Annual ring in nine tree species in a Neotropical Island with high
precipitation: Coco Island, Costa Rica
Coco Island is of volcanic origin with an area of 24 km2, located 530 km
from the Pacific coast of Costa Rica and is the furthest Costa Rican
Island from the continent and with a rainfall of over 7000 mm years-1.
Two types of forest are present, low elevation humid forest and high
elevation cloud forest. This study aims to establish different
distinctiveness of annual rings and dendrochronological potential (DP)
of nine tree species. Any annual ring boundary were not observed in C.
pettieri and H. fascicularis; therefore, they did not present any DP.
Annual ring type 1 (density variation) was presented in A. compressa, H.
succosa, H. odorata, and P. cocosensis, however the annual rings
boundary was more defined in A. compressa and H. succosa than other
species. O. insularis and S. Holdridgei presented annual rings boundary
type 5, fiber band and were adequate distinctiveness. Finally, Eugenia
pacifica presented annual ring type 3 (pattern de fiber/parenchyma) and
type 4 (vessels distribution), but its distinctiveness was limited. Coco
Island´s trees presented seven species with more or less distinctive of
annual ring, but three species (A. compressa, E. pacifica, and P.
cocosensis) presented low DP. Meanwhile H. succosa, H. odorata, O.
insulares, and S. holdridgei showed medium DP. These species growth in
the two types of forest in the island and add to abundance and tree
diameter, these species have some DP and they can be used to establish a
chronology from 50 to 130 years.