Cordia alliodora (Ruiz & Pav.) Oken

Laurel, Capá Prieto

Boraginaceae -- Borage family

L. H. Liegel and J. W. Stead

Laurel (Cordia alliodora) is a tropical hardwood that grows from Mexico to Argentina. It is also known as capá prieto. The species frequently serves as shade for coffee trees and farm animals. The wood is easy to work and the dark colored heartwood is a favorite of woodworkers for fine carpentry.

Habitat

Native Range

Laurel is the most widely distributed species of Cordia, a genus including some 200 species ranging from shrubs to large trees. The geographic range is quite extensive, from latitude 25° N. to 25° S., or roughly from the State of Sinaloa in Mexico to Misiones in Argentina (30). The range also includes most of the West Indies (16). Laurel is thought to have been introduced to Jamaica (13) and was first planted in Surinam as an exotic plantation species in 1967 (36). It has also been planted as an ornamental in Florida (16). Local distribution maps are not generally available, except for Mexico (7), Colombia (37), and Puerto Rico (16) where ranges are given for both geographical and political regions. In Puerto Rico laurel grows in more than half of the municipalities, in 8 of 13 State Forests, and in the Luquillo Experimental Forest Biosphere Reserve.

Climate

Laurel reportedly grows best in Tropical Moist to Tropical Wet Forest life zones (11,12) where mean annual rainfall ranges from 2000 to 5000 mm (80 to 200 in) and mean annual temperature is 24° C (75° F). But in Trinidad (21) best growth of laurel was observed outside rain forests where annual rainfall was between 1270 and 1900 mm (50 to 75 in). The natural distribution of laurel in Puerto Rico seemed to follow this trend (19). In Central America and the West Indies, laurel grows in Tropical or Subtropical Dry Forest life zones; mean annual rainfall is about 750 to 2000 mm (about 30 to 80 in) and mean annual temperature is from 25° to 27° 0 (77° to 81° F). Growth is much slower and form is less impressive in the drier areas. In Puerto Rico laurel grows mainly in coastal Subtropical Moist Forest or in the Subtropical Wet Forest uplands (17) where mean annual rainfall ranges from about 1000 mm (40 in) to 3500 mm (138 in) or more. Less frequently in Puerto Rico it occurs in Subtropical Dry Forest where mean annual precipitation is between 600 and 1000 mm (24 and 40 in).

Soils and Topography

The altitudinal range of laurel is broad, from almost sea level in several countries, including Puerto Rico, up to 2000 in (6,560 ft) in the Colombian highlands. More commonly, it grows below 500 m (1,640 ft). Laurel grows best on well-drained, medium-textured soils and does not tolerate either poor internal drainage or water-logging. But it is not exacting in nutrient requirements, adapting well to degraded and abandoned areas once used for row crops, pasture, or shifting cultivation. Topography suited to laurel ranges from flat coastal lowlands, having deep infertile sands and little organic matter (Entisols or Oxisols), as in Surinam (36), to very dissected mountainous uplands, with deep, fertile volcanic soils high in organic matter (Andepts-Inceptisols), as in Colombia and Costa Rica (29). In Puerto Rico, laurel grows on shallow soils of the moist volcanic uplands (Inceptisols), on deep-red clay soils of the moist to wet volcanic uplands (Ultisols), and on shallow soils over limestone (Alfisols).

Associated Forest Cover

Laurel is associated with other pioneer species common to roadsides or gaps in mature forests, gallery forests, or savannas that are subject to natural or human disturbances. Some of these, yagrumo hembra or trumpet-tree (Cecropia peltata) and yagrumo macho or matchwood (Didymopanax morototoni), have extensive ranges that overlap that of laurel throughout the West Indies and the tropical Americas. In the Subtropical Dry Forest of Puerto Rico, laurel grows with almacigo or turpentine-tree (Bursera simaruba), guayacan or common lignumvitae (Guaiacum officinale), and the common naturalized exotics, bayahonda or mesquite (Prosopis pallida) and tamarindo (Tamarindus indica). In Subtropical Moist Forest it is associated with roble blanco or white-cedar (Tabebuia heterophylla), cedro hembra or Spanish-cedar (Cedrela odorata), algar-robo or West-Indian-locust (Hymenaea courbaril), jaguey blanco or shortleaf fig (Ficus laevigata), and the common naturalized exotics, flamboyan or flamboyant-tree (Delonix regia) and caoba dominicana or small-leaf mahogany (Swietenia mahagoni). It also grows on disturbed tabonuco forest type (Dacryodes excelsa), along with yagrumo macho and guano or balsa (Ochroma pyramidale). Tabonuco is the mature natural forest remnant of Subtropical Wet Forest (17).

