HISTORY OF THE USE OF OPUNTIA AS FORAGE IN MEXICO

Marco Antonio ANAYA-PÉREZ

INTRODUCTION

Opuntia, often called prickly pear, or cactus pear as it is now usually known in commerce, is a plant typical of the Mexican landscape, and a major symbol of identity for the Mexican people. Together with maize and agave, opuntia has been a staple food, instrumental in enabling human settlement and cultural development of the Chichimeca groups of the centre and north of the country.

Complementary to its importance as food were inter alia its uses as a beverage, medicine, source of dye, and as an object of magical-religious practices. Tlacuilos [the native historians of Pre-Columbian Mexico, who used pictograms to record events], chroniclers, travellers, historians and scientists have left testimony of this. However, the economic importance of opuntia as forage was not perceived during the Spanish Colonial Period, or even after independence.

The few records on the use of opuntia during the colonial and post-independence eras indicate that it was used as animal feed, especially in the northern arid and semi-arid zones. Its use increased from the early 1600s with the introduction of cattle to semi-arid areas and the consequent depletion of grasslands. This situation forced stockmen to cut opuntia pads and burn off the thorns to feed livestock in their pastures, especially during droughts.

In the second half of the twentieth century, the Government of Mexico and some educational institutions began to recognize the importance of opuntia cultivation, particularly for forage. The Colegio de Posgraduados released improved varieties to participate in a programme aimed at stopping overexploitation of wild populations of opuntia, associated with intensive livestock feeding during droughts or as a regular complement to the diet. Opuntia plantations have been promoted as a foundation of reforestation and recovery programmes for extensive degraded areas, aiming to control desertification. There are few studies on the history of opuntia, with the exception of cochineal. This chapter presents a brief account of the utilization of opuntia as forage in Mexico.

ORIGIN

According to Flannery (1985), between the end of the Pleistocene (ca. 100 000 years B.P.) and the beginning of the fifth millennium AD, the prehistoric indigenous group of the semi-arid basins and valleys of the states of Hidalgo, Mexico, Morelos, Guerrero, Puebla and Oaxaca began cultivating a series of native plants, which later became the basic foodstuffs of the ancient middle-American civilizations. For centuries, these native Americans had lived as nomads, learning inter alia, which plants to gather and consume, how to roast opuntia and agave to make them edible, and how to extract syrup from the pods of the mesquite (Prosopis spp.). The cultivation of beans, squash, huatli (Amaranthus sp.), chilies, tomatillo, avocado, and, as Flannery (1985) suggests, perhaps opuntia, agave and other semitropical fruits began between 7 500 and 5 000 years BC.

Since the arrival of man in Mexico in the desert and semi-desert zones, about 20 000 years ago, opuntias have been important as food sources, as well as for drink and medicine. Long before horticultural management of the opuntia was known, the ancient Mexicans consumed it abundantly from the wild.

Fray Bernardino de Sahagún, in his work Historia General de las Cosas de la Nueva España - written during the first half of the 16^th century - reported that native Americans lived for many years and were “healthy and strong.” Their vitality, according to him, was due to the type of diet, which was not cooked with other things. They ate “prickly pear leaves”, prickly pear fruits, roots, mesquite pods, and yucca flowers which they called czotl, honey and rabbits, hares, deer, snakes and fowl (Sahagún, 1997).

On the use of opuntia “sacred tree” as a beverage to quench thirst, Friar Toribio Motolinia said, “... these Indians whom I refer to, because they are from a land so sterile that at times they lack water, drink the juice of these leaves of nocpal...” The fresh and aromatic opuntia fruit, or tuna, was also used for this purpose; they made nochoctli, or pulque (a fermented drink, generally made from the sap of the century plant. - Translator’s note). The word tuna originated in Haiti and was introduced by the Spaniards during the Conquest.

The De la Cruz-Badiano Codex of 1552 shows how opuntia was used to treat several ailments of the human body. For example, opuntia was used to cure burns: “The burned part of our body is cured with the juice of the nopalli with which it should be rubbed on with honey and egg yolk...” (Velázquez, 1998).

