td></tr><tr><td>Poppyseed oil</td></tr><tr><td>Potato</td></tr><tr><td>Rape seed</td></tr><tr><td>Rape seed (tolerant)</td></tr><tr><td>Rice</td></tr><tr><td>Sorghum</td></tr><tr><td>Soyabean</td></tr><tr><td>Strawberry</td></tr><tr><td>Sugar cane</td></tr><tr><td>Sugar beet</td></tr><tr><td>Sunflower</td></tr><tr><td>Sunflower (tolerant)</td></tr><tr><td>Switchgrass</td></tr><tr><td>Tobacco</td></tr><tr><td>Tropical crops (other than banana and sugar cane)</td></tr><tr><td>Vegetable crops</td></tr><tr><td>Vineyard</td></tr><tr><td>Wheat</td></tr></tbody></table>
Annex 2 - Start: first year of registration; End: year of withdrawal; -: still in use

<table><thead><tr><td>Start</td><td>End</td><td>Active substances</td><td>HRAC</td><td>Chemical family</td></tr></thead><tbody><tr><td>1913</td><td>1979</td><td>sulfuric acid</td><td>0</td><td>Non-classified</td></tr><tr><td>1925</td><td>1930</td><td>potassium chloride</td><td>0</td><td>Non-classified</td></tr><tr><td>1925</td><td>1958</td><td>sodium chlorate</td><td>0</td><td>Non-classified</td></tr><tr><td>1933</td><td>1997</td><td>DNOC</td><td>24</td><td>Dinitrophenols</td></tr><tr><td>1944</td><td>1990</td><td>Na Chlorate</td><td>0</td><td>Mineral salts</td></tr><tr><td>1944</td><td>1960</td><td>calcium cyanamide</td><td>0</td><td>Mineral salts</td></tr><tr><td>1944</td><td>1965</td><td>Dinitrophenol</td><td>24</td><td>Dinitrophenols</td></tr><tr><td>1944</td><td>1960</td><td>copper nitrate</td><td>0</td><td>Mineral salts</td></tr><tr><td>1944</td><td>1950</td><td>zinc nitrate</td><td>0</td><td>Mineral salts</td></tr><tr><td>1944</td><td>1950</td><td>aluminium sulfate</td><td>0</td><td>Mineral salts</td></tr><tr><td>1944</td><td>1950</td><td>copper sulfate</td><td>0</td><td>Mineral salts</td></tr><tr><td>1944</td><td>1950</td><td>iron sulfate</td><td>0</td><td>Mineral salts</td></tr><tr><td>1944</td><td>1956</td><td>Trichlorophenol</td><td>6</td><td>Organochlorine</td></tr><tr><td>1945</td><td>1972</td><td>potassium ethylxanthate</td><td>0</td><td>Carbamate</td></tr><tr><td>1946</td><td>-</td><td>2,4-D</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1946</td><td>-</td><td>MCPA</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1946</td><td>1962</td><td>pentachlorophenol</td><td>6</td><td>Organochlorine</td></tr><tr><td>1947</td><td>1950</td><td>sodium hyponitrite</td><td>0</td><td>Mineral salts</td></tr><tr><td>1949</td><td>1987</td><td>2,4,5-T</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1949</td><td>1991</td><td>petroleum-based oils</td><td>0</td><td>Non-classified</td></tr><tr><td>1950</td><td>1965</td><td>dinoseb</td><td>24</td><td>Dinitrophenols</td></tr><tr><td>1952</td><td>1957</td><td>seasone</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1954</td><td>1962</td><td>cryptophenol</td><td>24</td><td>alkylphenol</td></tr><tr><td>1954</td><td>1979</td><td>monuron</td><td>5</td><td>Ureas</td></tr><tr><td>1954</td><td>2003</td><td>TCA</td><td>0</td><td>Chlorocarbonic acids</td></tr><tr><td>1955</td><td>-</td><td>MCPB</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1955</td><td>1961</td><td>potassium cyanate</td><td>0</td><td>Mineral salts</td></tr><tr><td>1956</td><td>2008</td><td>diuron</td><td>5</td><td>Ureas</td></tr><tr><td>1957</td><td>2003</td><td>dalapon</td><td>15</td><td>Chlorocarbonic acids</td></tr><tr><td>1957</td><td>2018</td><td>mecoprop</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1957</td><td>1990</td><td>sodium chlorate</td><td>0</td><td>Chlorocarbonic acids</td></tr><tr><td>1957</td><td>1961</td><td>sodium monochloracetate</td><td>0</td><td>Chlorocarbonic