Life History

Reproduction and Early Growth

Flowering and Fruiting- In Costa Rica, laurel reaches sexual maturity within 5 to 10 years (12). Some Costa Rican provenances have flowered at 4 years and produced viable seed at 5 years when planted in Surinam (36).

Flowers are perfect and crowded on a widely branched terminal panicle 10 to 30 cm (3.9 to 11.8 in) across. The calyx is cylindrical with 11 prominent ribs. The corolla is white with persistent oblong lobes, 5 to 7 mm (0.2 to 0.3 in) long and 1.5 to 3.5 mm (0.06 to 0.14 in) wide. There are five white stamens that are erect and protrude well beyond the exserted style, which is two-forked, each fork having two broad stigmas (16,30).

Flowers are perfect and crowded on a widely branched terminal panicle 10 to 30 cm (3.9 to 11.8 in) across. The calyx is cylindrical with 11 prominent ribs. The corolla is white with persistent oblong lobes, 5 to 7 mm (0.2 to 0.3 in) long and 1.5 to 3.5 mm (0.06 to 0.14 in) wide. There are five white stamens that are erect and protrude well beyond the exserted style, which is two-forked, each fork having two broad stigmas (16,30).

Overall phenology is quite variable across the range, a common phenomenon for tree species having such extended ranges. Major flowering in Central America occurs from February through March (30) and extends through May at least in Costa Rica (24). In the southern part of the range, as in Surinam, flowering occurs earlier, from December through January (36). In Puerto Rico there are no marked wet or dry seasons, and flowering takes place in almost any season (16). Laurel flowers throughout the year in Colombia and Ecuador too, but there is altitudinal variation; the high wet areas flower early in the year, and low dry areas flower later on, into July and August (23). Pollination is by wind or Lepidoptera, and perhaps by bees (12). Trees bear masses of flowers that are quite conspicuous from great distances. If surveys are synchronized with anticipated flowering times, regional or local distributions can be determined easily and with reasonable accuracy (30).

Fruits are cylindrical and ripen within 1 to 2 months after flowering commences. Nutlets are oblong, one-seeded, about 6 mm (0.25 in) long. Seeds are wind dispersed, yet they can persist on the trees a few weeks after ripening. Seedfall is usually quite variable since laurel flowers throughout the year. In Central America maximum seedfall is usually in April and May (33).

Seed Production and Dissemination- A persistent corolla acts as a parachute for seed. Individual trees produce 2 to 8 kg (4.4 to 17.6 lb) of seeds at 42,000 to 100,000 seeds per kg (19,100 to 45,400 seeds/lb) (30,33,36). Based on provenance collection work by the Oxford Forestry Institute (OFI) at Oxford University in the United Kingdom (30), the optimum procedure is threefold:

  1. Collect fruits when they change color from green to brown by shaking the entire tree or individual branches so that seeds or fruits fall onto netting or sheets. Under normal conditions the shaking and collection process should precede natural seedfall by 2 to 3 weeks. Only ripe seeds should be collected; fruits should not be pulled off branches.
  2. Reduce seed moisture content to 10 percent or less by drying in forced-draft ovens at about 70° C (158° F). In OFI experience, seeds collected by shaking before natural seedfall usually have a moisture content of 10 percent or less. Evidence from Costa Rica suggests that sun drying may be harmful to seeds.
  3. Store seeds at low humidity and temperature near 5° C (41° F) in screwtop containers. Un-refrigerated seeds can lose all viability within 5 or 6 months (33). Seeds collected and processed according to OFI recommendations have maintained good viability and shown 50 to 70 percent germination after 3 years in storage. When withdrawn from refrigeration, seeds should be germinated soon afterwards (30).

