Native and Non-Native Species in Urban Tropical Forests of San Juan, Puerto Rico

Introduction

Field sites are located the Rio Piedras watershed in Puerto Rico. Forest fragments span the watershed from the low-elevation urban core on the coast, to suburban areas in the upper watershed. The Rio Piedras watershed is in the subtropical moist forest life zone, ranges in elevation from 0-220 meters above sea level, has mean annual precipitation of 1750 mm, and mean annual temperature of 25.7º C. Soils are predominantly Utisols derived from volcanistic materials. Forests are all secondary regeneration following widespread agricultural abandonment in Puerto Rico starting in the 1930s. Site histories range from US military housing and coffee plantations. The Rio Piedras is a secondary forest containing a mixture of native and non-native species. 

Native Species

Guatteria caribaea
Family: Annonaceae




Ocotea leucoxylon
Family: Lauraceae
Common name: Loblolly Sweetwood



Flower color: Yellow
Fruit/Seed Color: Black
Bloom Period: Late Spring
Height (Mature in feet): 70
Nitrogen fixation: No

Native to Puerto Rico, it is a very species in montane tropical forests. The Ocotea leucoxylon community is found in a small number of patchy remnants in a primarily distirubed landscape dominated by active and abandoned agricultural areas and development. This species deserves consideration for landscape elements in need of continued conservation.

Ocotea sintenisii
Family: Lauraceae



Calophyllum calaba
Family: Clusiaceae (Guttiferae)
Common Name: Santa-Maria/False-Mamey



Flower color: Orange
Fruit/Seed Color: Brown
Bloom Period: Late Spring
Height (Mature in feet): 65
Nitrogen fixation: No

Calophyllum calaba is frequently used for reforestation because it is easily established by direct seeding and grows well in almost all soils. However, its growth is generally slow. The Santa-Maria often forms a dense crown with small fragrant flowers, which make it a popular shade tree or protective hedges. The wood is used widely in the tropics where a strong, moderately durable timber and general utility wood is needed.

Members of the Clusiaceae family sometimes provide pollinators with rewards other than pollen or nectar; specifically, some species offer resin which bees can use in nest construction. This trait is rarely found in other families.

Sloanea berteriana
Family: Elaeocarpaceae



Casearia arborea
Family: Flacourtiaceae



Casearia decandra
Family: Flacourtiaceae
Common name: tostado



Flower color: Greenish-white
Fruit/Seed Color: Brown
Bloom Period: Spring
Height (Mature in feet): 20
Nitrogen fixation: No

Casearia decandra is sometimes employed as a honey plant. It is an evergreen plant with simple ovate leaves, arranged opposite. The flowers are five-petaled and arranged in panicles. It often grows in disturbed areas, forest openings, very rocky sites, and the understories of lower density forests. Casearia decandra often functions as a gap-filled species. It can survive several decades in fertile sites with sufficient sunlight. The stems of tostado are sometimes used as fuel and fenceposts and acts as an important honey plant. The species furnished food and cover for wildflire, contributes to biodiversity, and helps stabilize the soil.

Homalium racemosum
Family: Flacourtiaceae



Samyda spinulosa
Family: Flacourtiaceae



Chrysophyllum argenteum
Family: Sapotaceae



Hirtella rugosa
Family: Chrysobalanaceae



Andira inermis
Family: Fabaceae



Inga laurina
Family: Fabaceae



Eugenia monticola
Family: Myrtaceae



Miconia impetiolaris
Family: Melastomataceae



Miconia prasina
Family: Melastomataceae
Common name: Camasey blanco/Granadillo bobo

Flower color: White
Fruit/Seed Color: Blue/Brown
Bloom Period: Spring
Height (Mature in feet): 20
Nitrogen fixation: No

Miconia prasina often grows in disturbed areas. The wood is used for fuel and occassionally as tool handles. Miconia prasina often acts as a transitional (successional) species between pasture, farmland, or disturbed forest and secondary forests.

