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Some effects of environmental warfare on agriculture in Indochina
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SOME E F F E C T S OF E N V I R O N M E N T A L W A R F A R E ON A G R I C U L T U R E IN INDOCHINA According to a recent report from Vietnam (Agence France Presse, November 9th, 1975) the new government "has begun a campaign to restore and extend the country's war-mangled forests." What is the magnitude of the damage to Vietnam's forests and to other agricultural resources after more than ten years of war? Although it will take many more studies to fully d o c u m e n t the extent of damage, preliminary investigations made during the second Indochina war have provided some information. It is the purpose of this paper to summarize what is known a b o u t war damage to agriculture in Indochina. The information has been gathered by the U.S. National Academy of Sciences (NAS), the American Association for the Advancement of Sciences (AAAS), and several individual scientists, including the author, during field trips to Indochina from 1969 to 1973. In order to fully understand the problem it is essential to know something a b o u t the weapons systems and techniques that were the most destructive to the environment. These were United States systems -- either employed by the armed forces of the U.S. or its allies. The principal so-called conventional weapons were high explosive fragmentation bombs dropped from aircraft, and artillery shells. Also employed were a large number of unconventional, non-nuclear weapons and techniques never before used in warfare; tested and developed in Indochina. These were herbicides, R o m e plows, high concussion non-fragmentation 7.5-ton-concussion bombs, fuel air explosive weapons, and weather modification. An age-old technique in war was also employed: induction of massive forest and prairie fires. Let us first consider the conventional weapons and their effects. In the years from 1965 to 1973, Indochina, a region slightly larger than the state of Texas, was b o m b a r d e d by a tonnage of munitions amounting to twice the total used by the U.S. in all the theaters of World War II. This equals a b o u t 16 million tons of munitions exploded in Indochina; half from the air and half from weapons on the ground. A b o u t 71% of this bombing and shelling t o o k place in Vietnam south of the 17th parallel. It is important to point o u t here that only a b o u t 8% of U.S. bombing missions in Indochina were directed at tactical military targets, or, in other words, in direct support of troops. The remaining 92% were described as strategic bombing missions (harassing, interdiction, or area denial attacks). In World War II strategic bombing targets had been factories, port cities, railroads, etc. However, in the Indochina War strategic targets were most often the land and forests (Figs 1 and 2), because they gave cover, food, and sanctuary to the forces arrayed against the U.S. and its
272
Fig.1. Manioc fields near Saigon cratered by 500-pound bombs from B-52 aircraft. (Photo by G.H. Orians)
Fig.2. A Mangrove forest with permanently water-filled craters caused by B-52 bombing.
273 allies. These missions were carried out by B-52 aircraft flying at an altitude of approximately 30 000 feet. A typical B-52 mission, made up of five planes, delivered 540 500-pound bombs in a pattern that saturated an area about a half mile wide and 3 miles long -- almost 1 000 acres. Throughout the war, an average of nine missions per day were flown and therefore more than 100 000 new bomb craters were created each month. All told, from 1965 to 1973 about 21 million bomb craters, covering perhaps 500 000 acres, were created. On the basis of ground and air observations I assume a typical crater formed by a 500-pound bomb to be 26 feet in diameter and 13 feet deep. Each of these bombs spread shrapnel fragments over an area of about threequarters of an acre. The explosions spread metal fragments over a total of 33 million acres, if we disregard overlap. In the crop lands of the Mekong Delta, the bombs penetrated the water table resulting in craters permanently filled with water. It is very difficult to fill these pools since most of the soil is impacted around the crater rather than being thrown up. These water-filled craters would appear to be excellent habitat for mosquito larvae and, in fact, during the war there was a tremendous increase in both malaria and hemorrhagic fever -- both mosquito borne diseases. In crop lands hit by heavy bombardment there are numbers of unexploded munitions. According to the Department of Defense, about 1--2% of bombs and artillery shells failed to explode on impact. Many Indochinese farmers have been killed by detonating such munitions when they have attempted to reclaim bombed lands. Furthermore, the metal fragments from the bomb casings buried in the soil cut the hoofs of water buffalo used as draft animals, sometimes resulting in infection and death of the animals. Many thousands of these animals were killed by B-52 attacks and there is now a grave shortage in many areas. In the summer of 1973 I observed at first hand the effects of a B-52 bombing attack upon village agriculture (Cam Chinh) in northern Quang Tri Province. Several hundred people lived in this village and, as is typical in the areas administered by the Provisional Revolutionary Government, each family had a private garden plot of some 100--200 m 2 . There were many craters in the village. Assuming that one typical B-52 bomb crater has a diameter of 8 m, then the cratered area of an individual family's garden plot, struck by a bomb, approaches 33% of its private arable land. It was interesting in this village to note that the villagers had planted bananas (Musa sapientum) and manioc (Manihot esculenta) in the walls of the craters (Fig.3). They lacked the equipm e n t necessary to fill in the numerous large holes. Near the city of Dong Hoi in the southern panhandle of the Democratic Republic of Vietnam we observed some huge craters in agricultural land (Fig.4). They were about 100 feet across, possibly 60 feet deep, and partially water-filled, making it impossible to measure the depth. Upon m y return to the U.S. I was informed by Department of Defense officials that these craters were made by 2 000 pound laser-guided " s m a r t " bombs. I was unable to
274
Fig.3. Freshly planted bananas and manioc growing in a crater in the village of Cam Chinh, Quang Tri Province.
