Caribbean Thornscrub - Code: Ne2J

Caribbean thornscrub can be quite varied in luxuriance and structure within a small area, yet over vast regions remain fairly constant. Thornscrub habitats may be divided into thorn savanna, thornscrub, thorn brush, and thorn thicket in regions like the Africa and Middle East and India, where all these forms have their own plant species assemblages. But in North America, the plants remain fairly uniform, and the bird assemblages of both thornscrub and thorn thickets are usually the same, so they are treated as a single habitat. 
Caribbean thornscrub habitat includes canopy trees that are 10 ft. to 27 ft. (3–9m) in height, deciduous, sclerophyllous, and microphyllous trees including Mexican logwood (Haematoxylon basiletto) which also grows in deciduous forests,  Trupillo ( Prosopis juliflora) which is invasive over much of the world, and Sweet Acacia (Acacia farnesiana). Where particularly dry or nutrient deficient, the canopy also contains cactus such as Caribbean Prickly Pear Cactus (Opuntia caribaea). Beneath it the mid-story is dominated by microphyllous plants and more widespread species such as Twisted Acacia (Acacia tortuosa), and cascalote (Caesalpinia coriaria). The ground cover has a seemingly incongruous combination of bushes such as Pyramid bush  (Melochia tomentosa), red spinach (Amaranthus dubius),  and bellyache bush (Jatropha gossypiifolia), all of which are introduced pests around the world, as well as cacti,  bromeliads and orchids. The abundance of Spanish Moss also seems out of place in this environment. 
Many of the deciduous shrubs flower during the dry season, when they don’t have leaves, creating a profusion of flowers in an otherwise spartan scene. Combined, these attributes of arid and wet environments together give the CARIBBEAN THORNSCRUB a distinctive feel within North America. Walking through this habitat is very difficult, as the mid story  brush layer is 3 ft (1m) to 9 ft (3m) tall and very thick.

Absolute rainfall can be high in these areas, but it is periodic, leaving prolonged spells of drought. It is the erratic and intense nature of the wet and dry seasons that promotes thornscrub over other types of arid vegetation, and the  dry, sandy soils  are the determining factor, and would promote a meathland in more temperate climates. Neotropical thornscrub forms over a wide variety of tropical conditions that are unfavorable for more lush forest growth. Cyclical extreme droughts stop more semi-evergreen forests from colonizing these areas. Aridity and locally harsh growing conditions are caused by a variety of factors. In some coastal locations, localized aridity is caused by easily drained sandy soils derived from the widespread limestones that were deposited in the late Cretaceous (80-65ma), and even more so on the very chemically inert tertiary sand deposits.