Miconia racemosa
Family: Melastomaceae



Rourea surinamensis
Family: Connaraceae



Comocladia glabra
Family: Anacardiaceae



Guarea guidonia
Family: Meliaceae
Common name: American muskwood

Flower color: White
Fruit/Seed Color: Green
Bloom Period: Spring
Height (Mature in feet): 10
Nitrogen fixation: No

Guarea guidonea is an important species for wood, construction, and agricultural implements. It was considered the best wood for furniture. The wood is strong and works in machines easily. It has many uses: furniture, interior molding, general construction and carpentry. It was recommended as a ornamental shade tree. At the present time, it is one of the most common shade trees. The leaves and flowers are sometimes used for medicinal purposes.

Schefflera morototoni
Family: Araliaceae



Cordia borinquensis
Family: Boraginaceae



Tabebuia heterophylla
Family: Bignoniaceae
Common name: Pink Trumpet Tree

Flower color: White
Fruit/Seed Color: Green
Bloom Period: Spring
Height (Mature in feet): 60
Nitrogen fixation: No

The pink trumpet tree is well suited for use as a street tree or for other areas such as in parking lots and buffer strips where temperatures are high and soil space is limited. They will create a canopy over a sidewalk when planted and develop high, arching branches several years after plants. The tree will provide lasting shade plus the added benefit of a sensational season color show.

Gonzalagunia spicata
Family: Rubiaceae



Psychotria berteriana
Family: Rubiaceae



Coccothrinax barbadensis
Family: Arecaceae



Prestoea montana
Family: Arecaceae



Roystonea borinquena
Family: Arecaceae
Common name: Royal palm



Flower color: Yellow
Fruit/Seed Color: Green
Bloom Period: Winter
Height (Mature in feet): 50
Nitrogen fixation: No

Royal palms are popular ornamental trees due to their striking appearanace and are extensively planted in Puerto Rico for this purpose. It has a high tolerance for growing in a variety of soil types and has roots that do not damage sidewalks, which makes it highly usable for landscaping and street planting. Its timber is occasionally used for construction but is susceptible to termite attach. The fruits are fed to pigs and other livestock and the flowers are visited by honey bees.

Native in Danger of Extinction 

Ternstroemia stahlii

Family: Theaceae

Lyonia rubigenosa var. stahlii

Family: Ericaceae

Senna pendula

Family: Fabaceae

Stahlia monosperma

Family: Fabaceae

Eugenia stahlii

Family: Myrtaceae

Argythamnia stahlii

Family: Euphorbiaceae

Endemic

Magnolia portoricensis
Family: Magnoliaceae



Magnolia splendens
Family: Magnoliaceae



Pleodendron macranthum

Family: Canellaceae



Licaria brittoniana
Family: Lauraceae

Harrisia portoricensis

Family: Cactaceae

Clusia gundlachii

Family: Clusiaceae (Guttiferae)