determine what the targets of these bombs had been in the areas I observed. The bombing with 500, 750, and 2 000 pound bombs had disrupted rice (Oryza sativa) growing in Indochina by breaching m a n y of the complicated irrigation systems. I observed a bomb-cratered dike (Fig.5} near Dong Hoi in the Democratic Republic of Vietnam. At high tide, sea water flowed across the craters, flooding once fertile rice lands. We were told it would take about three years to desalt the soil for rice culture. We also visited a high dam across a river in Quang Nam province. The dam produced a reservoir with over 15 km 2 of surface water 10 m deep. Work was underway to repair serious damage done to the dam by repeated bombing attacks. Craters were numerous at each end of the dam. The i m p o u n d m e n t had been used to irrigate 2 500 ha of rice fields during the dry season and to prevent floods during the wet monsoons. In hilly terrain the tearing up of the soil by bombs produces erosion. Furthermore, there is in some localities the possibility of lat~rization of cratered regions as a result of the removal of vegetation and humus by the explosions. In addition to using conventional fragmentation bombs against forests, the U.S. Air Force developed and made operational the 7.5 ton BLU/82B high concussion bomb. This was designed to blast openings in dense forest to create "instant helicopter landing zones". Its effects are produced entirely by concussion and create a virtually perfect clearing about 100 yards in diameter.
275
Fig.4. Part of the wall of a crater made by a 2 000-pound laser-guided bomb. Several such huge craters were observed in fields near Dong Hoi, D.R.V. I t was first u s e d in V i e t n a m in 1 9 7 0 , a n d several h u n d r e d w e r e d r o p p e d during t h e r e m a i n i n g y e a r s o f t h e war. I t was last used in May, 1 9 7 5 o n K o h T a n g island against t h e C a m b o d i a n s . A n o t h e r bizarre, u n c o n v e n t i o n a l device used t o clear f o r e s t s a n d d e t o n a t e land m i n e s was t h e CBU-55 Fuel Air E x p l o s i v e ( F A E ) . An a e r o s o l fuel-air c l o u d ( e t h y l e n e o x i d e a n d air) is dispersed over a wide area a n d t h e n d e t o n a t ed c r e a t i n g a v e r y high o v e r p r e s s u r e . T h e e x p l o s i o n also c o n s u m e s all o x y g e n in t h e i m m e d i a t e vicinity, a n d r e p o r t e d l y , m a n y p e o p l e were killed b y a n o x i a f r o m this w e a p o n d u r i n g t h e b a t t l e f o r Saigon in the spring of 1975. According to t h e U.S. D e p a r t m e n t o f D e f e n s e a b o u t 2 0 0 0 o f these w e a p o n s were dropped during the period 1972--1975.
276
Fig.5. Dike near Dong Hoi, D.R.V. damaged by 2 000-pound laser-guided bomb.
Fig.6. Dead mangrove forest killed by herbicides. (Photo by A.H. Westing)
277 The effects of this bombardment upon the timber industry in Indochina, especially Vietnam south of the 17th parallel, have been very severe. Individual trees have been destroyed in the explosions. Those nearby have been riddled by shrapnel and many have subsequently died as a result of infection by fungi, which produces necrotic areas -- this weakens the trees, which are then blown down. The craters make it very difficult to use heavy equipment to remove the logs from the forests, which in any case are often valueless because of the shrapnel. Mill owners refuse to buy or pay adequate prices for logs thus damaged because of the threat to their saws. Rubber trees seem to be particularly susceptible to fungal rot after having been subjected to bombardment. One official informed me that he had lost 80% of his trees within 2 years after a bombing attack upon his plantation. The U.S. National Academy of Sciences' study, which concerned itself mainly with herbicides, commented: "Damage to inland forests by bombing was also heavy in both extent (area) and intensity (destruction of all trees large and small in the area of the crater ... heavy damage in its perimeter including metal fragments imbedded in surviving trees which pose a hazard in sawmills etc. and may reduce the value of timber from South Vietnam in general)." Let us now consider the effects of the non-explosive, unconventional weapons and techniques developed and made operational by the U.S. in Indochina. Probably the most damaging to agriculture was the application of herbicides by multi-engined aircraft. In order to defoliate brush and trees to increase visibility and to kill crops approximately 120 million pounds of assorted herbicides were sprayed over more then 4 million acres of South Vietnam (about 10 percent of its total area). In eastern Cambodia almost 200 000 acres of prime agricultural land, principally rubber plantations, food crops, and fruit trees, were sprayed in a clandestine raid, presumably by Air America aircraft, which occurred in April--May of 1969. The most c o m m o n l y used chemicals were 2,4-D and 2,4,5-T (Agent Orange), 2,4-D and picloram (Agent White) and cacodylic acid (Agent Blue). In 1969 I observed at first hand the effects of defoliation on the mangrove forests south of