The genus Opuntia spread from Mexico to practically the entire American continent (from Alberta, Canada, to Patagonia, Argentina), and, after the Spanish Conquest, to the rest of the world (Flores and Aguirre, 1979). In 1700, Tournefort named opuntias Opuntia, because of their similarity to a thorny plant that grew in the town of Opus, Greece (Velázquez, 1998). In Mexico, several species of the genus Opuntia of the Cactaceae family are called nopal. All of them are endemic to America, and of the 377 recognized species, 104 are found wild in Mexico, and 60 of these are endemic in Mexico.

There are few studies on the history of opuntia, except in its association with cochineal. Tibón (1993), in his History of the name and of the foundation of Mexico, describes the drawing done by the tlacuilo of Fray Diego Durán, of the foundation of Mexico Tenochtitlán:

“To the left of the hill, a beautiful bird with its wings extended has just alighted on a prickly pear and sings, as its open beak indicates. A large snake with forked tongue rises in the direction of the plant...”

“Thus, the tenochtli, the prickly pear of hard red tunas, was, from the beginning, the tree of human hearts. The serpent that emerges from the bowels of the earth is night; the bird that sings over the prickly pear is at once the same eagle-sun...”

It is of interest that the opuntia where the bird, or eagle, has alighted is known by the scientific name of Opuntia streptacantha, which comes from streptos, “twisted” and acantha, “thorn”. The tuna lapidea, according to Dr Francisco Hernandez is similar to opuntia in its flowers and fruit, but with long, narrow, twisted branches (Granados and Castañeda, 1991).

Although the sources consulted for the Colonial Period do not mention the use of opuntia, as a forage plant, without doubt during the droughts which affected New Spain, the livestock that spread throughout the country had to consume opuntia, as reported in sources from the 19^th and 20^th centuries.

DISTRIBUTION

The geographical distribution of the genus Opuntia in Mexico, according to recent studies, reflects the abundance of opuntia and its natural incidence in associations, focusing on the most important species (Granados and Castañeda, 1991; Flores and Aguirre, 1979):

This distribution indicates that the region of Mal Paso, southwest of the city of Zacatecas, has the greatest diversity of opuntia species. In contrast, chroniclers and historians of the colonial period recounted the abundance of opuntia practically throughout the country. From the chronicles of travellers or scientific works, the present distribution includes Querétaro, Guanajuato, Jalisco, Nayarit and Coahuila in Mexico, and Texas in the United States.

Pedro de Rivera, in his trip to northern New Spain at the beginning of the 18^th century, reported that in the direction of San Juan del Río, Querétaro, he found thick vegetation of mesquite, guizaches (Prosopis sp.), and opuntia. In the direction of Ojuelos, Jalisco, near San Miguel El Grande, he passed through flat land with scrub vegetation of oak, mesquite and opuntia. On the border between the kingdoms of New Galicia and Nayarit, he went through rough mountains with many rocks and thick brush of mesquite, guamuchiles, guizaches and opuntia (Trabulse, 1992a).

Alexander Von Humboldt reported that Villa de Saltillo, province of Coahuila, is located in an arid plain which descends toward Monclova, the Río Grande, and the province of Texas, where instead of the wheat he might find in a European plain, he found only fields covered by opuntias (Humboldt, 1984).

COLONIAL MEXICO

Description of the opuntia plant

The morphology of opuntia awed the Europeans, who had never seen a plant like it, leading them to describe it the best they could. During the colonial period, study and recording of opuntia began with the work of Jose Antonio Alzate on cochineal. The nopalli, or cactus pear, was known by the Spaniards as nopal, and the fruit as tuna, although in the 16^th century this plant was also called higuera de indias (fig of the Indies), higuera de pala (shovel fig), tuned de Castilla, nopal de Castilla, chumbos, tuna chumbera, tuna mansa, and tunal (Rojas and Sanders, 1985).

In 1539, Friar Toribio Motolinia, describing his experiences in Michoacán, reported that in this province the tunales were abundant:

“... they are trees that have leaves the thickness of fingers, some thicker and others less, as long as the foot of a man, and as wide as a hand span...” (Motolinia, 1995).

In the mid-16^th century, Friar Bernardino de Sahagún wrote:

“The tree called tuna has large, thick leaves, and green and thorny; this tree gives flowers on the same leaves [and] some are white, others vermilion, others yellow, and others fleshy; produced in this tree are fruits called tunas [that] are very good to eat [and] come out of the same leaves...” (Trabulse, 1993).