Seedling Development- Germination is epigeous. Seeds of laurel (fig. 1) germinate within 5 to 20 days after seedfall if there is sufficient soil moisture and a good mineral seedbed. Germination and nursery practices vary among countries currently planting laurel for research or commercial purposes. Wildling stock was successful in Puerto Rico in the late 1940's (20). Planting on mounds and plowing or burning with subsequent protection of sown seeds has been successful in Costa Rica (31). In Surinam, seeds are sown directly into plastic bags or young seedlings are dug up from specially prepared seedbeds located directly beneath designated seed trees (36). In Colombia, seeds are directly seeded onto nursery beds. The yield is about 20,000 seedlings per kilogram (9,100/lb) of seed, but only the most vigorous seedlings are transplanted into plastic bags from germination trays (29).

Several kinds of soil mixtures have been used for nursery beds or bagged seedlings. These include clay in Belize; sterilized, washed riversand in Nepal; well-tilled, fertile subsoil in Colombia; and a mixture of equal parts of clay, sand, and black earth in Brazil (30). In Colombia, germination has been poor using sand/soil mixtures (2). Small-grained vermiculite has been more successful in Costa Rica than conventional sand or loam soils (12). There seem to be no particular requirements for sterilization of soils.

Little consistency appears yet in determining optimum seedling size for transplanting or outplanting (30). Reported transplanting criteria for seedlings are 3 cm (1.2 in) tall in Brazil, 14 days old in Nigeria, 2 months old in Belize, the four-leaf stage in Ecuador, and the two-full-leaf stage in Fiji. Outplanting has been done after seedlings spent 10 months in the nursery in Belize, 5 months in Liberia, 5 to 8 months in Surinam, and 2 to 6 months in Costa Rica (30). Outplanted seedlings in Colombia are at least 15 cm (5.9 in) tall, and the recommended minimum lower stem diameter is 20 mm (0.8 in) (30). Stump planting, using a lifted seedling trimmed to 10 to 15 cm (4 to 6 in) of roots and 5 to 15 cm (2 to 6 in) of stem, is now probably the most preferred outplanting technique.

Initial seedling growth after outplanting is usually rapid. Plants have grown about 2 to 3 m (7 to 10 ft) per year after 3 years in Surinam (36). Single individuals from Trinidad and Costa Rica were 7 m (23 ft) and 11 and 17 em (4 and 7 in) in d.b.h. after 3 years (12). A 2-year-old planting in Colombia averaged 1.9 m (6.2 ft) in height and had 86 percent survival (3). After 7 years mean annual height growth was 2.6 to 2.9 m (8.5 to 9.5 ft) on sands and 2.0 to 2.2 m (6.6 to 7.2 ft) on heavier textured soils in Surinam (36).

Fertilizers have been unsuccessful in improving juvenile height or diameter growth (12). In one trial, several combinations of nitrogen, phosphorus, and potassium did not affect either height or diameter growth of laurel in Costa Rica. In another trial, growth of laurel seedlings 1 year after outplanting was not significantly different between unfertilized and fertilized plots of laurel alone or between fertilized and unfertilized plots with laurel planted with maize (5).

At least two laboratory observations have shown that light and temperature affect seedling growth (12), the best regime being a long (14.5 hr) day and high constant temperature, 30° C (86° F). Height growth occurs in periodic flushes during the growing season; when branches are elongating, terminal growth is slow. Cambial activity begins as the terminal initiates flushing. In Costa Rica, growth rings are almost always annual (32). However, boundaries between summer and early wood are not always distinct or abrupt so that several disks from different bole levels are usually needed to detect all growth rings.

Vegetative Reproduction- Coppicing and epicormic branching on injured young trees have been reported in Costa Rica (12). Sprouting was seer from lateral roots in Trinidad (21). But research in this particular area seems nonexistent except for us of stem and branch sets in laurel tree improvement work in Colombia (14,35).

Sapling and Pole Stages to Maturity

Growth and Yield- Mature laurel is a medium to large tree. Under optimum growing conditions it may reach 30.5 in (100 ft) and about 100 cm (36 in) in d.b.h. (12). More commonly, it is 20 in (66 ft) high and 46 cm (18 in) in d.b.h. The bole is cylindrical and erect, with whorled branches appearing in horizontal layers. There is good natural pruning for 50 to 60 percent of the bole, even in open-grown trees. Buttresses are small, extending from 0.9 to 3.0 in (3 to 10 ft) upwards from the ground.

