| Agroforestry in the Pacific Islands: Systems for Sustainability (1993) |
|5 Agroforestry in Polynesia|
Rarotonga and Aitutaki, the Cook Islands
Rarotonga and Aitutaki, two small islands in the southern Cook Islands, have agroforestry systems that have been subjected to relatively high population densities as well as to strong pressures from urban growth and the commercialization of agricultural production.
Rarotonga, with a total land area of 67 sq km, is a high basaltic island with a rugged forested interior rising to 652 metres, areas of highly degraded bush and fern-clad hills, deep well-watered valleys, and a fertile low-lying, somewhat swampy coastal plain fringed by a narrow, slightly-raised sandy coastal strip. With Mangaia, the second-highest island in the Cook Islands, reaching only 168 metres, the native upland vegetation of Rarotonga is not found elsewhere in the Cook Islands (Merlin 1985,84).
Agricultural activities in Rarotonga have traditionally focused on taro cultivation in the rich soils of the swampy lowlands and the alluvial and colluvial soils of stream valleys surrounding the mountainous interior, with diversified agroforestry and other root cropping being practiced throughout these areas, as well as on extensive areas of colluvial soils on the lower slopes and interfluves of the interior and in home gardens in villages located on the lower slopes of the interior and on the well-drained coastal strip. The current population of Rarotonga is estimated to be over 10,000, which constitutes over half of the 15-island country's population.
Aitutaki, a smaller island lying some 225 km north of Rarotonga, has a total area of 19.9 sq km and an estimated 1981 population of 2,335 (Douglas and Douglas 1989). The land area consists of a somewhat lowlying volcanic island, rising to a maximum elevation of 137 metres at Maunga Pu (Sykes 1976), with limited areas of alluvial valleys and coastal plain surrounding upland agricultural areas and highly degraded scrub lands and fern lands at higher elevations. There are also a number of low-lying coralline and volcanic reef islets, or motu, surrounding an extensive lagoon, "generally considered to be one of the most beautiful in the Pacific" (Douglas and Douglas 1989, 53).
Agroforestry activities on both islands have been seriously affected by emigration, heavy emphasis on export cash cropping, and increasing monetization, as well as other urban-biased developments, particularly tourism, and increasing educational, economic, social, and nutritional dependence on New Zealand.
Because of the unusual political status of the Cook Islands, first as a New Zealand colony since the turn of the century and then, since 1964, as a self-governing state in free association with New Zealand (with Cook Islanders remaining New Zealand citizens with free access to New Zealand), there has been steady emigration of Cook Islanders to New Zealand since World War II, with well over half of all Cook Islanders now residing there (Douglas and Douglas 1989). Remittances from overseas Cook Islanders in New Zealand, as well as from those in wage employment on Rarotonga, to outer islands such as Aitutaki constitute the major source of income for many families.
The main agroforestry zones on Rarotonga and Aitutaki are:
Aitutaki, being a smaller, older, lower island than Rarotonga, has very limited areas of poorly drained lowland and virtually no indigenous upland forest.
Home and village gardens
Because of the emphasis on commercial cropping and the highly derived nature of the vegetation at lower elevations, especially on Aitutaki, it is in home and village gardens that one finds agroforestry at its most diverse. On both Rarotonga and Aitutaki, home agroforestry is characterized by a wide range of fruit-trees, ornamental trees and shrubs with fragrant flowers or leaves, and a number of other useful trees, which serve as a matrix for lawns, structures, and scattered flower gardens.
Most common among the fruit or edible-seed trees are coconut palms, breadfruit, mango, citrus trees, papaya, avocado, guava (Psidium guajava and P. cattleianum), Tahitian chestnut (Inocarpus fagifer), the red-bead tree (Adenanthera pavonina), sweetsop and soursop (Annona squamosa and A. muricata), Polynesian vi-apple (Spondias dulcis), Malay apple (Syzygium malaccense) and beach almond (Terminalia catappa). Among the citrus trees, species such as limes and lemons, which are commonly required for marinading raw fish (ika mata) and which are not normally planted in the larger commercial citrus plantations, are usually found near homes. Mandarin orange, grapefruit, and the orange are also common in home gardens.
