Area of 1,840 acres. This National Forest with 

 a remnant of natural vegetation originated in a 

 forest reserve formerly under the Spanish 

 crown. 



The rare and endemic trees of Puerto Rico 

 and the Virgin Islands will be the subject of 

 another report in this series and have been de- 

 scribed in the 2-volume illustrated reference on 

 the trees of these islands (Little and Wads- 

 worth 1964; Little, Woodbury, and Wadsworth 

 1974, p. 15-19, iv-xiv). Lists of the endemic 

 trees and other trees of the Caribbean National 

 Forest have been prepared (Little 1970b, Little 

 and Woodbury 1976) . 



Within the Caribbean National Forest are 225 

 species of native trees, more than in any other 

 equal area of the United States. The number is 

 about two-fifths of the 547 species of trees na- 

 tive in Puerto Rico and the Virgin Islands. Of 

 the 142 tree species endemic or confined to these 

 islands, 68, or nearly one-half, grow wild within 

 this National Forest. In addition, this National 

 Forest has 22 of about 100 other tree species 

 native beyond Puerto Rico and the Virgin Is- 

 lands that are classed as rare within these 

 islands. 



Thus, 90, or two-fifths, of the 225 tree spe- 

 cies native within the Caribbean National For- 

 est are classed as endemic or rare. None of the 

 90 grows wild within continental United States. 

 Most are not closely related to the temperate 

 species listed for the other National Forests. 

 Some belong to unfamiliar plant families char- 

 acteristic of the tropics. 



The 90 species of endemic and rare trees of 

 the Caribbean National Forest may be grouped 

 into three lists, as follows : 



1. Trees endemic to Luquillo Mountains, 23 

 species (including 9 also in nearby Carite Com- 

 monwealth Forest) . 



2. Other trees endemic to Puerto Rico, 45 

 species (including 2 also in Vieques and 1 of 

 these in St. Croix) . 



3. Trees rare in Puerto Rico but native be- 

 yond, 22 species. 



The extent of this valuable living collection 

 of endemic and rare trees is best shown by pub- 

 lication of the lists, as under the other National 

 Forests. In the three lists the species with sci- 

 entific and common names are numbered in bo- 

 tanical order as in the 2-volume reference cited 

 above. Numbers 1-250 are in the first volume 

 and 251-750 in the second. Several endemic or 

 local species are designated as not rare, being 

 common locally. A few have slightly broader 

 range, as mentioned. Brief notes on rarity have 

 been added. 



1. Trees Endemic to Luquillo Mountains 



The list of 23 tree species endemic to Carib- 

 bean National Forest and Luquillo Mountains 

 includes 9 which range also slightly beyond into 

 nearby Carite Commonwealth Forest. Most of 

 the 14 confined to the Luquillo Mountains have 

 their entire natural range within the Caribbean 

 National Forest. Thus, the Forest Service has 

 sole responsibility for management and protec- 

 tion, so that these species will not become en- 

 dangered or extinct. 



35. Magnolia splendens Urban, laurel sabino 

 (not rare) 



120. Croton poecilanthus Urban, sabinon 

 (not rare) 



160. Laplacea portoricensis (Krug & Urban) 

 Dyer, maricao verde 



212. Micropholis garciniifolia Pierre, caimi- 

 tillo verde (not rare; also Carite) 



237. Tabebuia rigida Urban, roble de sierra 

 (not rare) 



239. Antirhea obtusifolia Urban, quina (not 

 rare; also Carite) 



284. Myrica holdridgeana Lundell, palo de cera 



401. Ravenia urbanii Engler, tortugo prieto 

 (also Carite) 



465. Ilex sintenisii (Urban) Britton (not 

 rare; also Sierra de Naguabo) 



512. Ternstroemia heptasepala Krug & Urban 



513. Ternstroemia luquillensis Krug & Urban 

 536. Xylosma schwaneckeanum (Krug & Ur- 

 ban) Urban (also Carite) 



553. Calyptranthes luquillensis Alain 



564. Eugenia boHnquensis Britton, guaya- 



bota de sierra (not rare; also Carite) 



570. Eugenia haematocarpa Alain, uvillo 

 589. Marlierea sintenisii Kiaersk, beruquillo 

 600. Miconia foveolata Cogn., camasey 

 621. Tetrazygia urbanii Cogn., camasey (also 



Carite) 



632. Ardisia hiquillensis (Britton) Alain, 

 mameyuelo (also Carite) 



633. Grammadenia sintenisii (Urban) Mez 

 650. Styrax portoricensis Krug & Urban, 



palo de jazmin (also Carite) 



689. Brunfelsia lactea Krug & Urban, vega 

 blanca (also Carite and Monte Torito near 

 Cayey) 



690. Brunfelsia portoricensis Krug & Urban 



2. Other Trees Endemic to Puerto Rico 



This list contains 45 tree species of the Car- 

 ibbean National Forest endemic to Puerto Rico 

 but not confined to this National Forest. Many 



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