The outer bark is greenish brown on young trees, becoming light gray or brown and slightly fissured at maturity. Inner bark is light brown, fibrous, and tasteless. It gives off a slight odor of garlic, a fact that promoted its scientific name (16). Although laurel is native to most of tropical America, it is not yet a major plantation species in the Western or Eastern Hemispheres. Thus, almost all growth records have been collected from trees growing in natural forests. In older, mature stands (more than 80 years), it is common to find only one individual per 2.0 hectares (4.9 acres). In younger stands (less than 30 years), where tolerant species have not yet had time to outgrow laurel, clumps of few to 30 or more individuals can be found over small distances. There are no reports on total longevity.

According to OFI experience with field provenance collections, the best stands of laurel are located on the Caribbean coast of Honduras, Nicaragua, and Costa Rica. The oldest natural stands of laurel for which growth data have been collected are found in the Atlantic lowlands of Costa Rica (12); recorded d.b.h. was 79, 89, and 91 cm (31, 35, and 36 in) for 40-, 50-, and 60-year-old trees. Mean annual growth for an average tree at 40 years was 0.19 in' (34 fbm, International 0.25-in Log Scale). A volume table with upper height and d.b.h. limits of 24 m (79 ft) and 76 cm (30 in) exists for laurel found in second-growth forest in Alajuela and Heredia Provinces in northern Costa Rica (22).

Laurel intercrops well with agricultural crops (40). In the coffee region of Chinchina, Colombia, at 1400 in (4,600 ft), in a planting with 100 to 200 laurel trees per hectare (40 to 80/acre), laurel could produce 49 to 74 m³/ha (700 to 1,057 ft³/acre) per year over a 20-year period (26). When intercropped with coffee in Costa Rica (41), laurel had a mean annual increment of 10.8 m³/ha (154 ft³/acre) in a 15-year-old planting.

Table 1- Height and d.b.h. of laurel (Cordia alliodora) in plantations at Los Diamantes and Turrialba, Costa Rica

Plantation location Age Total

Height Diameter

  (yr) (m) (ft) (cm) (in)
           
La Isla (5) 29.9 22 72.2 25.1 9.9
Los Diamantes (12) 24 29.3 96.1 37.8 14.9
Bajo Chino (slope) (5) 18.4 NA¹ NA 19.6 7.7
Bajo Chino (flat) (5) 18.4 NA NA 25.4 10
Bajo Chino (5) 17 NA NA 30.7 12.1
Old Arboretum (12) 13 13.2 43.3 16.6 6.5
Old Arboretum (12) 13 19.6 64.3 22.2 8.7
Florencia Norte (5) 12.8 NA NA 18.6 7.3
Old Arboretum (12) 10 13.4 44 21 8.3

¹Not available.

Pure plantations of laurel were established as early as 1922 in Nigeria (30). Quantitative growth data are available only from Costa Rica, Puerto Rico, and Surinam. Through age 20 in Costa Rica (table 1), mean annual height and d.b.h. increments were slightly better than 1.0 m (3.3 ft) and 15 mm (0.6 in). Afterwards, growth seemed to decline somewhat. Extrapolating from 7-year data in Surinam, laurel could obtain a minimum outside bark d.b.h. of about 40 cm. (16 in) in 25 years (36). Projected d.b.h. growth is 40 to 50 cm (16 to 20 in) at 20 years for plantation sites in Colombia (29). In Puerto Rico's young plantations (table 2), height and d.b.h. were better in Subtropical Moist Forests and Subtropical Wet Forests than in Subtropical Dry Forests. But height growth on steep slopes was poorer than height growth on uniform or lower slopes in Subtropical Wet Forests.

Table 2- Height and d.b.h. of laurel (Cordia alliodora) on different sites in Pureto Rico

Location Age Height   Diameter   Life zone / Solis / Slope

  (yr) (m) (ft) (cm) (in)  
Catalina nursery 10 17 55.8 11.9 4.7 Subtropical Wet, Ultisol, gentle
Luquillo Biosphere Reserve (38)            
Tract 105 (19) 6 6.7 22 7.1 2.8 Subtropical Moist, Inceptisol, steep
Luquillo Biosphere Reserve 8 7.6 24.9 8.9 3.5 Subtropical Moist, Ultisol, moderate
Toro Negro State Forest (19) 8 4.6 15.1 NA¹ NA Subtropical Wet, Inceptisol, steep
Carite State Forest (20) 9 10.7 35.1 12.7 5 Subtropical Wet, Ultisol, gentle
Guilarte State Forest (20) 6 3.6 11.8 2.4 0.9 Subtropical Wet, Ultisol, lower slope
Guánica State Forest (20) 10 5 16.4 9 3.5 Subtropical Dry, Alluvium, valley floor