acids</td></tr><tr><td>1957</td><td>2007</td><td>naptalam</td><td>19</td><td>Aryl-carboxylates</td></tr><tr><td>1957</td><td>2003</td><td>simazine</td><td>5</td><td>Triazines</td></tr><tr><td>1958</td><td>1989</td><td>TBA</td><td>4</td><td>Benzoates</td></tr><tr><td>1958</td><td>2016</td><td>amitrole</td><td>34</td><td>Triazolocarboxamide</td></tr><tr><td>1958</td><td>2020</td><td>chlorpropham</td><td>23</td><td>Carbamates</td></tr><tr><td>1958</td><td>1998</td><td>neburon</td><td>5</td><td>Ureas</td></tr><tr><td>1960</td><td>2003</td><td>atrazine</td><td>5</td><td>Triazines</td></tr><tr><td>1960</td><td>1992</td><td>chlorbufam</td><td>23</td><td>Carbamates</td></tr><tr><td>1960</td><td>1992</td><td>cycluron</td><td>5</td><td>Ureas</td></tr><tr><td>1961</td><td>-</td><td>2,4-DB</td><td>4</td><td>Phenoxy-carboxylates</td></tr></tbody></table>

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<table><thead><tr><td>Start</td><td>End</td><td>Active substances</td><td>HRAC</td><td>Chemical family</td></tr></thead><tbody><tr><td>1961</td><td>1990</td><td>di-allate</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1961</td><td>1962</td><td>sodium dichloro butyrate</td><td>0</td><td>Chlorocarbonic acids</td></tr><tr><td>1961</td><td>2019</td><td>diquat</td><td>22</td><td>Pyridiniums</td></tr><tr><td>1961</td><td>1969</td><td>metam</td><td>0</td><td>Carbamate</td></tr><tr><td>1961</td><td>2007</td><td>prometryn</td><td>5</td><td>Triazines</td></tr><tr><td>1962</td><td>1987</td><td>barban</td><td>23</td><td>Carbamates</td></tr><tr><td>1962</td><td>1977</td><td>pentanochlor</td><td>5</td><td>Amides</td></tr><tr><td>1962</td><td>2010</td><td>propanil</td><td>5</td><td>Amides</td></tr><tr><td>1963</td><td>2020</td><td>chloridazon = pyrazon</td><td>5</td><td>Pyridazinone</td></tr><tr><td>1963</td><td>1991</td><td>chloroxuron</td><td>5</td><td>Ureas</td></tr><tr><td>1963</td><td>2010</td><td>dichlobenil</td><td>29</td><td>Nitriles</td></tr><tr><td>1963</td><td>2003</td><td>dichlorprop</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1963</td><td>1987</td><td>di-isopropyl dixanthogen</td><td>0</td><td>Carbamate</td></tr><tr><td>1963</td><td>2002</td><td>EPTC</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1963</td><td>2018</td><td>linuron</td><td>5</td><td>Ureas</td></tr><tr><td>1963</td><td>2007</td><td>paraquat</td><td>22</td><td>Pyridiniums</td></tr><tr><td>1963</td><td>1964</td><td>propham</td><td>23</td><td>Carbamates</td></tr><tr><td>1963</td><td>-</td><td>tri-allate</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1964</td><td>1969</td><td>chloramben</td><td>4</td><td>Benzoates</td></tr><tr><td>1964</td><td>1980</td><td>sulfallate</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1965</td><td>1996</td><td>diphenamid</td><td>15</td><td>Acetamides</td></tr><tr><td>1965</td><td>2016</td><td>ioxynil</td><td>6</td><td>Nitriles</td></tr><tr><td>1965</td><td>2009</td><td>molinate</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1965</td><td>2000</td><td>monalide</td><td>15</td><td>Anilides</td></tr><tr><td>1965</td><td>2002</td><td>monolinuron</td><td>5</td><td>Ureas</td></tr><tr><td>1965</td><td>-</td><td>picloram</td><td>4</td><td>Pyridyloxy-carboxylates</td></tr><tr><td>1966</td><td>1973</td><td>phenyl-carbonate</td><td>0</td><td>Non-classified</td></tr><tr><td>1966</td><td>1998</td><td>desmetryn</td><td>5</td><td>Triazines</td></tr><tr><td>1966</td><td>1985</td><td>fenoprop</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1966</td><td>-</td><td>lenacil</td><td>5</td><td>Uracils</td></tr><tr><td>1966</td><td>-</td><td>metobromuron</td><td>5</td><td>Ureas</td></tr><tr><td>1966</td><td>1973</td><td>methoprotryne</td><td>5</td><td>Triazines</td></tr><tr><td>1966</td><td>2008</td><td>trifluralin