Saigon. The mangrove trees (Rhizophoraceae) are used for charcoal production, and the forests are the breeding areas for large numbers of valuable food animals from crustacea to bony fish. I traveled some 65 miles through the sprayed mangrove forests and almost the whole area was completely barren. Although mangrove forests are communities of several different species they are uniformly sensitive to herbicides and one spray kills essentially all the trees exposed to the herbicide. I was unable to observe any regeneration of mangrove trees or other types of vegetation (Fig.6). The American Association for the Advancement of Science study stated that between one-third and one-half of the mangrove forests of Vietnam south of the 17th parallel were destroyed. It was deeply impressed by the total destruction of all such vegetation by a single spraying and by no evidence of forest regeneration. Large numbers of crabs were present and may be a fac~
278 tor in preventing regrowth of mangroves by eating the seedlings. The AAAS recommended intensive reforestation so that mangroves can again stabilize the shoreline and prevent the current erosion. With respect to upland forests, the AAAS study estimated that almost 4 million acres (about one-fifth of the mature forests of south Vietnam) had been sprayed. Where spraying was single or multiple it appeared to have destroyed most of the larger trees. This resulted in sunlight reaching deeper into the forest with resulting invasion of bamboo (Bambusa species) and grasses, especially Irnperata. Thus the mature open forest floor has been replaced by dense underbrush. The study estimated that the a m o u n t of timber killed by herbicides in Vietnam would have supplied all the domestic needs of that country for the next 30 years. The U.S. National Academy of Sciences' study of the effects of the herbicide program has confirmed the above observations in all its essentials. In addition to the native mangrove and inland forests, Indochina has many large and small rubber plantations. In 1969 I talked with the director of the Rubber Research Institute of Vietnam and saw some of the effects of defoliation on rubber production in that country and in Cambodia. In Vietnam in 1960, rubber plantations yielded 2 345 tons of dry rubber per acre. In 1967 the yield dropped to 1 745 tons per acre. This was in distinct contrast to the yield in Malaysia which showed an increase during these years. The Rubber Research Institute felt that the decrease in yield resulted from a combination of decreased tapping forced by military activity, less competent labor, and herbicide damage. Although herbicide attacks on most rubber plantations were officially prohibited, there was a very serious problem due to the drift of herbicides from target forests, often at some distance from the affected rubber plantations. In 1969 I observed the effects on rubber plantations, both large and small, in eastern Cambodia. About 38 300 acres were affected in clandestine U.S. herbicide attacks. Sixty-five percent of the trees in this area were heavily damaged. From May to November 1969 latex production of the sprayed rubber trees was reduced by an average of 45%, with a loss to the producers of about 11 million dollars. It is important to note here that most of the plantations have recovered and I have recently been informed by officials of the Royal Cambodian Government that rubber production is once again in progress in this area. What were the effects of herbicides on food plants? I noted very severe damage to jackfruit (Artocarpus heterophyllus) trees, a most important source of fruit for Indochinese people, and to mango (Mangitera indica) manioc, and guava (Fig.7). In Cambodia about 45 000 jackfruit trees had been killed or severely damaged in the clandestine herbicide attack in 1969. The Cambodian government estimated that about 1.2 million dollars damage to crops other than rubber had resulted from this attack. The AAAS made a detailed study in one area of central Vietnam in which mountain rice crops
279
had been repeatedly attacked with Agent Blue (cacodylic acid). This is an arsenical compound, although the arsenic is in a relatively nontoxic valency state. (The U.S. Forest Service in an order dated April 23rd, 1974 lifted a total ban on the domestic use of cacodylic acid and permitted its use in the U.S. only under very rigid restrictions.) A total of a b o u t 530 000 acres of crop land, mainly rice, was sprayed with Agent Blue, destroying enough rice to have fed an estimated 600 000 people for a year. Moreover, perhaps half as much again was destroyed by Agents Orange and White. The N.A.S. reports that between 200 to 300 pounds of the highly toxic dioxin contaminant of Agent Orange were released in Vietnam. The AAAS study found residues of dioxin in fishes caught in local rivers or purchased in Saigon markets in 1970 and 1973. It was because of the contamination by
Fig.7. Dead j a c k f r u i t trees near a village in Q u a n g Tri Province. T h e y h a d b e e n killed b y drift of h e r b i c i d e s d u r i n g a n a t t a c k b y U.S. a i r c r a f t o n a n e a r b y target forest.