Other fruit-trees occasionally found in home gardens include jakfruit (Artocarpus heterophyllus), carambola (Averrhoa carambola), the star apple (Chrysophyllum cainito), koko (Inga edulis), tamarind (Tamarindus indica), the Pacific fan palm (Prichardia pacifica), and a range of fruits, all referred to locally as vinevine, including Surinam cherry (Eugenia uniflora), white mulberry (Mows alba), governor's plum (Flacourtia ramontchi), acerola (Malpigia glabra), and the sea grape (Coccoloba uvifera).
Common non-fruit trees found in home gardens include Norfolk Island pine (Araucaria heterophylla), banhinia (Bauhinia spp.), kapok (Ceiba pentandra), flame tree, or poincianna (Delonix regia), coral, or dadap, tree (Erythrina variegata), beach hibiscus (Hibiscus tiliaceus), pandanus (Pandanus spp.), bay rum tree (Pimenta racemosa), frangipani, or plumeria (Plumeria rubra and P. obtusa), African tulip tree (Spathodea campanulata), and yellow bells (Tecoma stans).
Among tree-like shrubby species, the Tahitian gardenia (Gardenia taitensis) is particularly common and very important, along with the frangipani, in the production of the ubiquitous flower garlands, or lets, that are still of considerable cultural and economic importance, both for everyday use and for the expanding tourist industry. Other common shrubby species, most of which are referred to as kapaie (literally hedge), commonly planted as living hedges or fences or as ornamentals, include a number of panax species (Polyscias guilfoylei, P. scutellaria, P. balfouriana, and P. tricochleata), the copper leaf, or beefsteak, plant (Acalypha amentacea), croton (Codiaeum variegatum), cordyline (Cordyline fruticosa), the caricature plant (Graptophyllum pictum), and the common hibiscus (Hibiscus rosasinensis).
Coastal and strand agroforestry
Because the sandy low-lying coastal zone and smaller offshore islands are commonly owned and used by the same families who actively cultivate inland gardens, these areas can be seen as integral parts or extensions of the agroforestry system. Moreover, such areas border or extend into agricultural areas as well as being integral components of coastal home gardens.
The dominant trees or tree-like shrubs in the outermost zones, which are most exposed to salt spray, include Messerschmidia argentea, Leucaena insularum, Sophora tomentosa, and the often dominant saltbush, or halfflower, Scaevola sericea. Two very hardy plants known locally as ngangie, Pemphis acidula and Suriana maritima, which seem to be absent on Rarotonga- possibly because of human clearance, although they may never have been present (Sykes, 1976) are common on the reef islets, or motu, of Aitutaki.
In more sheltered areas on Rarotonga, beach hibiscus (Hibiscus tiliaceus), Indian mulberry (Morinda citrifolia), and Pipturus argenteus are common, with Hibiscus tiliaceus forming dense stands. Emergent coconut palms commonly dominate this somewhat shrubby vegetation formation, which merges on its inner margin with semi-open, semi-natural or planted coconut groves (Sykes 1976). Similarly, on Aitutaki, Hibiscus tiliaceus, often along with Pandanus tectorius, dominates large areas along the coast, especially between Tautu and Vaipae, where lateritic soils overlying the volcanic bedrock reach the sea (Sykes 1976).
Where the indigenous vegetation has not been cleared for coconut monoculture, or in coastal areas where indigenous strand species have not been felled or replaced by home gardens, dominant large trees include Barringtonia asiatica, Calophyllum inophyllum, Hernandia nymphaeifolia, and Pisonia grand is, with Casuarina equisetifolia being abundant locally in coastal areas on both Rarotonga and Aitutaki. Guettarda speciosa and Pandanus tectorius are also quite common locally in coastal areas of Aitutaki, especially near the Ootu airstrip, and on some of the reef islets. Thespesia populnea is reportedly found on some reef islets of Aitutaki (Sykes 1976), and, along with Cordia subcordata (both endangered coastal strand species highly valued for wood carving in the Cook Islands), it is currently being planted along roads on the coastal strip of Aitutaki as part of current nationwide conservation activities.