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1967</td><td>-</td><td>carbetamide</td><td>23</td><td>Carbamates</td></tr><tr><td>1967</td><td>1997</td><td>dinoterb</td><td>24</td><td>Dinitrophenols</td></tr><tr><td>1968</td><td>1969</td><td>fluometuron</td><td>5</td><td>Ureas</td></tr><tr><td>1969</td><td>2007</td><td>bromacil</td><td>5</td><td>Uracils</td></tr><tr><td>1969</td><td>2003</td><td>chlorthiamid</td><td>29</td><td>Nitriles</td></tr><tr><td>1969</td><td>-</td><td>dicamba</td><td>4</td><td>Benzoates</td></tr><tr><td>1969</td><td>2009</td><td>methabenzthiazuron</td><td>5</td><td>Ureas</td></tr><tr><td>1969</td><td>2007</td><td>metoxuron</td><td>5</td><td>Ureas</td></tr><tr><td>1969</td><td>1987</td><td>nitrofen</td><td>14</td><td>Diphenyl ethers</td></tr></tbody></table>

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<table><thead><tr><td>Start</td><td>End</td><td>Active substances</td><td>HRAC</td><td>Chemical family</td></tr></thead><tbody><tr><td>1969</td><td>-</td><td>phenmedipham</td><td>5</td><td>Phenylcarbamates</td></tr><tr><td>1969</td><td>2010</td><td>propachlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>1969</td><td>2003</td><td>terbutryn</td><td>5</td><td>Triazines</td></tr><tr><td>1970</td><td>2008</td><td>alachlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>1970</td><td>2003</td><td>ametryn</td><td>5</td><td>Triazines</td></tr><tr><td>1970</td><td>2011</td><td>chlorthal-dimethyl = DCPA</td><td>3</td><td>Benzoates</td></tr><tr><td>1970</td><td>-</td><td>chlorotoluron</td><td>5</td><td>Ureas</td></tr><tr><td>1970</td><td>2002</td><td>cyanazine</td><td>5</td><td>Triazines</td></tr><tr><td>1970</td><td>2003</td><td>cycloate</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1970</td><td>1971</td><td>dichlormate</td><td>34</td><td>Carbamates</td></tr><tr><td>1970</td><td>1973</td><td>phenobenzuron</td><td>5</td><td>Ureas</td></tr><tr><td>1970</td><td>-</td><td>propyzamide</td><td>3</td><td>Benzamides</td></tr><tr><td>1972</td><td>2012</td><td>asulam</td><td>18</td><td>Carbamates</td></tr><tr><td>1972</td><td>-</td><td>bentazon</td><td>6</td><td>Benzothiadiazinone</td></tr><tr><td>1972</td><td>1984</td><td>benzoylprop-ethyl</td><td>23</td><td>Arylaminopropionic acid</td></tr><tr><td>1972</td><td>-</td><td>bromoxynil</td><td>6</td><td>Nitriles</td></tr><tr><td>1972</td><td>1975</td><td>brompyrazon</td><td>5</td><td>Pyridazinone</td></tr><tr><td>1972</td><td>1975</td><td>isonuron</td><td>5</td><td>Ureas</td></tr><tr><td>1972</td><td>-</td><td>metribuzin</td><td>5</td><td>Triazinones</td></tr><tr><td>1972</td><td>-</td><td>napropamide</td><td>15</td><td>Acetamides</td></tr><tr><td>1972</td><td>1987</td><td>nitralin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1972</td><td>2015</td><td>oxadiazon</td><td>14</td><td>N-Phenyl-oxadiazolones</td></tr><tr><td>1972</td><td>2007</td><td>terbacil</td><td>5</td><td>Uracils</td></tr><tr><td>1972</td><td>1998</td><td>terbumeton</td><td>5</td><td>Triazines</td></tr><tr><td>1972</td><td>-</td><td>terbuthylazine</td><td>5</td><td>Triazines</td></tr><tr><td>1973</td><td>1988</td><td>butylate</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1973</td><td>1991</td><td>secbumeton</td><td>5</td><td>Triazines</td></tr><tr><td>1974</td><td>-</td><td>benefin=benfluralin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1974</td><td>1996</td><td>difenzoquat</td><td>0</td><td>Pyrazolium</td></tr><tr><td>1974</td><td>1978</td><td>flamprop</td><td>0</td><td>Arylaminopropionic