Operation Ranch Hand
Encyclopedia
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
, lasting from 1962 until 1971. It was part of the overall herbicidal warfare
Herbicidal warfare
Herbicidal warfare is a form of Chemical warfare in which the objective is to destroy the plant-based ecosystem of an area. In contrast to other forms, its use is not prohibited by international agreement...
program during the war called "Operation Trail Dust". Ranch Hand involved spraying an estimated 20 million USgals (75,708.2 m³) of defoliant
Defoliant
A defoliant is any chemical sprayed or dusted on plants to cause its leaves to fall off. A classic example of a highly toxic defoliant is Agent Orange, which the United States armed forces used abundantly to defoliate regions of Vietnam during the Vietnam War from 1961 to 1970.Defoliants differ...
s and herbicide
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...
s over rural areas of South Vietnam
South Vietnam
South Vietnam was a state which governed southern Vietnam until 1975. It received international recognition in 1950 as the "State of Vietnam" and later as the "Republic of Vietnam" . Its capital was Saigon...
in an attempt to deprive the Viet Cong of vegetation cover and food, in possible violation of the Geneva Conventions
Geneva Conventions
The Geneva Conventions comprise four treaties, and three additional protocols, that establish the standards of international law for the humanitarian treatment of the victims of war...
. Areas of Laos and Cambodia were also sprayed to a lesser extent. Nearly 20,000 sorties were flown between 1961 and 1971.
The "Ranch Handers" motto was "Only we can prevent forests" a take on the popular US Forestry poster of Smokey the Bear. During the ten years of spraying over 5 million acres (20,234.3 km²) of forest and 500000 acres (2,023.4 km²) of crops were heavily damaged or destroyed. Around 20% of the forest of South Vietnam were sprayed at least once.
The herbicides were sprayed by the US Air Force flying C-123s using the call sign "Hades". The planes were fitted with specially developed spray tanks with a capacity of 1000 gallons (3.8 m³) of herbicides. A plane sprayed a swath of land that was 80 meters wide and 16 km (~10 miles) long in about 4½ minutes at a rate of about 3 USgal/acre. Sorties usually consisted of 3 – 5 planes flying side by side. 95% of the herbicides and defoliants used in the war were sprayed by the US Air Force as part of Operation Ranch Hand. The remaining 5% were sprayed by the US Chemical Corps and other military branches as well as the RVN
RVN
RVN can stand for:* South Vietnam* CBN , which had this callsign* Ruud van Nistelrooy, a Dutch footballer* Rovaniemi Airport, in Finland...
by hand sprayers, spray trucks, helicopters and boats primarily around US military installations.
Herbicides
The herbicides used were sprayed up to 50 times the concentration that would have been use in normal agricultural use. The most common herbicide used was Herbicide Orange, more commonly referred to as Agent OrangeAgent Orange
Agent Orange is the code name for one of the herbicides and defoliants used by the U.S. military as part of its herbicidal warfare program, Operation Ranch Hand, during the Vietnam War from 1961 to 1971. Vietnam estimates 400,000 people were killed or maimed, and 500,000 children born with birth...
, a fifty-fifty mixture of two herbicides 2,4-D (2,4-dichlorophenoxyacetic acid) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid). The other most common color coded herbicides used were Agent Blue
Agent Blue
Agent Blue is one of the "rainbow herbicides" that is known for its use by the United States during the Vietnam War. It was sprayed on rice paddies and other crops in an attempt to deprive the Viet Cong of valuable crops. Agent Blue is a mixture of two arsenic-containing compounds, sodium...
(cacodylic acid
Cacodylic acid
Cacodylic acid is the chemical compound with the formula 2AsO2H. Derivatives of cacodylic acid, cacodylates, were frequently used as herbicides. For example, "Agent Blue," one of the chemicals used during the Vietnam War, is a mixture of cacodylic acid and sodium cacodylate...
) that was primarily used against food crops and Agent White
Agent White
Agent White is the code name for a powerful herbicide and defoliant used by the U.S. military in its Herbicidal warfare program during the Vietnam War. The name comes from the white stripe painted on the barrels to identify the contents...