Describing opuntia, Friar Bernardino de Sahagún reported:

“There are trees in this land they call nopalli, which means tunal, or tree with tunas; it is a monstrous tree, the trunk is composed of leaves and the branches are made of these same leaves; the leaves are broad and thick, having juice and are viscous; the same leaves have many thorns... The leaves of this tree are eaten raw and cooked.” (Sahagún, 1997).

The Nahuas - a Pre-Columbian tribe that dominated central Mexico - identified several native species whose scientific names, common names and place where identified are the following:

* Nopalea cochenillifera (L.) Salm-Dyck (syn. Cactus cochenillifera L.; Opuntia cochenillifera (L.) Mill), also called nochez opalli (Nahuatl), nopal de San Gabriel (Oaxaca), tuna mansa (Puerto Rico), tuna nopal (El Salvador). This plant and nopal de Castilla (Opuntia ficus-indica L.) are species used in the production of the cochineal insect (Dactylopious coccus Costa). N. cochenillifera has several varieties; the best known and most used is nopalnocheztli, namely cochineal opuntia, which the Spaniards named nopal de Castilla. Another variety is known as nopal de San Gabriel.

* Opuntia Miller (Cactaceae). The most usual name for the cultivated species of this genus is nopal, and the fruit is commonly called tuna.

* Opuntia amyclaea Tenore (syn. O. ficus-indica f. amyclea (Ten.) Schelle and O. ficus-indica var. amyclea (Ten.) Berger.)

* Opuntia ficus-indica (L.) Mill. (syn. Cactus ficus-indica L.). Also known as nopal de Castilla, tuna de Castilla, nochtli; used in the production of cochineal.

* Opuntia imbricata (Haw.) D.C. (syn. Cereus imbricatus Haw., Opuntia rosea D.C., O. decipiens D.C., O. exuviata D.C., O. arborescens Engelm., O. magna Griffiths, O. spinotecta Griffiths, xoconochtle, joconochtle (Jalisco), xoconochtli, joconostle (Zacatecas), cardenche (Durango, Zacatecas), tasajo (Chihuahua), coyonostle (Nuevo Leon and Coahuila), coyonoxtle, coyonostli (Nuevo Leon), tuna joconoxtla (Jalisco), tuna huell, velas de coyote, entraña (New Mexico)). The xoconochtli is a cactus with cylindrical stems with long thorns and very sour fruit.

* Opuntia megacantha Salm-Dyck (syn. O. castillae Griffiths, O. incarnadilla Griffiths), the nopal de Castilla.

* Opuntia streptacantha Lem. Also called tecolonochtli or tecolonochnopalli; this is the cardon nopal or cardona tuna. The fruit is an intense red, aromatic and refreshing. It has great importance in the semi-arid and desert zones (Rojas, 1990).

Friar Francisco de Ajofrín, who travelled through New Spain in the 18^th century, reported that there were opuntia fruit - tunas - almost year-round. Some were white, others yellow, and some were more fleshy (Trabulse, 1992a). Miguel Venegas indicated in the 18^th century that in California the red tunas are infrequent, and in New Spain they called them tunas taponas (Trabulse, 1992b).

The physician Francisco Hernández, in his monumental work Historia Natural de la Nueva España, found seven distinct types of tunas: iztacnochtli, this opuntia was known to the Spaniards as the higuera de las indias (fig of the Indies) which, according to them, was similar to the fig tree, even when neither the plant nor the fruit had any similarity to a fig tree or a fig (Trabulse, 1992b), coznochtli, tlatonochtli, tlapalnochtli, tzaponchtli, zacanochtli (Rojas and Sanders, 1985), and nopalxochcuezltic (Epiphyllum acker Haw.) (Rojas and Sanders, 1985). The Nahuas classified this last plant in the group of tunas, most certainly because of the similarity of its flowers and fruits to those of the nopal, which belong to the same botanical family. This is a plant with long fleshy, undulating leaves and beautiful red flowers.

Bernardino de Sahagún also made interesting records of opuntia species and the diversity of tunas, very similar to that done by Francisco Hernandez (Sahagún, 1997) and Motolinía (1995).

Propagation

Friar Toribio de Benavente explains how opuntia reproduces:

“... and one leaf of these plants is planted and they proceed leaf after leaf, and leaves also come out of the sides, and they become a tree. The leaves at the foot thicken greatly, and become so strong that they become the foot or trunk of the tree... In this New Spain the tree is called nucpai - nopalli - and the fruit is called nuchtli...” (Motolinía, 1995).