¹Not Available

Site variation affects laurel growth. In Costa Rica growth was poor on shallow stony soils and on a steep slope having less profile development than an adjacent flat area (5). In Surinam, best diameter growth on sandy soils was on the lower slopes where lower horizons had accumulated sufficient alluvial clay to retain soil moisture during long dry periods (36). On heavier textured soils best growth was also on the lower slopes; texture of the A horizon was lighter (loamy sand) and internal drainage was better there than on the ridge tops where drainage was poor because of plinthite accumulations (36). Observations from Puerto Rico and elsewhere indicate that growth in plantations slows, perhaps considerably, before sawtimber size is reached.

Rooting Habit- No active research on root development is known. Rooting has been reported as deep and extensive in Fiji (30) and large and spreading with surface laterals and sometimes a deep taproot in Puerto Rico (39). In both countries laurel has suffered little blowdown or stem breakage in the crowns during cyclonic storms.

Reaction to Competition- Silvicultural research of laurel is still in its infancy. Advances are being made as more countries recognize the value of laurel wood products and the species' potential for fast growth. Any silvicultural technique must consider that laurel is classed as an intolerant pioneer species, demanding lots of light for best growth.

Attempts have been made with limited success to encourage natural regeneration in Costa Rica by mechanically clearing or poisoning undesirable species on selected sites (5). Considerable time and money are needed, however, to keep down weeds or more tolerant shrubs and trees once natural seeding has been established. Other artificial regeneration systems are line and enrichment plantings (12). In line plantings, swaths are cleared through natural forest and laurel seedlings or stump plants are planted at specified spacing up and down the lines. Shade from adjacent forests doesn't seem to reduce growth of C. trichotoma in Argentina (6).

In Surinam, enrichment plantings have been done in two ways (36). In the first, commercial natural forest species are removed and all undesirable plants are poisoned or cut 1 to 2 years before the anticipated planting date. Laurel seedlings are then planted in clumps of three, 1 m (3.3 ft) apart so that each seedling is the apex of an equilateral triangle. Spacing between clumps is 10 by 5 m (33 by 16 ft), or 200 groups per hectare (81/acre). At the final rotation some 130 to 150 trees per hectare (53 to 61/acre) remain. Any laurel natural regeneration is left at planting time.

In the second method used in Surinam, all commercial species with diameters from 20 to 40 cm (8 to 16 in) are left after initial logging of 12.5/ha (30.9/acre) blocks. Rows 250 m (820 ft) long spaced 1.5 m (5 ft) apart are then established in an east-west orientation; planting holes are dug for laurel seedlings at 10 m (33 ft) intervals along the lines. Weeding of seedlings is done by machetes or poisoning. The first thinning is done after 3 years, and the best tree in each group is left.

As early as 1945 in Puerto Rico and 1963 in Costa Rica, laurel was successfully established through the Taungya Method in which tree seedlings are planted between rows of food crops; when crops are harvested the tree seedlings are left in place (1). There are several agroforestry systems under study in Costa Rica now to determine whether laurel can be grown successfully in associations with various cultivated crops (5). Some field observations show that laurel grows better when secondary forest brush is allowed to form the understory than when grass predominates, as occurs in repeatedly cleaned plots (12). The grass may offer greater root competition to laurel trees than the other secondary shrubs.

Damaging Agents- Rodents and birds destroy much of the seed in forest clearings or on direct seeded areas where seeds are not protected or covered (31). Coleoptera of the genus Amblycerus also damage laurel seeds (12). In the nursery, seedlings have been infected by a leaf-spot disease in Puerto Rico and by root cutters (Phyllophaga spp.) in Venezuela (12). The terminal of outplanted seedlings is very susceptible to damage or malformation from competing weeds and vines (25).