(picloram
Picloram
Picloram is a systemic herbicide used for general woody plant control, sold under the trade names Tordon and Grazon. It also controls a wide range of broad-leaved weeds, but most grasses are resistant...
) often used when Agent Orange was not available.
The Agents used, known as the rainbow herbicides
Rainbow Herbicides
The Rainbow Herbicides are a group of chemicals used by the United States military in Southeast Asia during the Vietnam War. Success with Project AGILE field tests with herbicides in South Vietnam in 1961 led to the formal herbicidal program Trail Dust...
, their active ingredients and years used were as follow:
- Agent PinkAgent PinkAgent Pink is the code name for a powerful herbicide and defoliant used by the U.S. military in its Herbicidal Warfare program during the Vietnam War. The name comes from the pink stripe painted on the barrels to identify the contents. It was one of the so-called "rainbow herbicides" that included...
(60% – 40% n-butylButylIn organic chemistry, butyl is a four-carbon alkyl radical or substituent group with general chemical formula -C4H9, derived from either of the two isomers of butane....
:isobutyl esterEsterEsters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...
s of 2,4,5-T) used in 1961, 1965 - Agent GreenAgent GreenAgent Green is the code name for a powerful herbicide and defoliant used by the U.S. military in its Herbicidal Warfare program during the Vietnam War. The name comes from the green stripe painted on the barrels to identify the contents. It was one of the so-called "rainbow herbicides" that...
(n-butyl ester of 2,4,5-T) unclear when used but believed to be at the same time as Pink - Agent PurpleAgent PurpleAgent Purple is the code name for a powerful herbicide and defoliant used by the U.S. military and the Canadian Government in their Herbicidal Warfare program during the Vietnam War. The name comes from the purple stripe painted on the barrels to identify the contents...
(50% n-butyl ester of 2,4-D, 30% n-butyl ester 2,4,5-T, 20% isobutyl ester of 2,4,5-T) used from 1962–1965 - Agent BlueAgent BlueAgent Blue is one of the "rainbow herbicides" that is known for its use by the United States during the Vietnam War. It was sprayed on rice paddies and other crops in an attempt to deprive the Viet Cong of valuable crops. Agent Blue is a mixture of two arsenic-containing compounds, sodium...
(cacodylic acidCacodylic acidCacodylic acid is the chemical compound with the formula 2AsO2H. Derivatives of cacodylic acid, cacodylates, were frequently used as herbicides. For example, "Agent Blue," one of the chemicals used during the Vietnam War, is a mixture of cacodylic acid and sodium cacodylate...
and sodium cacodylate) used from 1962 – 1971 (in powder and water solution) - Agent WhiteAgent WhiteAgent White is the code name for a powerful herbicide and defoliant used by the U.S. military in its Herbicidal warfare program during the Vietnam War. The name comes from the white stripe painted on the barrels to identify the contents...
(acid weight basis:21.2% tri-isopropanolamine salts of 2,4-D and 5.7% picloram) used from 1966–1971 - Agent OrangeAgent OrangeAgent Orange is the code name for one of the herbicides and defoliants used by the U.S. military as part of its herbicidal warfare program, Operation Ranch Hand, during the Vietnam War from 1961 to 1971. Vietnam estimates 400,000 people were killed or maimed, and 500,000 children born with birth...
(50% n-butyl ester of 2,4-D and 50% n-butyl ester of 2,4,5-T) used from 1965–1970
The herbicides were procured by the US military from Dow Chemical Company
Dow Chemical Company
The Dow Chemical Company is a multinational corporation headquartered in Midland, Michigan, United States. As of 2007, it is the second largest chemical manufacturer in the world by revenue and as of February 2009, the third-largest chemical company in the world by market capitalization .Dow...
(all but Blue), Monsanto Company (Orange, Purple and Pink), Hercules Inc.
Hercules Inc.
Hercules, Inc., was a chemical and munitions manufacturing company based in Wilmington, Delaware, which was formed in 1912 as the Hercules Powder Company. Hercules was spun-off from the DuPont Corporation as a result of U.S. federal government actions in the field of antitrusts...
(Orange and Purple), Thompson-Hayward Chemical Company (Orange and Pink), Diamond Alkali
Diamond Alkali
Diamond Alkali Company was an American chemical company incorporated in 1910 in West Virginia by a group of glass industry businessmen from Pittsburgh. The company soon established a large chemical plant at Fairport Harbor, Ohio, which would operate for over sixty years. In 1948, the headquarters...