On Aitutaki, coconuts are similarly ubiquitous emergents along sheltered lagoons, as well as the dominant tree on the more productive coastal fringe areas, with large numbers of regularly-spaced palms having been replanted after World War II deforestation to make way for an airstrip. Most palms, however, except some along the north coast of Aitutaki, which have been planted as part of a coconut rehabilitation scheme, are irregularly spaced, often in dense stands (Johnston 1967).
Agroforestry in poorly drained lowlands
On Rarotonga there are extensive poorly-drained agricultural lowlands, or pa'i, which constitute the most important taro-growing areas on the island. They are dominated almost entirely by excavated and mulched swamp taro (Colocasia esculenta) cultivation and fallowed taro beds in various stages of abandonment. Scattered throughout these areas are a wide range of planted or protected trees, usually along the bunds and pathways between plots or on scattered areas of high ground. Although only limited studies of these areas were conducted, the main trees in these pa'i areas include coconut palms, Tahitian chestnut, mango, Polynesian vi-apple, guava, Hibiscus tiliaceus, the jambolan (Syzygium cumin)), and banana and plantain cultivars. Although not the dominant vegetation, these scattered trees add important diversity and welcome shade and snack foods for gardeners in these highly productive agricultural areas, which have provided Cook Islanders with their traditionally important staple, taro, for over a thousand years.
On Aitutaki, areas under swamp taro cultivation were very limited in extent and found only in small patches inland and along the east coast. Where such swamp taro gardens exist, similar tree species to those on Rarotonga were often associated with them, particularly Hibiscus tiliaceus, which bordered some gardens.
Agroforestry in the uplands and inland gardens
Well-drained upland and interior garden areas extend inland from the coastal strip and the poorly drained taro swamps up to heights of 50-200 metres on Rarotonga and up to some 100 metres on Aitutaki. In these areas, traditional diversified agroforestry once predominated, but mostly has been gradually replaced by monocultural root cropping and institutional plantation culture of citrus, pawpaw, and tomatoes on Rarotonga and citrus, bananas, and tomatoes on Aitutaki. Johnston's (1967) study of agriculture on Aitutaki and Wilder's (1931) Flora of Rarotonga provide some indication of what the system was like prior to World War 11.
Whereas on Rarotonga there are still scattered groves of trees in some areas, particularly in well-watered valleys and beyond the limits of current cultivation, these are now virtually absent on Aitutaki, where there was an absence of primary forest by the early 1960s as a result of the "rotational bush fallow" agricultural system in which areas of active garden production for a given family were rotated "through a fixed area of fallow grass or woody plants where woodland is not allowed to regenerate" (Johnston 1967,28).
In both areas, permanent cultivation or protection of useful trees such as coconuts, citrus, breadfruit, mango, Tahitian chestnut, avocado, papaya, oceanic Iychee (Pometia pinnata), matakoviriviri (Adenanthera pavonina), kapok, and candlenut (Aleurites moluccana), and a wide range of banana and plantain cultivars - was also an integral part of the system.
Even the export citrus industry, which flourished from the late nineteenth century until the 1930s, was based on the "haphazard" (in Johnston's view) production of dispersed "wild" orange trees, which had been incorporated into the subsistence economy and were found scattered among other tree crops (Johnston 1967, 50-51). As late as the 1950s, these "wild oranges," which included fruit from trees scattered in the forest beyond the limits of cultivation, still constituted the overwhelming proportion of citrus production and exports (Johnston 1951, 130).
