1. The Littoral Zone
  2. The Dry Lowland Zone
  3. The Transition Zone
  4. The Moist Zone
  5. The Fern-Sedge Zone

The Littoral Zone has mangrove forests in the outer reaches, plant communities on beach sand and dunes, and herbaceous plant communities on the coastal slopes to the back which are hit by salty sea winds.

Mangrove

There are four kinds of mangroves: red mangrove (Rhizophora mangle)(769, 95, 97), white mangrove (Laguncularia racemosa) (119), black mangrove (Avicennia germinans) (117, 118), and button mangrove (Conocarpus erectus) (120). Seaside hibiscus (Hibiscus tiliaceus) grows behind the mangroves (121).

Rhizophora mangle
  No.769 No.95 No.97
Laguncularia racemosa
  No.119
Avicennia germinans
  No.117 No.118
Conocarpus erectus
  No.120
Hibiscus tiliaceus
  No.121

Plant communities on beach sand and dunes

Plant communities on beach sand and dunes (771) are arranged from the beach front toward inland as follows Galapagos beach amaranthus (Amaranthus sclerantoides), an annual plant (204), beach dropseed (Sporobolus virginicus) (88), beach morning-glory (Ipomoea pes-capae) (103), inkberry (Scaevola pulmierii) on the crest of sand dunes (105), and saltbush (Cryptocarpus pyriformis) behind the dunes (182).

Plant communities on beach sand and dunes Amaranthus sclerantoides
  No.771   No.204
Sporobolus virginicus Ipomoea pes-capae
  No.88 No.103
Scaevola pulmierii Cryptocarpus pyriformis
  No.105 No.182

Herbaceous communities

On the coastal slope (131) grow communities of Galapagos carpetweed (Sesuvium edmonstonei) (107, 114) and Galapagos purslane (Portulaca howellii) (109, 111). Saltbush communities grow behind them (182).°°°°

the coastal slope grow communities
  No131
Sesuvium edmonstonei
  No.107 No.114
Portulaca howellii
  No.109 No.111


The major plant communities in the dry lowlands are candelabra cactus (Jusminocerecus thouarsii) communities, prickly pear (Opuntia species) communities, and Palo Santo (Bursera graveolens) forests.

Candelabra cactus communities (205) develop in a habitat where lava blocks are exposed on the ground surface, and prickly pear communities develop where lava is mixed with some soil (213).

Candelabra cactus communities prickly pear communities
  No.205   No.213

Palo Santo trees coexist there to some extent, and also grow in habitats with little lava (402). Palo Santo is a rain-green deciduous tree (140) and exposes a white bark after shedding leaves during the dry season (137, 138, 51).

Palo Santo trees
  No.402 No.140
Palo Santo trees during dry season
  No.137 No.138 No.51

In those communities, the following plants grow: Jerusalem thorn (Parkinsonia aculetata) (142), Galapagos croton (Croton scouleri) (156), Galapagos lantana (Lantana peduncularis) (150), Galapagos running pop (Passiflora foetida var. galapagensis) (177), Galapagos castella (Castela galapagensis) (228), and yellow cordia (Cordia lutea) (148).

Parkinsonia aculetata Croton scouleri
  No.142   No.156
Lantana peduncularis Passiflora foetida var. galapagensis
  No.150   No.177
Castela galapagensis Cordia lutea
  No.228   No.148

In the Transition Zone from dry lowland to mid-elevations, cacti disappear and Palo Santo trees predominate (401). Increased air humidity supports epiphytes on Palo Santo branch tips, such as pendent lichens, liverworts (264, 265) and ferns. Ferns also appear on the ground.

cacti disappear and Palo Santo trees predominate
  No.401
lichens, liverworts ferns
  No.264   No.265

There are the following three kinds of communities in moist mid-elevations: Scalesia pedunculata forest (71, 72), cat°«s claw (Zanthoxylum fagara) commnity (311), and Miconia robinsoniana community (584, 310).

Scalesia pedunculata forest
  No.71 No.72
Zanthoxylum fagara
  No.311
Miconia robinsoniana community
  No.584 No.310

Forests of endemic Scalesia species develop in middle-altitude areas above the transition zone (71, 79). Galapagos guava (Psidium galapageium) (308) is the only tree that grows in the communities, making them nearly pure Scalesia forests. Reflecting high air humidity, bryophytes are an epiphyte on high branches in the forests (266). The ground vegetation is composed of several species of shrubs (312, 314, 317) and ferns (292, 295) on the ground and a vine, Colinvaux°«s passionflower (Passiflora colinvauxii) (321) in the forest fringe.

Forests of endemic Scalesia
  No.71 No.79
Psidium galapageium
  No.308
bryophytes
  No.266
shrubs
  No.312 No.314 No.317
ferns
  No.292 No.295
Passiflora colinvauxii
  No.321

Well developed Scalesia forests are known to be affected by environmental changes, such as extremely dry weather and excessive rainfall, and can suffer massive dieback (see other sets of photographs).

On Santa Cruz, cat°«s claw forest (311) had existed in areas immediately above the Scalesia forest belt, but agricultural exploitation in the past destroyed the natural forest of this species and left sporadic remnant trees there. The environment is favorable for epiphytes (341, 322, 324, 348). Miconia robinsoniana is a shrub two meters high (584, 310) and forms pure communities above the cat°«s claw belt. Galapagos tree fern (Cyathea weatherbyana) (345) grows in the leeward side. Fern-Sedge vegetation spreads out in the area above the Miconia belt.

cat's claw forest
  No.311
epiphytes
  No.341 No.322 No.324 No.348
Miconia robinsoniana
  No.584 No.310
Cyathea weatherbyana
  No.345

High-altitude areas, 600-860 meters above sea level, of Santa Cruz are dried by high-temperature winds during the warm season (rainy season), whereas they are continuously enveloped by cloud and mist, and turn excessively humid during the garua season. Such extremely dry and extremely humid conditions do not allow any tree species to exist in such parts of the Galapagos. Thus, arboreous tree forests do not form in the highland; instead, treeless communities and bog formations have developed.

The main plants in the Fern-Sedge Zone (598, 775, 781) are ferns, such as bracken (Pteridium aquilinum var. archnoideum) (339) and sedges. In depressions, which are not hit by strong wind, the Galapagos tree fern (345) and a few species of shrubs (311, 312, 314) grow.

the Fern-Sedge Zone
  No.598 No.775 No.781
Pteridium aquilinum var. archnoideum
  No.339
Pteridium aquilinum var. archnoideum
  No.789 No.338 No.346
Cyathea weatherbyana
  No.345
shrubs
  No.311 No.312 No.314

There are bog formations (793, 794) in the highland. Raised Bogs (798) have developed in the old crater basins, and vertical bogs have developed (800) on the crater walls of cinder cones.

bog formations
  No.793 No.794
Raised Bogs
  No.798
vertical bogs
  No.800