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1.0 Introduction
Pine rocklands are one of the priority ecosystems for conservation efforts in the Miami-Dade
County (MDC) Environmentally Endangered Lands (EEL) Program. As settlers arrived in the
area that is now Miami-Dade County, they found that rocklands in the Miami Rock Ridge, in
general, were the most suitable areas for settlement. The relatively high elevation of the pine
rocklands in the landscape provided reasonable protection against flooding, while allowing the
people to remain close to valuable natural resources such as agricultural soils, timber, and
fisheries.
Unfortunately, this ecosystem has now been almost entirely destroyed by agricultural, urban, and
suburban development. Current estimates suggest that less than 1.8% of the original 126,500
acres of pine rockland ecosystem outside of Everglades National Park (ENP) remains today in
Miami-Dade County. These approximately 2,273 acres of pine rocklands exist in scattered, small
parcels. Furthermore, the pine rockland fragments that do remain have suffered from impacts of
forest fragmentation, fire suppression, exotic pest invasions, and other forms of disturbance.
Therefore, pine rockland fragments that have been acquired by the EEL program must be
managed to ensure their long term viability.
1.1 Overview of the Pine Rockland Ecosystem
The pine rockland ecosystem is the most diverse ecosystem in the EEL program. This ecosystem
contains a wide-ranging assemblage of rare plants and animals. Many organisms restricted to the
habitat are endemic, occurring nowhere else in the world. These organisms are part of a diverse
system that is influenced by a number of natural stressors, such as fires, the regular occurrence of
tropical cyclones, and the rather sporadic incidence of frosts. These natural processes shape the
structure and composition of pine rocklands and determine the ecological characteristics of the
ecosystem.
The pine rockland ecosystem is a pine woodland growing in a thin layer of sand or loam in a
matrix of exposed oolitic limestone substrate. Pre-drainage hydrology of pine rocklands varied
greatly depending upon elevation, with some pine rocklands probably never flooding and others
probably flooding annually for short periods during the summer wet season. Typically pine
rocklands consist of three vegetation layers – a canopy, a subcanopy, and an herb layer. The
canopy of pine rocklands is dominated by a single species, South Florida slash pine1
. The
subcanopy of pine rocklands consists of an array of temperate and tropical hardwoods and palms.
Palms in this layer include saw palmetto, cabbage palm, and silver palm, with saw palmetto
being the most common and typically a dominant species in all pine rockland areas. The herb
layer consists of temperate and tropical forbs, grasses, ferns, and sedges. At present, examples of
the common herbs in pine rocklands are the pine fern, low rattlebox, and Florida five-petalled
leafflower (Bradley, unpublished data).
Pine rockland occurs in South Florida and on several islands in the Bahamian archipelago. In
southern Florida, it is found in Miami-Dade County, Monroe County in the lower Florida Keys,