280 dioxin of Agent Orange t hat the U.S. G o v e r n m e n t ordered a ban on herbicide operations in 1970. Following this ban the U.S. Army greatly accelerated the use of bulldozers with special blades made near Rome, Georgia. These specially arm ored and equipped vehicles are know n as Rome plows and were designed to replace herbicides as destroyers of forests and vegetative cover. A b o u t 2% of the total land surface of Vietnam was scraped bare (Fig.8). South Vietnamese forest officials estimated that about 20 million board feet o f marketable h a r d w o o d had been des t royed by the plows -- at a loss to the Saigon G o v e r n m e n t of approximately 15 million dollars. Many rubber trees were also d e s t r o y e d by this technique because t hey were removed from the borders of the highways passing through plantations. Some 2 500 acres of rubber plantations were so destroyed. According to French rubber interests this a m o u n t e d to a loss of 26 million dollars to these French owners, who had received no compensation as of 1971. An o th er tech nol ogy that was used by the U.S. in its arsenal of environmental warfare was the seeding of clouds to produce rainfall over Indochina. In March o f 1974 the U.S. Defense D e p a r t m e n t described to the U.S. Senate the 21.6 million dollar program of seeding clouds with silver or lead iodide. Between 1967 and 1972, 2 602 sorties were flown. The purpose according to
Fig. 8. A formerly forested area northwest of Saigon that had been defoliated, bombed, and bull-dozed with Rome plows.
281 the U.S. Defense D e p a r t m e n t was t o "increase rainfall sufficiently to f u r t h e r s o f t e n r o a d surfaces, cause landslides along r o a d w a y s , and t o wash o u t river crossings." What e f f e c t this m a y have had o n agriculture o f the regions so a f f e c t e d has n o t y e t been d e t e r m i n e d . B e t w e e n 1 9 6 5 and 1 9 6 8 the U.S. a t t e m p t e d t o initiate f o r e s t fires in selected f o r e s t regions o f S o u t h V i e t n a m with the assistance o f p e r s o n n e l o f the U.S. F o r e s t Service's F o r e s t Fire L a b o r a t o r y in M o n t a n a . T h e forests were first s p r a y e d with herbicides, t h e n b o m b e d with i n c e n d i a r y agents. These a t t e m p t s were c o n s i d e r e d militarily unsuccessful b u t u n d o u b t a b l y had considerable i m p a c t o n f o r e s t p r o d u c t i v i t y . Much o f the a b o v e i n f o r m a t i o n was p r e s e n t e d b y Le Chi T h a n h , the Vietn a m e s e ecologist f r o m the Provisional R e v o l u t i o n a r y G o v e r n m e n t and m y s e l f to the First World Congress o f E c o l o g y , held at T h e Hague, T h e N e t h e r l a n d s , in S e p t e m b e r o f 1974. As a result, the Congress and the I n t e r n a t i o n a l Association for E c o l o g y ( I N T E C O L ) passed the following resolution: " W H E R E A S , t h e r e is great danger to certain e c o s y s t e m s o f intense physical, chemical, or biological agents are applied f o r p u r p o s e s o f warfare; and whereas, such p r o c e d u r e s m a y p e r m a n e n t l y alter the a f f e c t e d e c o s y s t e m such t h a t it b e c o m e s no longer able to s u p p o r t h u m a n life or r e t u r n to its previous state; now, t h e r e f o r e , be it resolved by I N T E C O L : t h a t ecologists s h o u l d be e n c o u r a g e d t o seek to p r o m o t e a g r e e m e n t a m o n g g o v e r n m e n t s to p r o h i b i t : (1) a n y research or e x p e r i m e n t a t i o n relating to t h e d e v e l o p m e n t or testing o f a n y such activity as a w e a p o n o f war; and (2) p r o h i b i t the use o f a n y such e n v i r o n m e n t a l - m o d i f i c a t i o n - a c t i v i t y as a w e a p o n o f w a r . " H o p e f u l l y , ecologists, agriculturists, and e n v i r o n m e n t a l i s t s t h r o u g h o u t the w o r l d will take steps to i m p l e m e n t this resolution.
E.W. PFEIFFER
(Missoula, Mont., UoS.A.) REFERENCES Boffey, P.N., 1971. Herbicides in Vietnam ; AAAS study finds widespread devastation. Science, 171: 43--47. Lang, A., Chairman, National Research Council Committee on the effects of herbicides in Vietnam, 1974. The effects of herbicides in South Vietnam; Part A -- Summary and Conclusions. National Academy of Sciences, Washington, D.C., 1: 8--12. Orians, G.H. and Pfeiffer, E.W., 1970. Ecological effects of the war in Vietnam. Science, 168: 544--554. Shapley, D., 1974. Weather warfare: Pentagon concedes 7-year Vietnam effort. Science, 184: 1059--1061. Westing, A.H., 1972. Herbicidal damage to Cambodia. In: A. Vennema, A.H. Westing, J.B. Neilands, G.H. Orians and E.W. Pfeiffer. Harvest of Death, Chemical Warfare in Vietnam and Cambodia. The Free Press, New York, N.Y., 304 pp. Westing, A.H. and Pfeiffer, E.W., 1972. The cratering of Indochina. Scientific American, 226: 2--11.