acid</td></tr><tr><td>1974</td><td>2017</td><td>isoproturon</td><td>5</td><td>Ureas</td></tr><tr><td>1975</td><td>1981</td><td>benazolin-ethyl</td><td>4</td><td>Benzothiazolone</td></tr><tr><td>1975</td><td>-</td><td>ethofumesate</td><td>15</td><td>Benzofuran</td></tr><tr><td>1975</td><td>-</td><td>glyphosate</td><td>9</td><td>Glycine</td></tr><tr><td>1975</td><td>2003</td><td>metolachlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>1975</td><td>1979</td><td>penoxalin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1976</td><td>1980</td><td>tiocarbazyl</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1977</td><td>2009</td><td>butralin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1977</td><td>1978</td><td>cyanatryn</td><td>5</td><td>Triazines</td></tr><tr><td>1977</td><td>-</td><td>metamitron</td><td>5</td><td>Triazinones</td></tr><tr><td>1978</td><td>-</td><td>clopyralid</td><td>4</td><td>Pyridyloxy-carboxylates</td></tr><tr><td>1978</td><td>-</td><td>diclofop-methyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr></tbody></table>

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<table><thead><tr><td>Start</td><td>End</td><td>Active substances</td><td>HRAC</td><td>Chemical family</td></tr></thead><tbody><tr><td>1978</td><td>2002</td><td>dimefuron</td><td>5</td><td>Ureas</td></tr><tr><td>1978</td><td>1991</td><td>ethylfluralin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1978</td><td>2003</td><td>flamprop-M-isopropyl</td><td>0</td><td>Arylaminopropionic acid</td></tr><tr><td>1978</td><td>1983</td><td>tebuthiuron</td><td>5</td><td>Ureas</td></tr><tr><td>1979</td><td>1993</td><td>alloxydim</td><td>1</td><td>Cyclohexanediones</td></tr><tr><td>1979</td><td>-</td><td>dimethachlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>1979</td><td>2003</td><td>siduron</td><td>5</td><td>Ureas</td></tr><tr><td>1980</td><td>1989</td><td>bromofenoxim</td><td>6</td><td>Nitriles</td></tr><tr><td>1980</td><td>2007</td><td>hexazinone</td><td>5</td><td>Triazinones</td></tr><tr><td>1980</td><td>-</td><td>pendimethalin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1980</td><td>2000</td><td>tebutam</td><td>3</td><td>Benzamides</td></tr><tr><td>1980</td><td>1995</td><td>vernolate</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1982</td><td>2002</td><td>fosamine-ammonium</td><td>0</td><td>Organophosphate</td></tr><tr><td>1982</td><td>-</td><td>oxyfluorfen</td><td>14</td><td>Diphenyl ethers</td></tr><tr><td>1982</td><td>-</td><td>pyridate</td><td>6</td><td>Phenyl-pyridazines</td></tr><tr><td>1982</td><td>-</td><td>triclopyr</td><td>4</td><td>Pyridyloxy-carboxylates</td></tr><tr><td>1983</td><td>-</td><td>bifenox</td><td>14</td><td>Diphenyl ethers</td></tr><tr><td>1983</td><td>-</td><td>metazachlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>1984</td><td>1995</td><td>chlomethoxyfen</td><td>14</td><td>Diphenyl ethers</td></tr><tr><td>1984</td><td>2015</td><td>chlorsulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1984</td><td>1985</td><td>fluazifop</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1984</td><td>-</td><td>oryzalin</td><td>3</td><td>Dinitroanilines</td></tr><tr><td>1984</td><td>2003</td><td>sethoxydim</td><td>1</td><td>Cyclohexanediones</td></tr><tr><td>1985</td><td>-</td><td>flurochloridone</td><td>12</td><td>N-Phenyl heterocycles</td></tr><tr><td>1985</td><td>2004</td><td>quizalofop</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1986</td><td>-</td><td>fluazifop-P-butyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1986</td><td>2018</td><td>glufosinate-ammonium</td><td>10</td><td>Phosphinic