/Shamrock Company (Orange, Blue, Purple and Pink), US Rubber Company (Orange), Thompson Chemicals Corporation (Orange and Pink), Agrisect Company (Orange and Purple), Hoffman-Taft Inc (Orange), and the Ansul
Ansul
Ansul Fire School is a fire school which was founded in 1940 and is located in Marinette, Wisconsin, United States. It trains students with classroom and field instruction, with emphasis on hands-on firefighting....
Chemical Company (Blue).
65% of the herbicides used contained 2,4,5-Trichlorophenoxyacetic acid
2,4,5-Trichlorophenoxyacetic acid
2,4,5-Trichlorophenoxyacetic acid , a synthetic auxin, is a chlorophenoxy acetic acid herbicide used to defoliate broad-leafed plants. It was developed in the late 1940s and was widely used in the agricultural industry until being phased out, starting in the late 1970s due to toxicity concerns....
that was found to have been contaminated with 2,3,7,8-Tetrachlorodibenzodioxin
2,3,7,8-Tetrachlorodibenzodioxin
2,3,7,8-Tetrachlorodibenzo-p-dioxin is a polychlorinated dibenzo-p-dioxin . It is the most potent compound of the series and became known as a contaminant in Agent Orange, a herbicide used in the Vietnam War, as well as the Seveso disaster...
a known human carcinogen. About 12 million USgals (45,424.9 m³) of dioxin contaminated herbicides were sprayed over Southeast Asia during American combat operations.
In 2005, the New Zealand government confirmed that Agent Orange chemicals had been supplied from New Zealand to the United States military during the conflict. From 1962 to 1987, 2,4,5T herbicide had been manufactured at an Ivon Watkins-Dow plant in New Plymouth
New Plymouth
New Plymouth is the major city of the Taranaki Region on the west coast of the North Island of New Zealand. It is named after Plymouth, Devon, England, from where the first English settlers migrated....
, which was then shipped to U.S. military bases in South East Asia.
Operations
For most of the war 'Operation Ranch Hand' was based out of the Bien Hoa Air Base (1966–1970) for operations in the Mekong DeltaMekong Delta
The Mekong Delta is the region in southwestern Vietnam where the Mekong River approaches and empties into the sea through a network of distributaries. The Mekong delta region encompasses a large portion of southwestern Vietnam of . The size of the area covered by water depends on the season.The...
region where the U.S. Navy patrol boat
Patrol boat
A patrol boat is a relatively small naval vessel generally designed for coastal defense duties.There have been many designs for patrol boats. They may be operated by a nation's navy, coast guard, or police force, and may be intended for marine and/or estuarine or river environments...
s were vulnerable to attack from the undergrowth at the water's edge. The storage, mixing, loading, washing and parking ramp was just off the inside taxiway between the Hot Cargo Ramp and the Control Tower. For operations along the central coast and the Ho Chi Minh Trail
Ho Chi Minh trail
The Ho Chi Minh trail was a logistical system that ran from the Democratic Republic of Vietnam to the Republic of Vietnam through the neighboring kingdoms of Laos and Cambodia...
regions Ranch Hand operated out of the Da Nang Air Base (1964–71). Other bases of operation included Phu Cat AB (1968–1970), Ton San Nhut AB (1962–66), Nha Trang AB (1968–69) Phan Rang AB (1970–72), and Tuy Hoa AB (1971–72). Other bases were also used as temporary staging areas for Ranch Hand. The Da Nang, Bien Hoa and Phu Cat Air bases are still heavily contaminated with dioxin from the herbicides and have been placed a priority list for containment and clean-up by the Vietnamese government.
The first aerial spraying of herbicides was a test run conducted on 10 August 1961 in a village north of Dak To against foliage. Testing continued over the next year and even though there was doubt in the State Department, the Pentagon and the White House to the efficacy of the herbicides "Operation Ranch Hand" began in early 1962. Individual spray runs had to be approved by President John F. Kennedy
John F. Kennedy
John Fitzgerald "Jack" Kennedy , often referred to by his initials JFK, was the 35th President of the United States, serving from 1961 until his assassination in 1963....
until November 1962 when Kennedy gave the authority to approve most spray runs to the Military Assistance Command, Vietnam and the US Ambassador to South Viet Nam. Ranch Hand was given final approval to spray targets in eastern Laos in December 1965.