Evidence indicates that a fallow period of 10-20 years, followed by a cropping period of 2-4 years, was the traditional fallow-crop cycle. By 1960, however, fallow periods had dropped to only 5 years, and to as low as 1-2 years in more accessible areas closer to villages, with the cropping period remaining the same (Johnston 1967, 34-35), a process that explains the absence of primary forest and a scarcity of secondary forest in the gardening areas.
Although the traditional criterion for selecting garden sites was sufficient regrowth of mature secondary forest, land that had lain fallow for 10-20 years was extremely limited (Johnston 1967, 29). What forest did exist usually consisted, as it does today, of limited areas of relatively mature, almost homogeneous, stands of au (Hibiscus tiliaceus) and, in some cases, guava. Priority in use of such areas was given to bananas, which bear for 5-10 years on one plot, although existing banana areas and individual family needs were taken into account. Yams were almost always planted on newly cleared land, where uncleared trees and stumps provided trellising or support for the vines. Other non-tree and root crops were usually planted on land cleared from younger secondary forest, areas of bush-fallow, or in succession after the harvest of the previous crop, although tomatoes were also commonly planted on recently cleared fallow land, but generally in less mature areas that were relatively easy to clear (Johnston 1967, 15, 21-30).
Plot histories indicated that bananas were always planted for a minimum of 5 years, with some varieties for at least 10 successive years. Cassava was generally planted for 2 years in succession, although sometimes for 4 years, whereas yams, sweet potatoes, tan nia (Xanthosoma taro), and tomatoes were generally planted only once in succession on a given plot, although tannia was occasionally planted for 2 years (Johnston 1967, 33).
Of the major food crops, coconuts excepted, cassava was most common, covering 39 per cent of the area under crops. Reportedly introduced by the missionaries in the last century to supplement mission funds, cassava spread rapidly, possibly because of the prestige growers received by contributing to the church and the ability of cassava to grow in the conditions of relative water scarcity and declining soil fertility on Aitutaki, conditions that restrict the growth of wetland tarot Bananas or plantains cover 29 per cent, and tannia (Xanthosoma sagittifolium) 12 per cent. Other crops such as sweet potato, taro, yams, and minor crops such as melons, pumpkins, and onions, covered 7.8 per cent, and the two major commercial crops at the time, oranges and tomatoes, constituted 7.6 per cent and 4.6 per cent of the area respectively, making up the balance of the area (Johnston 1967, 14-21).
Although second in importance in terms of area, banana or plantain plots were the most common, with over two-thirds of all gardens containing them as one of several crops or as the sole crop, with some plots bearing up to 15 years. Moreover, such plots were the most localized and often at a greater distance from the village than root crops (Johnston 1967, 13-14).
Cassava and sweet potato were almost always planted as monocultures, and bananas and tannia usually as monocultures, although 18 per cent of tannia plots had been intercropped with bananas for 23 years. Intercropping was characteristic only of yam plots, which were often interplanted with bananas or tannia and occasionally with cassava.
Tree crops were scattered throughout garden areas, as were mixed groves of valuable trees. Coconut palms, the dominant crop on the coastal fringe, were found as isolated individuals or irregular clusters. Tahitian chestnut, mango, breadfruit, papayas, rough lemon, Malay apple, Polynesian vi-apple, and avocados, along with the widespread wild "native" orange and a range of other useful trees, including kapok, the banyan (Ficus prolixa), mata'oi (Cananga odorata), and candlenut, were the main trees, although breadfruit was more commonly found around villages, particularly on Aitutaki (Johnston 1967, 16).
On Rarotonga, where extensive areas of low-lying swamp taro beds and systems of irrigated taro terraces existed historically to take pressure off interior and upland garden areas, trees were more numerous than on Aitutaki, with a much greater range of trees being found either planted or naturalized in interior and upland agricultural areas.