1 For reference, a table of all species common names and equivalent scientific names discussed throughout the
management plan is provided in Appendix A.
EEL Program, Management Plan, Part II – Pine Rockland (DRAFT) _____________________________________________________________________________________________________________________
Page 2
and small areas of the Big Cypress National Preserve in Collier and Monroe counties. This
chapter will focus on the pine rockland ecosystem in Miami-Dade County, where the ecosystem
has been almost entirely destroyed by agricultural, urban, and suburban development. Only
scattered, small parcels remain today. The pine rockland fragments that do remain have suffered
from impacts of forest fragmentation, fire suppression, exotic pest invasions, and other forms of
disturbance. Fragments that have been acquired by the EEL program must be managed to ensure
their long term viability.
1.2 Purpose
The purpose of this plan is to contribute to the preservation of the natural resources in pine
rockland sites owned and/or managed by EEL. To achieve this purpose, this management plan
provides:
• A brief description of the values and justification for conservation of pine rocklands
• A historical perspective of pine rockland presence in the landscape of the county
• Current conditions of the pine rockland habitat
• Main threats to the pine rockland habitat
• Perceived trends within the pine rockland habitat
• Management issues that are important to conservation of pine rocklands
• Guidelines for future public use
• Priorities for monitoring and research
This plan draws from other resources, including the Restoration Plan for Dade County’s Pine
Rockland Forests Following Hurricane Andrew (DERM 1995), the Miami-Dade County Habitat
Management Plan (Miami-Dade County Natural Areas Management Working Group 2004), and
the pine rockland chapter of the South Florida Multi-Species Recovery Plan (USFWS 2000).
Recommendations from these documents, as well as many other resources cited in the references
section, have been reviewed, and when relevant and acceptable, used in this management plan.
This chapter is intended not only to guide management of pine rocklands on EEL sites, but also
other pine rockland fragments in Miami-Dade County.
EEL Program, Management Plan, Part II – Pine Rockland (DRAFT) _____________________________________________________________________________________________________________________
Page 3
2.0 Historical Reference Conditions for the Pine Rockland Ecosystem
This section describes the historical condition of Miami-Dade County pine rocklands, as they
existed prior to major human disturbance. In considering conservation goals and alternatives, the
historical condition described is regarded as the baseline for the ecosystem. Utilizing these
conditions as a basis for weighing the importance of conservation efforts will aid in the
preservation of the valuable resources associated with pine rocklands in Miami-Dade County and
South Florida overall.
2.1 Original Pine Rockland Distribution in Miami-Dade County
Pine rockland in Miami-Dade County historically occurred on the Miami Rock Ridge. The
Miami Rock Ridge is an oolitic limestone formation that extends from north of downtown Miami
in a southwesterly arc to Mahogany Hammock in ENP, varying in width from four (4) to ten (10)
miles. In historic conditions, the ridge was at a higher elevation than the adjacent marshes of the
Everglades, with small wetland prairies dissecting the ridge into numerous, distinct islands
(Figure 1). This matrix of limestone and prairies allowed the Everglades to drain into Biscayne
Bay.
On the Miami-Rock Ridge, pine rockland was historically the dominant habitat. Of the 151,000
acres that the ridge historically occupied, almost all of the area was pine rockland. Only small
areas of the ridge were occupied by rockland hammock or other ecosystems.
2.2 Physiography
As discussed above, pine rocklands in Miami-Dade County occur on the Miami Rock Ridge.
This ridge varies in elevation between two (2) and 20 feet above sea level. Elevations are highest
in the Coconut Grove area and generally decline to the south (Craighead 1971). Other relevant
aspects of the physiography (geology, soils, and hydrology) of the pine rocklands are discussed
in the paragraphs below.
2.2.1 Geology
The geology and soils of Miami-Dade’s pine rocklands have a relatively simple structure and are
derived from recent geologic history. The surface rocks of the county, exposed in many

1.0 Introduction

Pine rocklands are one of the priority ecosystems for conservation efforts in the Miami-Dade

County (MDC) Environmentally Endangered Lands (EEL) Program. As settlers arrived in the

area that is now Miami-Dade County, they found that rocklands in the Miami Rock Ridge, in

general, were the most suitable areas for settlement. The relatively high elevation of the pine

rocklands in the landscape provided reasonable protection against flooding, while allowing the

people to remain close to valuable natural resources such as agricultural soils, timber, and

fisheries.

Unfortunately, this ecosystem has now been almost entirely destroyed by agricultural, urban, and

suburban development. Current estimates suggest that less than 1.8% of the original 126,500

acres of pine rockland ecosystem outside of Everglades National Park (ENP) remains today in

Miami-Dade County. These approximately 2,273 acres of pine rocklands exist in scattered, small

parcels. Furthermore, the pine rockland fragments that do remain have suffered from impacts of

forest fragmentation, fire suppression, exotic pest invasions, and other forms of disturbance.

Therefore, pine rockland fragments that have been acquired by the EEL program must be

managed to ensure their long term viability.

1.1 Overview of the Pine Rockland Ecosystem

The pine rockland ecosystem is the most diverse ecosystem in the EEL program. This ecosystem

contains a wide-ranging assemblage of rare plants and animals. Many organisms restricted to the

habitat are endemic, occurring nowhere else in the world. These organisms are part of a diverse

system that is influenced by a number of natural stressors, such as fires, the regular occurrence of

tropical cyclones, and the rather sporadic incidence of frosts. These natural processes shape the

structure and composition of pine rocklands and determine the ecological characteristics of the

ecosystem.

The pine rockland ecosystem is a pine woodland growing in a thin layer of sand or loam in a

matrix of exposed oolitic limestone substrate. Pre-drainage hydrology of pine rocklands varied

greatly depending upon elevation, with some pine rocklands probably never flooding and others

probably flooding annually for short periods during the summer wet season. Typically pine

rocklands consist of three vegetation layers – a canopy, a subcanopy, and an herb layer. The

canopy of pine rocklands is dominated by a single species, South Florida slash pine1

. The

subcanopy of pine rocklands consists of an array of temperate and tropical hardwoods and palms.