acids</td></tr><tr><td>1986</td><td>2007</td><td>imazamethabenz-methyl</td><td>2</td><td>Imidazolinones</td></tr><tr><td>1986</td><td>-</td><td>isoxaben</td><td>29</td><td>Benzamides</td></tr><tr><td>1986</td><td>-</td><td>metsulfuron-methyl</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1987</td><td>-</td><td>fluroxypyr</td><td>4</td><td>Pyridyloxy-carboxylates</td></tr><tr><td>1987</td><td>1992</td><td>haloxyfop-etotyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1987</td><td>-</td><td>mecoprop-P</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1987</td><td>-</td><td>thifensulfuron-methyl</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1988</td><td>-</td><td>aclonifen</td><td>32</td><td>Diphenyl ethers</td></tr><tr><td>1988</td><td>-</td><td>dichlorprop-P</td><td>4</td><td>Phenoxy-carboxylates</td></tr><tr><td>1988</td><td>-</td><td>diflufenican</td><td>12</td><td>Phenyl ethers</td></tr><tr><td>1988</td><td>2003</td><td>norflurazon</td><td>12</td><td>Pyridazinone</td></tr><tr><td>1988</td><td>1995</td><td>tralkoxydim</td><td>1</td><td>Cyclohexanediones</td></tr><tr><td>1989</td><td>2020</td><td>desmedipham</td><td>5</td><td>Phenylcarbamates</td></tr><tr><td>1989</td><td>1992</td><td>fenoxaprop</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1989</td><td>2002</td><td>triasulfuron</td><td>2</td><td>Sulfonylureas</td></tr></tbody></table>

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<table><thead><tr><td>Start</td><td>End</td><td>Active substances</td><td>HRAC</td><td>Chemical family</td></tr></thead><tbody><tr><td>1990</td><td>-</td><td>cycloxydim</td><td>1</td><td>Cyclohexanediones</td></tr><tr><td>1990</td><td>-</td><td>fenoxaprop-P-ethyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1990</td><td>1992</td><td>flamprop-M</td><td>0</td><td>Arylaminopropionic acid</td></tr><tr><td>1990</td><td>2007</td><td>pretilachlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>1990</td><td>-</td><td>propaquizafop</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1990</td><td>-</td><td>prosulfocarb</td><td>15</td><td>Thiocarbamates</td></tr><tr><td>1990</td><td>-</td><td>quizalofop-P-ethyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1991</td><td>2003</td><td>acifluorfen-sodium</td><td>14</td><td>Diphenyl ethers</td></tr><tr><td>1991</td><td>-</td><td>amidosulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1991</td><td>-</td><td>bensulfuron-methyl</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1991</td><td>-</td><td>clomazone</td><td>13</td><td>isoxazolidinones</td></tr><tr><td>1991</td><td>2002</td><td>fluoroglycofen-ethyl</td><td>34</td><td>Diphenyl ethers</td></tr><tr><td>1991</td><td>2007</td><td>fomesafen</td><td>14</td><td>Diphenyl ethers</td></tr><tr><td>1991</td><td>2004</td><td>quinclorac</td><td>4</td><td>Quinoline-carboxylates</td></tr><tr><td>1991</td><td>-</td><td>tribenuron-methyl</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1993</td><td>2008</td><td>haloxyfop-methyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1993</td><td>-</td><td>nicosulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1993</td><td>-</td><td>rimsulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1994</td><td>2003</td><td>cinosulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1994</td><td>-</td><td>clodinafop-propargyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>1994</td><td>2008</td><td>dimethenamid</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>1994</td><td>1997</td><td>flupoxam</td><td>29</td><td>Triazolocarboxamide</td></tr><tr><td>1994</td><td>-</td><td>quinmerac</td><td>4</td><td>Quinoline-carboxylates</td></tr><tr><td>1994</td><td>-</td><td>sulcotrione</td><td>27</td><td>Triketones</td></tr><tr><td>1994</td><td>-</td><td>triflusulfuron-methyl</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1995</td><td>2015</td><td>metosulam</td><td>2</td><td>Triazolopyrimidine</td></tr><tr><td>1997</td><td>-</td><td>clethodim</td><td>1</td><td