More than 212 different forms of insects were found on laurel in Panama. But none of the seedlings or trees affected showed any signs of serious injury (12). In Puerto Rico laurel foliage has been heavily attacked by the Spanish elm lacewing bug, Dictyla montropidia (20). A canker-causing rust, Puccinia cordiae, attacks laurel in the West Indies and has been reported in Guatemala (12). Cankers form at the base of young lateral branches and are sources for usually more serious secondary infections. Trees planted on wet sites are very susceptible. In the Solomon Islands, a black fungal or viral canker (unknown spp.) has caused severe damage to nodes on main stems (30). There may be some relationship between this disease and the fact that these island., are continually humid, with no distinct dry season Mistletoes (Loranthaceae) are also a problem in some areas (12). At least one grass, Melinis minutiflora, has had an adverse effect on laurel growth when extracts from the grass were applied on young seedlings (12). Ant domitia are common in the swollen nodes of laurel lateral branches. They are most prominent in Central America and northwestern South America being almost totally absent from the West Indies Ants usually cause no damage to laurel plantings.

Special Uses

Throughout its range, laurel is also used as a shade tree in coffee and cacao plantations as well as in pastures. Humans eat fruits in some places and both seeds and leaves are used for home medicinal purposes (15). Laurel is suitable for ornamental use in urban residential areas and has been tried for use in honey production because of its copious flowering (16). In Brazil it Yielded 266 liters (70 gal) of ethanol per ton of dry material; this compares well with a yield of 325 liters (86 gal) per ton produced by Protium spp., the best of 25 species tested (28).

Laurel is still to be evaluated fully for pulping; physical and mechanical properties of sawn and roundwood are quite good. General strength properties are good and similar to those of mahogany (4,9,34). Specific gravity ranges from 0.44 to 0.52 (10). Freshly felled material seasons rapidly with only slight warping and checking; volumetric shrinkage is around 9 percent. Wood is easy to work, finishes smoothly, and glues readily (18). Heartwood is not receptive to preservative treatments but has some resistance to fungi, termites, and marine borers (4). Degree of resistance appears to be related to coloring of the heartwood, darker colored wood being more resistant than lighter colored heartwood. Heartwood coloring is also used to distinguish between laurel blanco (light) and laurel negro (dark) wood in Central America (27). The former is associated with the soft-wooded Cordias, like C. alliodora; the latter is associated with the harder, heavier density (specific gravity 0.63 to 0.84) Cordias like C. gerascanthus (4). Variations in heartwood coloring within any of two major groups could be caused by local site properties as well as by age (27).

Genetics

Considerable confusion still exists as to the taxonomy of laurel. Great variation in climate, soils, and elevation within its extensive natural range contribute to large differences in flowering and fruiting phenology and morphological features such as flower and leaf size (30). Thus Cordia alliodora has several botanical synonyms. The most common are Cerdana alliodora and Cordia gerascanthus. There is some doubt whether Cordia trichotoma, growing in Brazil and Argentina, is really a separate species or merely a variety of C. alliodora (30).

Two distinct races are recognized in Costa Rica and probably exist throughout the extensive native range which includes wet and dry habitats (12). Laurel was included in the 1977 FAO Panel of Experts Report on Forest Genetic Resources Priorities for Mexico, the Caribbean, and Central and South America (8). The species is not in danger of disappearing because of its large range, but there are areas, such as in Colombia, where overcutting may destroy local populations. For this reason and the fact that the species exhibits fast growth in plantations and has utility for various wood products, there is an urgent need for botanical, genecological, and collecting work.

The most vigorous collection program for provenance testing now underway is that coordinated by the OFI. Since 1977, 19 native and 2 exotic collections have been made, within altitudinal ranges of 50 to 2000 m (160 to 6,600 ft) and precipitation ranges of 1040 to 4700 mm (41 to 185 in). Most results have been analyzed for trials only 1 year old. Definite trends are not yet possible to interpret but the Finca la Pineda, Nicaragua, seed source has consistently performed well, as have the Finca la Fortuna and San Francisco sources from the north coast of Honduras. Sources from Costa Rica have usually given rather poor nursery results but surviving trees have performed well in the field (30). A separate collection of 24 Costa Rican plus-trees did poorly in Puerto Rico from 1976 to 1978 and the test was closed after 2 years (42). Tree improvement work is also underway with laurel in Colombia; 31 superior trees were selected in 1978 (35). Seed collection areas have also been designated in Costa Rica and Colombia (29). As the OFI-coordinated trials develop and more data are analyzed, interesting trends should become discernible as to adaptation of laurel provenances to particular soil, climate, and altitudinal regions.

Literature Cited

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