SOME E F F E C T S OF E N V I R O N M E N T A L W A R F A R E ON A G R I C U L T U R E IN INDOCHINA According to a recent report from Vietnam (Agence France Presse, November 9th, 1975) the new government "has begun a campaign to restore and extend the country's war-mangled forests." What is the magnitude of the damage to Vietnam's forests and to other agricultural resources after more than ten years of war? Although it will take many more studies to fully d o c u m e n t the extent of damage, preliminary investigations made during the second Indochina war have provided some information. It is the purpose of this paper to summarize what is known a b o u t war damage to agriculture in Indochina. The information has been gathered by the U.S. National Academy of Sciences (NAS), the American Association for the Advancement of Sciences (AAAS), and several individual scientists, including the author, during field trips to Indochina from 1969 to 1973. In order to fully understand the problem it is essential to know something a b o u t the weapons systems and techniques that were the most destructive to the environment. These were United States systems -- either employed by the armed forces of the U.S. or its allies. The principal so-called conventional weapons were high explosive fragmentation bombs dropped from aircraft, and artillery shells. Also employed were a large number of unconventional, non-nuclear weapons and techniques never before used in warfare; tested and developed in Indochina. These were herbicides, R o m e plows, high concussion non-fragmentation 7.5-ton-concussion bombs, fuel air explosive weapons, and weather modification. An age-old technique in war was also employed: induction of massive forest and prairie fires. Let us first consider the conventional weapons and their effects. In the years from 1965 to 1973, Indochina, a region slightly larger than the state of Texas, was b o m b a r d e d by a tonnage of munitions amounting to twice the total used by the U.S. in all the theaters of World War II. This equals a b o u t 16 million tons of munitions exploded in Indochina; half from the air and half from weapons on the ground. A b o u t 71% of this bombing and shelling t o o k place in Vietnam south of the 17th parallel. It is important to point o u t here that only a b o u t 8% of U.S. bombing missions in Indochina were directed at tactical military targets, or, in other words, in direct support of troops. The remaining 92% were described as strategic bombing missions (harassing, interdiction, or area denial attacks). In World War II strategic bombing targets had been factories, port cities, railroads, etc. However, in the Indochina War strategic targets were most often the land and forests (Figs 1 and 2), because they gave cover, food, and sanctuary to the forces arrayed against the U.S. and its
272
Fig.1. Manioc fields near Saigon cratered by 500-pound bombs from B-52 aircraft. (Photo by G.H. Orians)
Fig.2. A Mangrove forest with permanently water-filled craters caused by B-52 bombing.
273 allies. These missions were carried out by B-52 aircraft flying at an altitude of approximately 30 000 feet. A typical B-52 mission, made up of five planes, delivered 540 500-pound bombs in a pattern that saturated an area about a half mile wide and 3 miles long -- almost 1 000 acres. Throughout the war, an average of nine missions per day were flown and therefore more than 100 000 new bomb craters were created each month. All told, from 1965 to 1973 about 21 million bomb craters, covering perhaps 500 000 acres, were created. On the basis of ground and air observations I assume a typical crater formed by a 500-pound bomb to be 26 feet in diameter and 13 feet deep. Each of these bombs spread shrapnel fragments over an area of about threequarters of an acre. The explosions spread metal fragments over a total of 33 million acres, if we disregard overlap. In the crop lands of the Mekong Delta, the bombs penetrated the water table resulting in craters permanently filled with water. It is very difficult to fill these pools since most of the soil is impacted around the crater rather than being thrown up. These water-filled craters would appear to be excellent habitat for mosquito larvae and, in fact, during the war there was a tremendous increase in both malaria and hemorrhagic fever -- both mosquito borne diseases. In crop lands hit by heavy bombardment there are numbers of unexploded munitions. According to the Department of Defense, about 1--2% of bombs and artillery shells failed to explode on impact. Many Indochinese farmers have been killed by detonating such munitions when they have attempted to reclaim bombed lands. Furthermore, the metal fragments from the bomb casings buried in the soil cut the hoofs of water buffalo used as draft animals, sometimes resulting in infection and death of the animals. Many thousands of these animals were killed by B-52 attacks and there is now a grave shortage in many areas. In the summer of 1973 I observed at first hand the effects of a B-52 bombing attack upon village agriculture (Cam Chinh) in northern Quang Tri Province. Several hundred people lived in this village and, as is typical in the areas administered by the Provisional Revolutionary Government, each family had a private garden plot of some 100--200 m 2 . There were many craters in the village. Assuming that one typical B-52 bomb crater has a diameter of 8 m, then the cratered area of an individual family's garden plot, struck by a bomb, approaches 33% of its private arable land. It was interesting in this village to note that the villagers had planted bananas (Musa sapientum) and manioc (Manihot esculenta) in the walls of the craters (Fig.3). They lacked the equipm e n t necessary to fill in the numerous large holes. Near the city of Dong Hoi in the southern panhandle of the Democratic Republic of Vietnam we observed some huge craters in agricultural land (Fig.4). They were about 100 feet across, possibly 60 feet deep, and partially water-filled, making it impossible to measure the depth. Upon m y return to the U.S. I was informed by Department of Defense officials that these craters were made by 2 000 pound laser-guided " s m a r t " bombs. I was unable to
274
Fig.3. Freshly planted bananas and manioc growing in a crater in the village of Cam Chinh, Quang Tri Province.