Hibiscus tiliaccus was, and still is, the commonest and often dominant tree, with Tahitian chestnut (Inocarpus fagifer) and the candlenut (Aleurites moluccana) being particularly common in valley entrances and on lower slopes on Rarotonga. Formerly cultivated trees that have become extensively naturalized on Rarotonga include Cecropia palmata, Inga edulis, mango, and jambolan (Syzygium cumin)). Commonly found around garden areas, especially on the lower slopes of the mountainous interior, are Bischofia javanica, Homalium acuminatum, and Xylosma gracile, which Sykes (1976) believes to be "almost certainly . . . principal components of the original forest." Homalium acuminatum (moto) - the durable wood of which was formerly important in canoe construction and which was formerly "common from sea-level to 1000ft" - is one of the few native trees still occasionally found around plantations where it "was most likely the 'most common dominant' before human disturbance" (Cheeseman 1903; Sykes 1976, quoted in Merlin 1985, 90).
Other species found in the more disturbed areas of the lower montane slope forest include Elaeocarpus rarotongensis, Weinmannia rarotongensis, Macaranga harveyana, Planchonella grayana, and Terminalia glabrata, with Fitchia speciosa found in the more recently disturbed sites (Merlin 1985, 89). In the case of Bischofia javanica, some authorities such as Whistler (1980a) and Thaman (1988g) believe that B. javanica could have been a deliberately cultivated aboriginal introduction that, because of its widespread cultural importance as a source of dye for tape cloth, its use as a medicinal plant, its value as a sign of soil fertility, and its ability to withstand human abuse, remains as a relict or a possible natural dispersal from ancient garden areas. It was particularly common in most valleys and hillsides at lower elevations in the 1920s (Wilder 1931, 70), is common in low-elevation disturbed forest (Merlin 1985), and is still quite common on lower mountain slopes and surrounding old irrigated taro terraces, such as in the Takuvaine Valley.
The pattern of shifting cultivation amongst scattered fruit-trees and other useful trees and permanent tree groves has, however, been significantly altered because of increasing emphasis on commercial and subsistence monocropping, which began as early as last century and which has accelerated since World War II with the systematir institutional promotion of comercial export cropping coupled with the increasing monetization of the economy. The earliest changes were probably the introduction of cassava by the missionaries to raise funds for the church and tannia (Xanthosoma sagittifolium) - both of which grow well on drier upland soils. Both are commonly grown as monocrops and are rarely intercropped because of their ability to grow under conditions of declining soil fertility. Increased cassava cultivation, in particular - cassava is commonly planted up to four times in succession on the same plot of land - is a major factor in deforestation and agrodeforestation and the movement towards shorter fallow periods. On Aitutaki, cassava, in addition to being a prestige crop because of its association with "Christians contributing to the church," has also been an important supplementary cash crop for export production of starch.
The trend towards agrodeforestation continued in the 1930s, when intensive clearing of wild oranges to obtain land for seasonal planting of tomatoes took place, and when increasing dependence on cash incomes from expanding employment opportunities in areas such as teaching, the medical profession, and government service, coupled with contract work in the phosphate mines on Makatea in French Polynesia and emigration and associated cash remittances, began "drawing people away from the soil" (Johnson 1951, 125).
About the same time, due to falling production from wild orange trees, many of which were dying of old age and uncontrolled disease, a citrus replanting scheme was instituted by New Zealand authorities to shift the production from "haphazard" production of dispersed wild oranges to "scientific plantation agriculture." The scheme was organized so that, once the prospective owner had established secure tenure to a suitable piece of land, the administration took over and "established and matured the young plantation." The "considerable initial and recurrent costs for labour, fertilizers and machine hireage" were charged against the owner's account, to be paid when the trees began to bear, with the owner's sole responsibility being to arrange for the picking of the fruit and, in some cases, weeding and pruning, although few owners in Aitutaki exercised this option (Johnston 1967, 5).
