PREVIOUS WORK 



Prepariiitr tliis book has called for full use of 

 the previous work of botauists and foresters and 

 also for additional field investifjation. Puerto 

 Rico and the Virgin Islands, discovered by Colum- 

 bus, settled early, and both small and accessible, 

 were amonp the firet areas of tropical America to 

 become well explored botanically. Principal pub- 

 lications on the plants of these islands are listed in 

 the bibliographies by Britton and Wilson (5) 

 and Otero, Toro, and" Pagan (32), the latter con- 

 taining also a historical sunnnary. 



The most valuable reference consulted is the de- 

 scriptive flora of Puerto Rico and the A'irgin Is- 

 lancls by Britton and AVilson (5), published in 

 English in 1923-30. Earlier, in 1903-11, Urban 

 (37) wrote a flora of Puerto Rico in Latin and 

 German. In 1883-88 there was published in 

 Puerto Rico an incomplete flora in Spanish by 

 Stahl (.:J.5), afterwards reprinted in 1936-37. Th'e 

 Virgin Islands have been the subject of other 

 floras, the earliest by Hans West in 1793. Another 

 flora of the Virgin Islands by Eggers {8<i) ap- 

 peared in 1879. Britton (4) publis^ied a flora of 

 the United States Virgin Islands in 1918, a year 

 after their purchase from Demnark. 



Nearly a century ago, Jose Maria Fernandez (9, 

 pp. 181-215) compiled a list of trees of Puerto 

 Rico in his "Tratado de la Arboricultura Cubana," 

 published in Havana in 1867. Entitled "Arbolado 

 de Puerto-Rico," this annotated list contained 

 about 175 trees arranged by Spanish common 

 names with scientific names for about 100. Intro- 

 duced, as well as native, species and several shrubs 

 were mentioned. There were notes on size, occur- 

 rence, wood including specific gravity, and uses 

 and also lists for special purposes. 



Shortly after Puerto Rico became a part of the 

 United States in 1898, studies of the forests began 

 with a report by Hill (13) in 1899 which described 

 16 important timbers. In 1903 the Luquillo Di- 

 vision of the Caribbean National Forest, now the 

 Luquillo Experimental Forest, was established 

 from former Spanish crown lands by proclama- 

 tion of President Theodore Roosevelt. A prelim- 

 inary list of trees of the Luquillo region w<as pre- 

 pared soon afterwards by Gilford (JO). Murphy 

 (29), of the United States Forest Service, pub- 

 lished a list of 292 tree species of Puerto Rico be- 

 longing to 172 genera and 57 families, with notes 

 on size, distribution, wood, and uses by W. D. 

 Brush, Louis S. Murphy, and C. D. Mell. Hold- 

 ridge and Munoz (16) described and illustrated 

 seven poisonous trees in an article on the poisonous 

 plants of Puerto Rico. In his manual on propaga- 

 tion of trees and establishment of forest planta- 

 tions, Gilormini (11) inserted a list of native and 

 exotic trees and shrubs of Puerto Rico with both 

 Spanish and scientific names. 



Much information about forest trees of Puerto 

 Rico and the Virgin Islands is contained in articles 



in The Caribbean Forester and other publications 

 by the Institute of Tropical Forestry. Longwood 

 (2'2, 23), of the United States Forest Service, made 

 a special investigation of the woods of Puerto Rico 

 and the Caribbean region, including about 70 spe- 

 cies in this book. 



The agricultural experiment stations in Puerto 

 Rico and the Virgin Islands have made additional 

 studies of trees. Wolcott (^0) tested the resistance 

 of woods to attack by dry-wood termites. Winters 

 and Almeyda (39) reported on the ornamental 

 trees of Puerto Rico. Kennard and Wintere (18) 

 described and illustrated the common fruit trees in 

 their publication on fruits and nuts. Poisonous 

 plants of the United States Virgin Islands, sev- 

 eral being trees, were described and figured by 

 Oakes and Butcher (30). 



Other important references are mentioned below 

 and listed under Literature Cited. Additional 

 botanical floras and tree publications of various 

 tropical countries, as well as taxononiic mono- 

 graphs, have provided useful information for this 

 book. 



PREPARATION OF THIS BOOK 



Preparation of an illustrated popular reference 

 on the trees of Puerto Rico was one of the first 

 ]irojects undertaken when, in 1939, the United 

 States Forest Service began forest research in 

 Puerto Rico with the establishment of the Tropical 

 Forest Experiment Station, now Institute of Trop- 

 ical Forestry, in Rio Piedras. Leslie R. Hold- 

 ridge, who was in cha.rge of the project until the 

 end of 1941, made Ijotanical collections of Puerto 

 Rican trees and supervised the preparation of a 

 few hundred drawings. He wrote two prelimi- 

 nary volumes of "Trees of Puerto Rico" (lli, 15), 

 published in 1942 in both English and Spanish, 

 each volume containing drawings and descriptions 

 of 50 tree species. These small editions were soon 

 exhausted. It was intended to issue additional 

 parts covering a total of about 600 native and ex- 

 otic tree species to be followed by a revision printed 

 in a single volume. However, further work was 

 suspended during the war. Identifications of sev- 

 eral luindred tree specimens collected mostly by 

 Holdridge and Luis E. Gregory were made by the 

 New York Botanical Garden. These specimens 

 were the beginning of the Institute's herbarium. 



The present project on the trees of Puerto Rico 

 and the Virgin Islands was begun by the authors 

 together in 1950. The junior author had assisted in 

 the earlier project upon his arrival in Puerto Rico 

 in 1942, while the senior author did some reference 

 work in 1941. The ai'ea was expanded to include 

 the nearby smaller Virgin Islands, both United 

 States and British, which have fewer tree species 

 and very few additions. 



The senior author as dendrologist made field 

 trips in Puerto Rico in 1950, 1952, 1954, and 1955. 

 The botanical descriptions were prepared mostly 