determine what the targets of these bombs had been in the areas I observed. The bombing with 500, 750, and 2 000 pound bombs had disrupted rice (Oryza sativa) growing in Indochina by breaching m a n y of the complicated irrigation systems. I observed a bomb-cratered dike (Fig.5} near Dong Hoi in the Democratic Republic of Vietnam. At high tide, sea water flowed across the craters, flooding once fertile rice lands. We were told it would take about three years to desalt the soil for rice culture. We also visited a high dam across a river in Quang Nam province. The dam produced a reservoir with over 15 km 2 of surface water 10 m deep. Work was underway to repair serious damage done to the dam by repeated bombing attacks. Craters were numerous at each end of the dam. The i m p o u n d m e n t had been used to irrigate 2 500 ha of rice fields during the dry season and to prevent floods during the wet monsoons. In hilly terrain the tearing up of the soil by bombs produces erosion. Furthermore, there is in some localities the possibility of lat~rization of cratered regions as a result of the removal of vegetation and humus by the explosions. In addition to using conventional fragmentation bombs against forests, the U.S. Air Force developed and made operational the 7.5 ton BLU/82B high concussion bomb. This was designed to blast openings in dense forest to create "instant helicopter landing zones". Its effects are produced entirely by concussion and create a virtually perfect clearing about 100 yards in diameter.
275
Fig.4. Part of the wall of a crater made by a 2 000-pound laser-guided bomb. Several such huge craters were observed in fields near Dong Hoi, D.R.V. I t was first u s e d in V i e t n a m in 1 9 7 0 , a n d several h u n d r e d w e r e d r o p p e d during t h e r e m a i n i n g y e a r s o f t h e war. I t was last used in May, 1 9 7 5 o n K o h T a n g island against t h e C a m b o d i a n s . A n o t h e r bizarre, u n c o n v e n t i o n a l device used t o clear f o r e s t s a n d d e t o n a t e land m i n e s was t h e CBU-55 Fuel Air E x p l o s i v e ( F A E ) . An a e r o s o l fuel-air c l o u d ( e t h y l e n e o x i d e a n d air) is dispersed over a wide area a n d t h e n d e t o n a t ed c r e a t i n g a v e r y high o v e r p r e s s u r e . T h e e x p l o s i o n also c o n s u m e s all o x y g e n in t h e i m m e d i a t e vicinity, a n d r e p o r t e d l y , m a n y p e o p l e were killed b y a n o x i a f r o m this w e a p o n d u r i n g t h e b a t t l e f o r Saigon in the spring of 1975. According to t h e U.S. D e p a r t m e n t o f D e f e n s e a b o u t 2 0 0 0 o f these w e a p o n s were dropped during the period 1972--1975.
276
Fig.5. Dike near Dong Hoi, D.R.V. damaged by 2 000-pound laser-guided bomb.
Fig.6. Dead mangrove forest killed by herbicides. (Photo by A.H. Westing)
277 The effects of this bombardment upon the timber industry in Indochina, especially Vietnam south of the 17th parallel, have been very severe. Individual trees have been destroyed in the explosions. Those nearby have been riddled by shrapnel and many have subsequently died as a result of infection by fungi, which produces necrotic areas -- this weakens the trees, which are then blown down. The craters make it very difficult to use heavy equipment to remove the logs from the forests, which in any case are often valueless because of the shrapnel. Mill owners refuse to buy or pay adequate prices for logs thus damaged because of the threat to their saws. Rubber trees seem to be particularly susceptible to fungal rot after having been subjected to bombardment. One official informed me that he had lost 80% of his trees within 2 years after a bombing attack upon his plantation. The U.S. National Academy of Sciences' study, which concerned itself mainly with herbicides, commented: "Damage to inland forests by bombing was also heavy in both extent (area) and intensity (destruction of all trees large and small in the area of the crater ... heavy damage in its perimeter including metal fragments imbedded in surviving trees which pose a hazard in sawmills etc. and may reduce the value of timber from South Vietnam in general)." Let us now consider the effects of the non-explosive, unconventional weapons and techniques developed and made operational by the U.S. in Indochina. Probably the most damaging to agriculture was the application of herbicides by multi-engined aircraft. In order to defoliate brush and trees to increase visibility and to kill crops approximately 120 million pounds of assorted herbicides were sprayed over more then 4 million acres of South Vietnam (about 10 percent of its total area). In eastern Cambodia almost 200 000 acres of prime agricultural land, principally rubber plantations, food crops, and fruit trees, were sprayed in a clandestine raid, presumably by Air America aircraft, which occurred in April--May of 1969. The most c o m m o n l y used chemicals were 2,4-D and 2,4,5-T (Agent Orange), 2,4-D and picloram (Agent White) and cacodylic acid (Agent Blue). In 1969 I observed at first hand the effects of defoliation on the mangrove forests south of