Initially, 100 citrus plots were established on Rarotonga, each of 1.5 acres and containing 90 trees. By 1950 some 150 plots had been established on Rarotonga on the gently sloping garden lands inland from the low-lying taro swamps, or pa'i. The scheme also provided for the establishment of 50 acres on Aitutaki. Johnston (1967, 130) relates that, during this time, many existing tree groves and orange plantings were "devastated" for tomato cultivation, for "new" orange orchards, and commercial cropping of water melon, sweet potato, and tannia for the expanding local urban market. Although orange production was the main focus of the citrus scheme, limited quantities of mandarin orange or tangerine and grapefruit were also processed at the local fruit-processing factory on Rarotonga or exported by sea to New Zealand during the 1960s and 1970s (Department of Agriculture 1979).
During this period, the only government-supported activities related to agroforestry were the planting of dadap (Erythrina variegata) between alternate orange trees, with the foliage being trimmed to provide green manure; and the planting of jambolan (Syzygium cumini), Albizia falcataria, hibiscus (Hibiscus rosa-sinensis), and hedge panax (Polyscias guilfoylei), along with dadap, as wind-breaks or shelterbelts, or with the matured Albizia to provide timber for fruit-cases (Johnson 1951, 129-130).
Unfortunately, production fluctuated, even in the 1960s and 1970s when production was at its peak, with returns to growers being small, and with resultant widespread indebtedness due to charges against the owners, which increased at a faster rate than their repayment (Johnston 1967, 52). Moreover, by 1978, many of the citrus plantings were in a rundown state or beyond their "economic life" of approximately 25 years, thus requiring replanting programmes to rejuvenate the industry (APU 1978). Ward and Proctor (1980, 375) suggest that serious consideration should be given to the possible "winding up" of the citrus industry and the use of land for other purposes, because in only one year during the 1970s did real gross receipts exceed real purchased input costs in the citrus industry, with the net income of producers during other years being "wholly financed by subsidies."
The economic failure of the citrus industry, the low prices received for tomato exports, and a continuing focus on export diversification have led the government and local farmers to look for other commercial agricultural alternatives. Most prominent have been the implementation of banana replanting and extension schemes on both Rarotonga and Aituaki in the 1960s to increase banana exports to New Zealand and the official promotion of plantation culture of papaya for air-freight export to New Zealand. There was also an unsuccessful attempt to establish a commercial pineapple project on Rarotonga in 1966 (Tudor 1972, 143). Also significant have been the increasingly capital-intensive and monocultural production of taro, sweet potato, tannia, and cassava, both for the rapidly expanding local market and for export to New Zealand as well as for subsistence consumption.
As in the case of citriculture, subsidization of production of such activities has been considerable. In the case of the Aitutaki Banana Scheme of 1964, which established a 50-acre nursery and encouraged replanting with free planting material and loans for the purchase of fertilizer, the estimated cost was NZ$106,000, of which NZ$70,000 represented advances to growers. By 1970, 500 acres had been planted under banana replanting schemes on both Aitutaki and Rarotonga (Tudor 1972, 143). Unfortunately, monocultural banana production has always been beset with disease problems, most notably black-leaf-streak fungus and bunchy-top virus, and widespread devastation due to periodic tropical cyclones, not to mention marketing problems related to unreliability of ship transport and competition from Ecuadorean bananas. These problems, plus an increasing focus on the commercial production of papaya and, to a lesser extent, beans and capsicum for air freight to New Zealand, and on rapid tourism development since the opening of the new international airport in 1973, brought about the cessation of banana exports from Rarotonga in the late 1970s, leaving Aitutaki as the sole producing area for export production of bananas in the Cook Islands. As of July 1988, despite a devastating tropical cyclone in December 1987, 150 growers on Aitutaki had 350 acres (141 ha) under banana monoculture, with the individual holdings ranging from 2 to 7 acres. Disease problems and irregularity of transport, however, continue to hinder development of the industry.
Upland forest agroforestry
Although technically not part of the agricultural system, the forest of the hill slopes and mountainous interior of Rarotonga, which in most areas seems to be in nearly its original state (Sykes 1976), contains numerous species of widespread cultural utility and ecological importance and, like the coastal strand forest, must be seen as an extension of the agroforestry system. Such areas take on greater importance as refugia for endangered species as agrodeforestation proceeds in more accessible garden areas. As argued by Merlin (1985, 81), the preservation of the upland forest of Rarotonga, where over 92 per cent of all woody plants are either indigenous or endemic, is particularly important because "the native coastal and lowland vegetation of this high volcanic, tropical island has either been completely removed or heavily disturbed."