The issue of whether or not to allow crop destruction was under great debate due to its potential of violating the Geneva Convention. The president of South Vietnam, Ngo Dinh Diem
Ngo Dinh Diem
Ngô Đình Diệm was the first president of South Vietnam . In the wake of the French withdrawal from Indochina as a result of the 1954 Geneva Accords, Diệm led the effort to create the Republic of Vietnam. Accruing considerable U.S. support due to his staunch anti-Communism, he achieved victory in a...
began to push the US Military Advisory Group in Vietnam and the White House to begin crop destruction in September 1961 but it was not until October 1962 when the White House gave approval for limited testing of Agent Blue against crops in an area believed to be controlled by the Viet Cong. Soon after crop destruction became an integral part of the Ranch Hand program.
The targets for the spray runs were carefully selected to satisfy the strategic and psychological operations goals of the US and South Vietnamese military. The runs were surveyed to pinpoint the target area and then placed on a priority list. Due to the low altitude required for spraying, (ideally 150 feet (45.7 m) above ground), the C-123s were escorted by fighter planes that would strafe or bomb the target area in order to draw out any ground fire if the area was believed to be 'hot'. Runs were planned to enable as straight a run as possible to limit the amount of time the planes were at low altitude. Data on the spray runs, their targets, the herbicide used and amount used, the weather and other details were kept and later put into a data base called the HERBICIDE REPORTING SYSTEM or HERBS tapes.
The effectiveness of the spraying was influenced by many factors including weather and terrain. Spray runs occurred during the early morning hours before temperatures rose above 85 degrees and the winds picked up. Mangroves in the Delta region required only one spraying and did not survive once defoliated. Whereas dense forests in the uplands required two or more spray runs. Within two to three weeks of spraying the leaves would drop from the trees which would remain bare until the next rainy season. In order to defoliate the lower stories of forest cover one or more follow-up spray runs were needed. About 10 percent of the trees sprayed died from a single spray run. Multiple spraying resulted in increased mortality for the trees as did following the herbicide missions with napalm or bombing strikes.
The End of the Operation
The use of herbicides in the Vietnam War was controversial from the beginning, particularly for crop destruction. The scientific community began to protest the use of herbicides in Vietnam as early as 1964 when the Federation of American Scientists objected to the use of defoliants. The American Association for the Advancement of ScienceAmerican Association for the Advancement of Science
The American Association for the Advancement of Science is an international non-profit organization with the stated goals of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsibility, and supporting scientific education and science outreach for the...
(AAAS) issued a resolution in 1966 calling for a field investigation of the herbicide program in Vietnam. In 1967 seventeen Nobel Laureates and 5000 other scientists signed a petition asking for the immediate end to the use of herbicides in Vietnam. Press coverage of the controversial use of herbicides in Vietnam increased in the late 1960s.
In 1970 AAAS sent a team of scientists to conduct field tests of the ecological impacts of the herbicide program in Vietnam. In 1969 a report authored by K. Diane Courtney and others found that 2,4,5-T could cause birth defects and still births in mice. This, and follow-up studies, led the US government to restrict the use of 2,4,5-T in the US in April 1970. The Department of Defense followed suit in Vietnam by 'temporarily' suspending the use of Agent Orange in Vietnam, though they continued to rely on Agent White for defoliation until supplies ran out and the last defoliation run took place on 9 May 1970. Sporadic crop destruction sorties using Agent Blue continued throughout 1970 until the final Ranch Hand run was flown on 7 January 1971.
External links
- An extensive repository of Agent Orange documentation, especially as regards US Military operations and resultant law suits.
- Spraying of Agent orange by US Army in Vietnam and its consequences, Stop USA
- Epandage de l’Agent Orange par l’US Army au Viêt Nam et ses conséquences,
- Agent Orange and Other Herbicides in Vietnam research by Jeanne Stellman
- War Legacies Project collection of Agent Orange research and resources