Saigon. The mangrove trees (Rhizophoraceae) are used for charcoal production, and the forests are the breeding areas for large numbers of valuable food animals from crustacea to bony fish. I traveled some 65 miles through the sprayed mangrove forests and almost the whole area was completely barren. Although mangrove forests are communities of several different species they are uniformly sensitive to herbicides and one spray kills essentially all the trees exposed to the herbicide. I was unable to observe any regeneration of mangrove trees or other types of vegetation (Fig.6). The American Association for the Advancement of Science study stated that between one-third and one-half of the mangrove forests of Vietnam south of the 17th parallel were destroyed. It was deeply impressed by the total destruction of all such vegetation by a single spraying and by no evidence of forest regeneration. Large numbers of crabs were present and may be a fac~
278 tor in preventing regrowth of mangroves by eating the seedlings. The AAAS recommended intensive reforestation so that mangroves can again stabilize the shoreline and prevent the current erosion. With respect to upland forests, the AAAS study estimated that almost 4 million acres (about one-fifth of the mature forests of south Vietnam) had been sprayed. Where spraying was single or multiple it appeared to have destroyed most of the larger trees. This resulted in sunlight reaching deeper into the forest with resulting invasion of bamboo (Bambusa species) and grasses, especially Irnperata. Thus the mature open forest floor has been replaced by dense underbrush. The study estimated that the a m o u n t of timber killed by herbicides in Vietnam would have supplied all the domestic needs of that country for the next 30 years. The U.S. National Academy of Sciences' study of the effects of the herbicide program has confirmed the above observations in all its essentials. In addition to the native mangrove and inland forests, Indochina has many large and small rubber plantations. In 1969 I talked with the director of the Rubber Research Institute of Vietnam and saw some of the effects of defoliation on rubber production in that country and in Cambodia. In Vietnam in 1960, rubber plantations yielded 2 345 tons of dry rubber per acre. In 1967 the yield dropped to 1 745 tons per acre. This was in distinct contrast to the yield in Malaysia which showed an increase during these years. The Rubber Research Institute felt that the decrease in yield resulted from a combination of decreased tapping forced by military activity, less competent labor, and herbicide damage. Although herbicide attacks on most rubber plantations were officially prohibited, there was a very serious problem due to the drift of herbicides from target forests, often at some distance from the affected rubber plantations. In 1969 I observed the effects on rubber plantations, both large and small, in eastern Cambodia. About 38 300 acres were affected in clandestine U.S. herbicide attacks. Sixty-five percent of the trees in this area were heavily damaged. From May to November 1969 latex production of the sprayed rubber trees was reduced by an average of 45%, with a loss to the producers of about 11 million dollars. It is important to note here that most of the plantations have recovered and I have recently been informed by officials of the Royal Cambodian Government that rubber production is once again in progress in this area. What were the effects of herbicides on food plants? I noted very severe damage to jackfruit (Artocarpus heterophyllus) trees, a most important source of fruit for Indochinese people, and to mango (Mangitera indica) manioc, and guava (Fig.7). In Cambodia about 45 000 jackfruit trees had been killed or severely damaged in the clandestine herbicide attack in 1969. The Cambodian government estimated that about 1.2 million dollars damage to crops other than rubber had resulted from this attack. The AAAS made a detailed study in one area of central Vietnam in which mountain rice crops
279
had been repeatedly attacked with Agent Blue (cacodylic acid). This is an arsenical compound, although the arsenic is in a relatively nontoxic valency state. (The U.S. Forest Service in an order dated April 23rd, 1974 lifted a total ban on the domestic use of cacodylic acid and permitted its use in the U.S. only under very rigid restrictions.) A total of a b o u t 530 000 acres of crop land, mainly rice, was sprayed with Agent Blue, destroying enough rice to have fed an estimated 600 000 people for a year. Moreover, perhaps half as much again was destroyed by Agents Orange and White. The N.A.S. reports that between 200 to 300 pounds of the highly toxic dioxin contaminant of Agent Orange were released in Vietnam. The AAAS study found residues of dioxin in fishes caught in local rivers or purchased in Saigon markets in 1970 and 1973. It was because of the contamination by
Fig.7. Dead j a c k f r u i t trees near a village in Q u a n g Tri Province. T h e y h a d b e e n killed b y drift of h e r b i c i d e s d u r i n g a n a t t a c k b y U.S. a i r c r a f t o n a n e a r b y target forest.