The major species in the upland forest include Fitchia speciosa, in more open sites, and Homalium acuminatum, as the dominant in the lowerslope forest areas. Other common species include Hibiscus tiliaceus, which is very common up to 250 metres, Aleurites moluccana, Elaeocarpus rarotongensis, Xylosma gracile, Pittosporum rarotongensis, Bischofia javanica, Macaranga harveyana, and Weinmannia rarotongensis, with Planchonella grayana and Terminalia glabrata being more localized, and the recent introduction, Cecropia palmata, scattered throughout some areas of forest. Common understorey shrubs include Canthium barbatum, Ixora bracteata, Macropiper latifolium, Mertya pauciflora, and, sometimes, Alstonia costata. Numerous lianas of considerable cultural importance, such as Freycinetia wilder) (kiekie), Alyxia elliptica (maire rakau), and Jasminum didymum, are also present (Merlin 1985; Sykes 1976).
On the wetter, higher slopes, Metrosideros collina is dominant, with Fitchia speciosa, Elaeocarpus rarotongensis, Pittosporum rarotongensis, Weinmannia rarotongensis, and, to a lesser degree, Coprosoma laevigata, Xylosma gracile, Geniostoma rarotongensis, Morinda forester), and a small shrub, Vaccinium cereum, being present. On ridge crests, Fagraea berteriana is most dominant, with other species including Fitchia speciosa, Homalium acuminatum, and, to a lesser extent, Canthium barbatum, Alyxia elliptica, Metrosideros collina, Hibiscus tiliaceus, Coprosoma laevigata, and Mertya pauciflora.
Increasing monoculture and agrodeforestation
The impact of export-oriented monocultural agricultural development and increased monocropping of root crops on both Rarotonga and Aitutaki have led to the widespread recent removal of even common useful trees, such as beach hibiscus (Hibiscus tiliaceus), Tahitian chestnut, mango, kapok, Polynesian vi-apple, candlenut, coral tree (Erythrina variegata), matakoviriviri (Adenanthera pavonina), and even coconut palms, as well as recently introduced species such as jambolan (Syzygium cumin)) and Albizia falcataria on both islands. Even the cultivation of a range of banana cultivars, which have long constituted dominant staples, has declined dramatically. Whereas on Aitutaki, there remain few, if any, forest stands or tree groves, except for stands of Hibiscus tiliaceus, on Rarotonga there are large areas of native upland forest, and tree groves can still be found in some areas, with traditionally important species still scattered throughout low-lying swamp and and in upland garden areas.
Some trees that were formerly abundant, such as mata'oi (Cananga odorata), the flowers of which were highly valued for garlands and scenting coconut oil; Malay apple, or ka'ika (Syzygium malaccense), and oceanic lychee, or tava (Pometia pinnate), both with edible fruit; mati (Ficus tinctoria) and ava (Ficus prolixa), the best fibre of which was so important in the manufacture of bark cloth; tou (Cordia subcordata) and miro (Thespesia populnea), two of the most valued woods for wood carving; and other species of widespread medicinal importance throughout Polynesia, such as Glochidion ramiflorum, Alphitonia zizyphoides, and Grewia crenata, to mention only a few, are increasingly rare, and, in some cases, endangered or possibly extinct.
The development processes that have been described in this section have led on Rarotonga and Aitutaki to agrodeforestation and to a cultural abandonment of, and failure to replant, traditionally important trees. The antiarboreal pressures are worse in these islands than almost anywhere else in the Pacific, with the possible exceptions of Nauru and Hawaii. One could go so far as to suggest that a combination of factors has brought about an "agrodeforestation of the mind" in a generation of young Cook Islanders, who neither know the names of their trees nor are able to find one!