>Cyclohexanediones</td></tr><tr><td>1998</td><td>2020</td><td>flurtamone</td><td>12</td><td>Pyridazinone</td></tr><tr><td>1999</td><td>-</td><td>azimsulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1999</td><td>-</td><td>carfentrazone-ethyl</td><td>14</td><td>Triazolinones</td></tr><tr><td>1999</td><td>-</td><td>flumioxazin</td><td>14</td><td>N-Phenyl-imides</td></tr><tr><td>1999</td><td>2018</td><td>flupyrtsulfuron-methyl-sodium</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>1999</td><td>-</td><td>isoxaflutole</td><td>27</td><td>Isoxazoles</td></tr><tr><td>1999</td><td>-</td><td>prosulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2000</td><td>2013</td><td>acetochlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>2000</td><td>-</td><td>flazasulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2001</td><td>2013</td><td>cinidon-ethyl</td><td>14</td><td>N-Phenyl-imides</td></tr><tr><td>2001</td><td>-</td><td>flufenacet</td><td>15</td><td>α-Oxyacetamides</td></tr><tr><td>2001</td><td>-</td><td>sulfosulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2002</td><td>-</td><td>cyhalofop-butyl</td><td>1</td><td>Aryloxyphenoxy-propionates</td></tr><tr><td>2002</td><td>-</td><td>florasulam</td><td>2</td><td>Triazolopyrimidine</td></tr><tr><td>2002</td><td>-</td><td>imazamox</td><td>2</td><td>Imidazolinones</td></tr></tbody></table>

Continue
Continuation

<table><thead><tr><td>Start</td><td>End</td><td>Active substances</td><td>HRAC</td><td>Chemical family</td></tr></thead><tbody><tr><td>2002</td><td>-</td><td>iodosulfuron-methyl-sodium</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2002</td><td>-</td><td>mesotrione</td><td>27</td><td>Triketones</td></tr><tr><td>2002</td><td>-</td><td>pyraflufen-ethyl</td><td>14</td><td>Phenylpyrazoles</td></tr><tr><td>2003</td><td>-</td><td>dimethnamid-P</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>2003</td><td>-</td><td>mesosulfuron-methyl</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2003</td><td>-</td><td>picolinafen</td><td>12</td><td>Phenyl ethers</td></tr><tr><td>2003</td><td>-</td><td>S-metolachlor</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>2004</td><td>-</td><td>foramsulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2004</td><td>2015</td><td>oxadiargyl</td><td>14</td><td>N-Phenyl-oxadiazolones</td></tr><tr><td>2004</td><td>-</td><td>propoxycarbazone-sodium</td><td>2</td><td>Triazolinones</td></tr><tr><td>2010</td><td>-</td><td>beflubutamid</td><td>12</td><td>Phenyl ethers</td></tr><tr><td>2010</td><td>-</td><td>penoxsulam</td><td>2</td><td>Triazolopyrimidine</td></tr><tr><td>2010</td><td>-</td><td>pyroxsulam</td><td>2</td><td>Triazolopyrimidine</td></tr><tr><td>2010</td><td>-</td><td>tembotrione</td><td>27</td><td>Triketones</td></tr><tr><td>2011</td><td>-</td><td>acetic acid</td><td>0</td><td>Non-classified</td></tr><tr><td>2011</td><td>-</td><td>pethoxamid</td><td>15</td><td>α-Chloroacetamides</td></tr><tr><td>2011</td><td>-</td><td>tritosulfuron</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2012</td><td>-</td><td>pelargonic acid</td><td>0</td><td>Non-classified</td></tr><tr><td>2012</td><td>-</td><td>aminopyralid</td><td>4</td><td>Pyridyloxy-carboxylates</td></tr><tr><td>2012</td><td>-</td><td>pinoxaden</td><td>1</td><td>Phenylpyrazoline</td></tr><tr><td>2013</td><td>-</td><td>thiencarbazone-methyl</td><td>2</td><td>Triazolinones</td></tr><tr><td>2017</td><td>-</td><td>halosulfuron-methyl</td><td>2</td><td>Sulfonylureas</td></tr><tr><td>2018</td><td>-</td><td>halauxifen-methyl</td><td>4</td><td>Pyridine-carboxylates</td></tr><tr><td>2020</td><td>-</td><td>caprylic acid</td><td>0</td><td>Non-classified</td></tr></tbody></table>