Marcgravia sintenisii
Family: Marcgraviaceae



Thespesia grandiflora
Family: Malvaceae



Ficus stahlii
Family: Moraceae

Banara portoricensis

Family: Flacourtiaceae

Begonia decandra

Family: Begoniaceae

Lyonia truncata var. proctorii

Family: Ericaceae

Diospyros sintenisii

Family: Ebenaceae

Calliandra locoensis

Family: Fabaceae

Neorudolphia volubilis

Family: Fabaceae

Poitea florida

Family: Fabaceae



Calyphtranthes acevedo
Family: Myrtaceae



Calyptranthes estremera
Family: Myrtaceae



Calyptranthes luqillensis
Family: Myrtaceae



Eugenia eggersii
Family: Myrtaceae



Eugenia haematocarpa
Family: Myrtaceae



Eugenia padronii
Family: Myrtaceae



Eugenia stewardsonii
Family: Myrtaceae



Henriettea membranifolia
Family: Melastomataceae



Heterotrichum cymosum
Family: Melastomataceae



Sagraea portoricensis
Family: Melastomataceae



Dendropemon bicolor
Family: Loranthaceae

Maytenus ponceana

Family: Celastraceae



Ottoschulzia rhodoxylon
Family: Icacinaceae

Ilex cookii

Family: Aquifoliaceae

Ilex sintenisii

Family: Aquifoliaceae

Boxus portoricensis

Family: Buxaceae

Acalypha bisetosa

Family: Euphorciaceae

Acalypha portoricensis

Family: Euphorbiaceae

Hyeronima clusioides

Family: Euphorbiaceae



Trichilia triacantha
Family: Meliaceae



Heteropteris wydleriana
Family: Malpighiaceae



Stigmaphyllon floribundum
Family: Malpighiaceae

Dendropanax laurifolius

Family: Araliaceae

Schefflera gleasonii

Family: Araliaceae

Forsteronia portoricensis

Family: Apocynaceae

Tabernaemontana oppositifolia

Family: Apocynaceae

Marsdenia elliptica

Family: Asclepiadaceae

Matelea borinquensis

Family: Asclepiadaceae

Matelea sintenisii

Family: Asclepiadaceae

Matelea variifolia

Family: Asclepiadaceae

Cordia bellonis

Family: Boraginaceae

Cordia wagneriorum

Family: Boraginaceae

Gesneria citrina

Family: Gesneriaceae

Gesneria cuneifolia

Family: Gesneriaceae

Gesneria pedunculosa

Family: Gesneriaceae

Crescentia portoricensis

Family: Bignoniaceae

Tabebuia haemantha

Family: Bignoniaceae

Lobelia assurgens var. portoricensis

Family: Campanulaceae

Chromolaena borinquensis

Family: Asteraceae

Critonia portoricensis

Family: Asteraceae

Koanophyllon dolicholepis

Family: Asteraceae

Koanophyllon polyodon

Family: Asteraceae

Mikania odoratissima

Family: Asteraceae

Mikania porosa

Family: Asteraceae

Vermonia proctorii

Family: Asteraceae

Eleocharis sintenisii

Family: Cyperaceae

Hohenbergia antillana

Family: Bromeliaceae

Non-native Species

Artocarpus altilis
Family: Moraceae



Ardisia elliptica
Family: Myrsinaceae



Albizia procera
Family: Fabaceae
Common name: White siris/Tall albizia

Flower color: Greenish-yellow
Fruit/Seed Color: Brown pods
Bloom Period: Summer
Height (Mature in feet): 80
Nitrogen fixation: Yes

This species provides wood for a variety of purposes, nutritious fodder for livestock and shade for tea plantations. Like many nitrogen fixing trees, white siris survives on a variety of soils. Its ability to grow on dry, sandy, stony, and shallow soils makes it a useful species for reforestation of difficult sites. Food survival and rapid early growth have been reported. In Puerto Rico, white siris is an aggressive pioneer, forming pure stands on abandoned farms and other disturbed sites. The native range is South and Southeast Asia.

Adenanthera pavonina
Family: Fabaceae
Common name: Saga Tree

Flower color: Yellow
Fruit/Seed Color: Dark Brown
Bloom Period: Spring
Height (Mature in feet): 50
Nitrogen fixation:Yes

The tree has been planted extensively throughout the tropics as an ornamental and has become naturalized in many countries. It is an important tree in Southeast Asia and the Pacific Islands. Cultivated in home gardens and often protected in forest clearings and village common areas, this useful tree provides quality fuelwood, wood for furniture, food, and shade for economic crops like coffee and spices. There are historical accounts from Southeast Asia and Africa of using all parts of the tree for traditional medicines.

Syzygium jambos
Family: Myrtaceae



Terminalia catappa
Family: Combretaceae



Spathodea campanulata
Family: Bignoniaceae
Common name: African Tuliptree

Flower color: Orange
Fruit/Seed Color: Brown
Bloom Period: Spring
Height (Mature in feet): 80
Nitrogen fixation: No

Termed as one of the "world's most spectacular flowering trees." The African Tuliptree comes from the rainforests of Equatorial Africa. It is widely planted throughout the tropics and has naturalized in many parts of the Pacific.In many places, the African Tuliptree invades both abandoned farmland and mature forests, where the seeds germinate rapidly and form understory thickets from which a few saplings eventually grow into the canopy.