“Wherever a leaf falls from this tree, another similar tree is soon formed; and what is admirable is that, after some time, stuck on the leaves appears a gum called alquitira, for which many conifers are used.” (Cervantes, 1991).

Livestock raising

The livestock brought from the West Indies (Cosio, 1987) by the Spaniards caused a revolution in the economy of New Spain, and immense areas previously unused by agriculture were brought into use. The livestock came from Cuba, Santo Domingo and San Juan, Puerto Rico. Hernán Cortés brought the horses (11 horses and 5 mares), and Gregorio Villalobos brought cattle from Santo Domingo (Cosio, 1987). Livestock gave agriculture a boost, providing animal traction, transport and manure. No less important was its contribution to the development of mining; animals were used as driving power and transport. In addition, livestock was used as a basic source of food. For these reasons and because of the immense virgin grasslands that existed, livestock multiplied and spread from the central high plateau to the rest of New Spain during the 16^th century. Although it decreased, notably in the 17^th century, the numbers were so great that in many regions many wild herds were formed.

The Spanish Mesta concept - a formal organization of livestock producers- also came to New Spain, where it was composed of owners of livestock ranches (Chevalier, 1982). Extensive grazing of sheep and goats began, moving livestock from place to place for summer and winter grazing. The routes crossed New Spain in every direction. The Cabildo (government) of Mexico City founded the first Mesta in New Spain on July 31, 1527. Later, Puebla (1541), Oaxaca (1543) and Michoacán (1563) followed (Chevalier, 1982).

Contemporary sources indicate the extent of the changes:

* As of 1579, no fewer than 200 000 sheep from Querétaro moved 300 to 400 km during the month of September, to find fresh pastures near Lake Chapala and western Michoacan, returning to their ranches in May.

* The livestock from Tepeaca, Puebla, and some from the Central Plateau, wintered in pastures of Veracruz on the Gulf of Mexico.

* From the Huasteca, livestock went to graze on the shores of Río Verde, in San Luis Potosí.

* In 1648, more than 300 000 sheep from the mountains of New Spain were taken to the extensive plains of the Kingdom of Nuevo Leon, where they grazed for more than six months. In 1685, it is said that 555 000 head of cattle arrived (Chevalier, 1982; Humboldt, 1984).

* At the end of the 16^th century, in the High and Low Mixtec regions, the indigenous people came to own 250 000 head goats and sheep. In Tlaxcala and Puebla, the communities had more than 400 000 head of sheep and goats, and the communities of Zimatlan, Oaxaca and Jilotepec, State of Mexico, together had more than 350 000 head (Rojas, 1990).

The migrating livestock damaged the crops of the indigenous people, in spite of the ordinances of 1574, which obliged the ranch owners to open up roads reserved for livestock to go from one place to the other, but most never obeyed. The irrigated, cultivated areas of the towns were what interested the ranchers, much more than the plains covered with opuntia or the bald mountains they crossed.

Forage

Livestock feeding was mostly provided from natural sources, and that included opuntia. Reproduction of livestock was spontaneous, and often the owners themselves were ignorant of how many beasts they possessed. Sheep and goats were husbanded under nomadic grazing; cattle, only on a small scale, were raised on ranches and specialized haciendas. The harsh environmental conditions affected the animals, and - coupled with losses from robbery, pests, disease, frosts, hail and severe drought - decimated the livestock, especially because a large proportion of the animals was raised in the arid regions.

A drought meant lack of drinking water and grass, followed by hunger, malnutrition, disease and finally death. This situation obliged the owners to leave the animals free to forage for themselves. The historian François Chavalier reported that in the years of drought animals died by the thousands (Chevalier, 1982).

Sources from the 16^th, 17^th and 18^th centuries state that the livestock ate grasses, stubble, maize and opuntia, among other things. In 1585, Juan González de Mendoza wrote that in the entire Kingdom of New Spain, the livestock fed on green plants and maize, which was the wheat of the Indians (Trabulse, 1993).