Palms in this layer include saw palmetto, cabbage palm, and silver palm, with saw palmetto

being the most common and typically a dominant species in all pine rockland areas. The herb

layer consists of temperate and tropical forbs, grasses, ferns, and sedges. At present, examples of

the common herbs in pine rocklands are the pine fern, low rattlebox, and Florida five-petalled

leafflower (Bradley, unpublished data).

Pine rockland occurs in South Florida and on several islands in the Bahamian archipelago. In

southern Florida, it is found in Miami-Dade County, Monroe County in the lower Florida Keys,

1 For reference, a table of all species common names and equivalent scientific names discussed throughout the

management plan is provided in Appendix A.

EEL Program, Management Plan, Part II – Pine Rockland (DRAFT) _____________________________________________________________________________________________________________________

Page 2

and small areas of the Big Cypress National Preserve in Collier and Monroe counties. This

chapter will focus on the pine rockland ecosystem in Miami-Dade County, where the ecosystem

has been almost entirely destroyed by agricultural, urban, and suburban development. Only

scattered, small parcels remain today. The pine rockland fragments that do remain have suffered

from impacts of forest fragmentation, fire suppression, exotic pest invasions, and other forms of

disturbance. Fragments that have been acquired by the EEL program must be managed to ensure

their long term viability.

1.2 Purpose

The purpose of this plan is to contribute to the preservation of the natural resources in pine

rockland sites owned and/or managed by EEL. To achieve this purpose, this management plan

provides:

• A brief description of the values and justification for conservation of pine rocklands

• A historical perspective of pine rockland presence in the landscape of the county

• Current conditions of the pine rockland habitat

• Main threats to the pine rockland habitat

• Perceived trends within the pine rockland habitat

• Management issues that are important to conservation of pine rocklands

• Guidelines for future public use

• Priorities for monitoring and research

This plan draws from other resources, including the Restoration Plan for Dade County’s Pine

Rockland Forests Following Hurricane Andrew (DERM 1995), the Miami-Dade County Habitat

Management Plan (Miami-Dade County Natural Areas Management Working Group 2004), and

the pine rockland chapter of the South Florida Multi-Species Recovery Plan (USFWS 2000).

Recommendations from these documents, as well as many other resources cited in the references

section, have been reviewed, and when relevant and acceptable, used in this management plan.

This chapter is intended not only to guide management of pine rocklands on EEL sites, but also

other pine rockland fragments in Miami-Dade County.

EEL Program, Management Plan, Part II – Pine Rockland (DRAFT) _____________________________________________________________________________________________________________________

Page 3

2.0 Historical Reference Conditions for the Pine Rockland Ecosystem

This section describes the historical condition of Miami-Dade County pine rocklands, as they

existed prior to major human disturbance. In considering conservation goals and alternatives, the

historical condition described is regarded as the baseline for the ecosystem. Utilizing these

conditions as a basis for weighing the importance of conservation efforts will aid in the

preservation of the valuable resources associated with pine rocklands in Miami-Dade County and

South Florida overall.

2.1 Original Pine Rockland Distribution in Miami-Dade County

Pine rockland in Miami-Dade County historically occurred on the Miami Rock Ridge. The

Miami Rock Ridge is an oolitic limestone formation that extends from north of downtown Miami

in a southwesterly arc to Mahogany Hammock in ENP, varying in width from four (4) to ten (10)

miles. In historic conditions, the ridge was at a higher elevation than the adjacent marshes of the

Everglades, with small wetland prairies dissecting the ridge into numerous, distinct islands

(Figure 1). This matrix of limestone and prairies allowed the Everglades to drain into Biscayne

Bay.

On the Miami-Rock Ridge, pine rockland was historically the dominant habitat. Of the 151,000

acres that the ridge historically occupied, almost all of the area was pine rockland. Only small

areas of the ridge were occupied by rockland hammock or other ecosystems.

2.2 Physiography

As discussed above, pine rocklands in Miami-Dade County occur on the Miami Rock Ridge.

This ridge varies in elevation between two (2) and 20 feet above sea level. Elevations are highest

in the Coconut Grove area and generally decline to the south (Craighead 1971). Other relevant

aspects of the physiography (geology, soils, and hydrology) of the pine rocklands are discussed

in the paragraphs below.

2.2.1 Geology

The geology and soils of Miami-Dade’s pine rocklands have a relatively simple structure and are

derived from recent geologic history. The surface rocks of the county, exposed in many