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The Canada plot was established in November 1985 at the OTS La Selva Biological Station in Puerto Viejo de Sarapiqui, Heredia, Costa Rica, specifically at La Guara Annex. The plantation was located on a level abandoned pasture site at 60 m elevation that was occupied by grasses, guava (Psidium guajaba) and lime (Citrus spp.) trees. Soils (Fluventic dystropept) are characterized by low pH (4.6) with a base saturation less than 30% and low cation exchange capacity (Sancho and Mata 1987). The site was prepared by clearing trees, shrubs, and grasses with machetes and then burned. No herbicides or fertilizers were used; periodic cleaning by machete was done as needed. Seeds were collected from selected and marked trees for this purpose inside and outside the La Selva Biological Station. The seeds were collected directly from the soil, where they usually fall when ripe. However, when the seed is wind dispersed or preyed upon by birds and animals, it must necessarily be collected from the tree. Seeds were always collected from at least three trees and preferably up to ten trees were used. Once the seeds were collected, they were mixed, and seedlings raised in a Direccion General Forestal.

Seeds were germinated in trays containing washed river sand, no pregerminative treatments were performed. Seedlings were transplanted soon after germination to plastic bags (12 cm wide and 22 cm long) filled with a mixture of nonsterilized alluvial and Ultisol soil. Bags were shaded for a few weeks after transplanting and then the seedlings grew under full sun conditions. Seedlings averaged 0.35 m in height at time of out-planting and were carried to the field in plastic bags. Two exceptions are Cordia alliodora and Terminalia ivorensis, which were produced as stumplings (decapitated seedlings from bare root stock). When local seeds were not available, seedlings were purchased from commercial nurseries. Three of the original species failed and were subsequently replaced by Vitex cooperi, Terminalia ivorensis and Hyeronima alchorneoides six months later. Seedling production methods and seed sources are typical of the material available to farmers in the region. Timber species currently used in local sawmills or species that had little silvicultural information were chosen for testing. Fourteen species (12 native and two exotic) were planted in a randomized complete block design with five replications per block. Plots of 49 (7 x 7) trees were planted at 2 m spacing with the inside 25 (5 x 5) trees measured annually.

Measurements of Diameter Breast Height (DBH) (mm) and height (dm) were taken starting in December of 1986, and were collected every six months until December of 1992. Every round of measurements is referred to as an “ALT” in the dataset and the measurements taken include Diameter Breast Height (DBH) (mm) and height (dm). The final dataset includes 13 rounds of measurements (13 ALTs) and the seventh, ninth, and eleventh rounds of measurements (ALT7, ALT9, ALT11) are missing from the final dataset. Therefore, after the sixth round of measurements were recorded in December of 1988, the dataset includes annual measurements from 1988 and 1992.