280 dioxin of Agent Orange t hat the U.S. G o v e r n m e n t ordered a ban on herbicide operations in 1970. Following this ban the U.S. Army greatly accelerated the use of bulldozers with special blades made near Rome, Georgia. These specially arm ored and equipped vehicles are know n as Rome plows and were designed to replace herbicides as destroyers of forests and vegetative cover. A b o u t 2% of the total land surface of Vietnam was scraped bare (Fig.8). South Vietnamese forest officials estimated that about 20 million board feet o f marketable h a r d w o o d had been des t royed by the plows -- at a loss to the Saigon G o v e r n m e n t of approximately 15 million dollars. Many rubber trees were also d e s t r o y e d by this technique because t hey were removed from the borders of the highways passing through plantations. Some 2 500 acres of rubber plantations were so destroyed. According to French rubber interests this a m o u n t e d to a loss of 26 million dollars to these French owners, who had received no compensation as of 1971. An o th er tech nol ogy that was used by the U.S. in its arsenal of environmental warfare was the seeding of clouds to produce rainfall over Indochina. In March o f 1974 the U.S. Defense D e p a r t m e n t described to the U.S. Senate the 21.6 million dollar program of seeding clouds with silver or lead iodide. Between 1967 and 1972, 2 602 sorties were flown. The purpose according to
Fig. 8. A formerly forested area northwest of Saigon that had been defoliated, bombed, and bull-dozed with Rome plows.
281 the U.S. Defense D e p a r t m e n t was t o "increase rainfall sufficiently to f u r t h e r s o f t e n r o a d surfaces, cause landslides along r o a d w a y s , and t o wash o u t river crossings." What e f f e c t this m a y have had o n agriculture o f the regions so a f f e c t e d has n o t y e t been d e t e r m i n e d . B e t w e e n 1 9 6 5 and 1 9 6 8 the U.S. a t t e m p t e d t o initiate f o r e s t fires in selected f o r e s t regions o f S o u t h V i e t n a m with the assistance o f p e r s o n n e l o f the U.S. F o r e s t Service's F o r e s t Fire L a b o r a t o r y in M o n t a n a . T h e forests were first s p r a y e d with herbicides, t h e n b o m b e d with i n c e n d i a r y agents. These a t t e m p t s were c o n s i d e r e d militarily unsuccessful b u t u n d o u b t a b l y had considerable i m p a c t o n f o r e s t p r o d u c t i v i t y . Much o f the a b o v e i n f o r m a t i o n was p r e s e n t e d b y Le Chi T h a n h , the Vietn a m e s e ecologist f r o m the Provisional R e v o l u t i o n a r y G o v e r n m e n t and m y s e l f to the First World Congress o f E c o l o g y , held at T h e Hague, T h e N e t h e r l a n d s , in S e p t e m b e r o f 1974. As a result, the Congress and the I n t e r n a t i o n a l Association for E c o l o g y ( I N T E C O L ) passed the following resolution: " W H E R E A S , t h e r e is great danger to certain e c o s y s t e m s o f intense physical, chemical, or biological agents are applied f o r p u r p o s e s o f warfare; and whereas, such p r o c e d u r e s m a y p e r m a n e n t l y alter the a f f e c t e d e c o s y s t e m such t h a t it b e c o m e s no longer able to s u p p o r t h u m a n life or r e t u r n to its previous state; now, t h e r e f o r e , be it resolved by I N T E C O L : t h a t ecologists s h o u l d be e n c o u r a g e d t o seek to p r o m o t e a g r e e m e n t a m o n g g o v e r n m e n t s to p r o h i b i t : (1) a n y research or e x p e r i m e n t a t i o n relating to t h e d e v e l o p m e n t or testing o f a n y such activity as a w e a p o n o f war; and (2) p r o h i b i t the use o f a n y such e n v i r o n m e n t a l - m o d i f i c a t i o n - a c t i v i t y as a w e a p o n o f w a r . " H o p e f u l l y , ecologists, agriculturists, and e n v i r o n m e n t a l i s t s t h r o u g h o u t the w o r l d will take steps to i m p l e m e n t this resolution.
E.W. PFEIFFER
(Missoula, Mont., UoS.A.) REFERENCES Boffey, P.N., 1971. Herbicides in Vietnam ; AAAS study finds widespread devastation. Science, 171: 43--47. Lang, A., Chairman, National Research Council Committee on the effects of herbicides in Vietnam, 1974. The effects of herbicides in South Vietnam; Part A -- Summary and Conclusions. National Academy of Sciences, Washington, D.C., 1: 8--12. Orians, G.H. and Pfeiffer, E.W., 1970. Ecological effects of the war in Vietnam. Science, 168: 544--554. Shapley, D., 1974. Weather warfare: Pentagon concedes 7-year Vietnam effort. Science, 184: 1059--1061. Westing, A.H., 1972. Herbicidal damage to Cambodia. In: A. Vennema, A.H. Westing, J.B. Neilands, G.H. Orians and E.W. Pfeiffer. Harvest of Death, Chemical Warfare in Vietnam and Cambodia. The Free Press, New York, N.Y., 304 pp. Westing, A.H. and Pfeiffer, E.W., 1972. The cratering of Indochina. Scientific American, 226: 2--11.