Chevalier (1982) reports that at the end of the 16^th century, the “encomenderos” (landlords) fattened their animals with maize, which they had, in abundance, thanks to tributes. The quality of the meat was linked to the quality of the maize or the grasses (Trabulse, 1993). As to the usefulness of stubble, in the 18^th century, José Antonio Alzate wrote:

“For some years I saw a subject who obtained an ear of Meztitlan, he sowed it in a small garden: the stalks grew to six or seven feet and produced three, four or more ears of large size. This excessive vegetation was not the effect of any preparation neither of the seed, nor of the fertility of the soil, because if he sowed another species of maize, the product corresponded to its nature. This experiment foresees great profits for ranch owners who would benefit if they sowed Meztitlan maize, besides the abundance of the fruit, tlazole, or straw, increases, which is so necessary for the livestock (Trabulse, 1992b).

As to the opuntia cactus used as forage, the newspaper El Nacional, of Mexico City, reported that during the colonial period there were mestizo farmers who planted opuntia in half of their farm plots to feed the animals, and in the other half they sowed maize and beans:

“... and when they judged the land to be worn out, they cut half the cactus pear as forage for the animals, especially the cattle, and the rest was planted in the agricultural land, which after two years was again used for ordinary crops, repeating the same operation of leaving the land to rest by planting cactus pear, which maintains the ground moist and magnificent grasses grow at the same time, preventing erosion of the land and providing abundant, moist, fresh grass for the livestock almost year-round (Anon., 1962).

INDEPENDENT MEXICO

When Mexico won its independence in 1821, the national territory consisted of a little more than 4 million km² which included the territories of Texas, New Mexico, Arizona and California, which passed to the USA in 1848. In these territories, opuntia was used as forage; once chopped up or singed, it was given to cattle (Flores and Aguirre, 1979), a practice also common in the Mexican states bordering the USA. This was confirmed by a study in Mexico at the end of the 19^th century by the German Karl Kaerger (1896), whose objective was to investigate agricultural aspects in which Germany could invest, especially considering the facilities given by the government of Porfirio Diaz to foreigners.

Livestock husbandry

Cattle raising developed in Mexico mostly in the northern part of the country. Enormous ranches were established and land was concentrated to such a degree that the Terrazas family owned almost the entire state of Chihuahua.

At the end of the 19^th century, massive sheep raising was conducted in the northeast of the country, especially in the states of Zacatecas, Tamaulipas and Chihuahua, where there were haciendas with 70 000 to 80 000 head of cattle head (Kaerger, 1986). Goats were abundant in Puebla, Zacatecas, Aguascalientes, Tamaulipas and San Luis Potosí, while cattle were raised basically in the north of Mexico and the coastal region of Veracruz, where improvement of the national breed with the introduction of Durham and Hereford bulls had begun. Outstanding among the pastures used for fattening were those located in the Huasteca, the northern coastal zone of Veracruz, and the southern coastal region of Tamaulipas (most of the state of Tamaulipas was dedicated to sheep and goat raising).

The forage

In the northern part of the country, the cowboys, besides riding horseback every day over a given area of the hacienda to guard the cattle from possible rustling, had the task of getting additional feed for the animals during the dry season. The feed was obtained by cutting agave plants, known as sotol, and chopping their leaves, and, more important, cutting opuntia pads and burning off the thorns so that the livestock could eat the pads, although often the plants were eaten where they were standing. The greatest opuntia populations were found in San Luis Potosí, Tamaulipas and Nuevo Leon, where the farmers could distinguish the following varieties:

* Nopal rastrero (creeping prickly pear): a cactus with a lateral growth form and consumed mostly by goats.

* Nopal cuyo: a thin cactus with few thorns; relished by cattle.

* Nopal cardón (O. streptacantha): a fruit species with broad pads. Its fruit is used to prepare a fermented drink, mixing it with maize grains, apples and cane alcohol. Cattle can eat it only during the dry season since in the rainy season it swells too much (Bazant, 1980).

* Nopal cegador (blinding prickly pear): Well eaten by cattle, although it can cause blindness if the thorns get into their eyes.

* Cardenche or joconostle: It has large cylindrical stems (trunk) and is preferred by live-stock.

* Tasajillo: similar to the cardenche type, but the stems are smaller and of lower quality. Goats eat its fruit (Kaerger, 1986).

