ILLUSTRATED FLORA OF EAST TEXAS - Brit - Botanical Research ...
ILLUSTRATED FLORA OF EAST TEXAS - Brit - Botanical Research ...
ILLUSTRATED FLORA OF EAST TEXAS - Brit - Botanical Research ...
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228 INTRODUCTION/CONSERVATION IN <strong>EAST</strong><strong>TEXAS</strong><br />
CONSERVATION IN <strong>EAST</strong> <strong>TEXAS</strong><br />
During the past 200 years, human activities, particularly logging, conversion of habitats for<br />
agriculture, flooding of river bottoms for reservoirs, urbanization, and other types of development,<br />
have profoundly altered the ecosystems of East Texas. Only tiny remnants of the original<br />
habitats have survived to the present day in anything resembling their presettlement state.<br />
This is particularly tragic, because in many ways, East Texas is a botanically unique region<br />
(Diggs 2002; also Appendix 10) and an area of high biological diversity. As a result of these<br />
changes, there are now numerous species that are of conservation concern (Appendix 12).<br />
Different organizations and agencies have tracked endangered, threatened, or rare species in<br />
the state over the years. Examples include the Texas Organization for Endangered Species<br />
(TOES 1993), the Nature Conservancy of Texas (Carr 2001, 2002d), and the Texas Parks and<br />
Wildlife Department (Poole et al. 2002).<br />
Several categories (sometimes overlapping) of such plants are of particular interest. Of<br />
greatest conservation concern are those plants that have an official designation such as<br />
“federally endangered” (see page 20 and Appendix 12). While these are limited in number,<br />
they generate great publicity and are potentially significant economically. Another large group<br />
of species is endemic to Texas (see page 215 and Appendix 11), and many of these are likewise<br />
vulnerable. Such plants are of major conservation concern because they are known from<br />
nowhere else in the world—they are unique aspects of Texas’ natural heritage. Finally,<br />
hundreds of species of plants reach the southwestern limits of their ranges in East Texas and<br />
are rare or of very limited occurrence in the state. Many of these species are probably Ice Age<br />
relicts, surviving only in a few areas of favorable microclimate or geology (Kral 1966c;<br />
MacRoberts & MacRoberts 1997a). Such species are particularly vulnerable to habitat change<br />
and could easily be eliminated from the state by the type of widespread habitat transformation<br />
now occurring throughout most of East Texas.<br />
Like individual species, a number of entire ecosystems/communities are currently of<br />
significant conservation concern. The Blackland Prairie (and its constituent communities),<br />
for example, originally covered a huge area but has been reduced to a few tiny remnants,<br />
more of which are lost each year. Communities on the Carrizo Sands, some of which are<br />
unique to Texas, are also under pressure, and what remains are often significantly degraded<br />
by grazing, fire exclusion, or other pressures (M. MacRoberts, pers. comm.). Further, a number<br />
of communities reach their western limit in Texas and are now vulnerable. Examples include<br />
wetland pine savannah (limited in Texas to Hardin, Jasper, Newton, and Tyler counties—<br />
MacRoberts & MacRoberts 1998d), hanging bogs (also known as hillside bogs or Wet<br />
Herbaceous Seeps), muck bogs, beech-magnolia forest, beech-hardwood forest, etc. These<br />
communities face various threats ranging from conversion to pine monoculture, fire suppression,<br />
drainage, overgrazing, cultivation, or invasion by exotics to total destruction by<br />
development. Each community faces a unique set of problems and, like individual species,<br />
these communities need protection, and in some cases active management, if they are to<br />
survive into the future.<br />
Among the most noteworthy large-scale conservation efforts in East Texas have been the<br />
creation of the National Forests, attempts to save part of the Big Thicket (see section on<br />
Conservation in the Big Thicket on page 190), the struggle to set aside wilderness areas in the<br />
National Forests, efforts to establish and expand a number of National Wildlife Refuges, and<br />
the successful creation of an extensive Texas State Park system. The results have included the<br />
establishment of the Big Thicket National Preserve, four National Forests (Figs. 89, 132), four<br />
major National Wildlife Refuges (including Caddo Lake created in 2000), and dozens of state<br />
parks and wildlife management areas (discussed further below). Another major event was the<br />
passage of the 1984 East Texas Wilderness Act, which resulted in five officially designated