A newspaper article appearing in the early 20^th century reported the enormous amounts of tunas of all kinds that were produced in San Luis Potosí. It points out that opuntia grew in the poorest land, in hard, cracked, alkaline soil, where there was no other sign of vegetation, far from fresh water springs, where there were more hills than flat land; this hilly land promoted cactus growth, and gave the landowner splendid profits, since they needed neither care nor expenditures of any kind.

“[The parts] of the prickly pear used are: the pads for feeding cattle, when they are fresh, and when they are dry they are magnificent fuel, and the tunas, from which a delicious fermented drink is made called colonche; also, an exquisite tuna syrup is made, as well as jams and taffy, and a liquor is also extracted from the tuna...” (Márquez, 1986)

Animals also ate other plants covered with thorns without singeing, such as mesquite (Prosopis spp), lechuguilla (Agave lecheguilla) (the northeastern agave, which is used to produce fibre), and huapile, a bromeliad which covers large areas. The lechuguilla is very nutritious, although it has the disadvantage of inducing the animals to become wild, as they need not drink water because of the juiciness of the leaves (Kaerger, 1986).

RECENT DEVELOPMENTS OF OPUNTIA IN MEXICO

Forage

The importance of opuntia as a forage plant in the 19^th century was the outcome of the need to feed livestock in the arid zones of the country, where the dry seasons are very long. Opuntia is an excellent feed for livestock (Flores and Aguirre, 1979).

Government interest in development of the arid zones, which accounted for 40% of the national territory, led to creation of the National Commission for Arid Zones (CONAZA) in 1970. This institution provided support to arid zones where it was not possible to obtain profitable grain harvests unless they were irrigated. CONAZA proposed a programme to grow and use wild plants such as opuntia, candelilla (Euphorbia antisiphylitica), lechuguilla (Agave lecheguilla), fibre yucca (Yucca filifera), and mesquite (Prosopis juliflora). According to a preliminary study of the 1970 census, over 50% of the cattle and sheep and almost 80% of the goats existing in the country were in arid zones. In these zones, opuntia became vital, because it provided some food and water for the animals (Villarreal, 1958).

Although during the first half of the 20^th century there were numerous species of wild opuntia, they began to disappear, mostly because of the excessive removal by merchants to supply foreign markets. Laws were passed to prohibit its export, but today the commerce in opuntia continues in different forms, with the consequent disappearance of some species (Granados and Castañeda, 1991).

The people of Northern Mexico have used opuntia as forage for many decades. At present the dairy industry in the arid zones of the north still use opuntia as forage. In 1966, 600 tonne of opuntia were used daily in feeding stabled dairy cattle in Monterrey, Nuevo León, and 100 tonne daily in Saltillo, Coahuila (Granados and Castañeda, 1991). Cattle and, above all, grazing goats and sheep, consume opuntia almost all year. The shepherd burns off the thorns from the pads that he selects, although sometimes the standing plants are singed (Flores and Aguirre, 1979).

The Ministry of Agriculture promoted opuntia plantations for forage in many regions. The gathering of opuntia for forage was banned in the states of Coahuila, Chihuahua, Nuevo Leon and Tamaulipas, and industrialization promoted. Cattlemen were barred from singeing opuntia thickets to ship them to market (Anon., 1961). The government of Zacatecas began a campaign to industrialize opuntia, especially the cardon type, abundant in the state (Anon., 1963a).

Reduction of the opuntia populations obliged the Ministry of Agriculture to set up a Programme for Genetic Improvement of Prickly Pear in 1961, at the Graduate College of the National School of Agriculture. The goal was to increase fruit production and improve cattle feeding in the semi-arid zones of the country, which largely depend on opuntia during droughts. The main objective was to obtain improved varieties, which would, besides producing high quality fruits, be spineless in order to use the pads to feed cattle (Anon., 1963b). By 1975, Mexican geneticists had produced several useful varieties (including cvs. CPF1, Pabellón and CPV1).

Opuntia production

Opuntia is not considered a regular forage crop and statistics on planted area and production were not reported until 1984, and then with little accuracy. Although the cultivated area has been growing steadily, the figures are low: 22 ha in 1984, rising to 422 ha in 1997 (SARH, 1984 to 1989; SAGAR, 1990 to 1997). Forage production has been reported in the northern and central part of the country, as well as Southern Baja California. Opuntia used for forage production is not directly assessable compared to traditional crops because of the wide utilization of wild stocks.