About the Rare Plant List
The primary goal of the New Mexico Rare Plant Technical Council is to develop and maintain a list of New Mexico rare plants. Criteria for inclusion
of taxa, and an explanation of the R-E-D Code are on this page.
Criteria for Inclusion
Having a consistent and objective definition of
rarity is necessary to evaluate all the species proposed as potentially rare. Plants
with narrow habitat specificity and small range are automatically of concern, whether their populations are large or not. Other categories are
less clearly rare. A wide range and a narrow habitat are rare if the total number of populations is small. Plants that occur only in small
populations are rare if the number of those populations are limited. Disjunct populations with numerous populations outside the state of New
Mexico are cases where in a global view, the plants are not rare.
The NMRPTC will take a biological outlook and try not to read evolutionary potential into plant populations. The NMRPTC will include
sparse plants, those with large ranges but narrow habitats, and those of small ranges and narrow habitats. Some widespread but sparse plants will
be included on the basis of threats to their survival.
RARE = A taxon that is narrowly endemic to a specific geographic feature (e.g., mountain range; geologic outcrop) or subset area of a
phytogeographic region (e.g., southern Rocky Mountains, northern Chihuahuan desert). It can be locally abundant within its narrow range,
but typically will not extend more than 100 miles in length of range;
OR
A taxon that is more widespread, but is numerically rare - never locally common - throughout its range (e.g.,
Peniocereus greggii)
or is numerically abundant only in a few small, widely scattered habitats (e.g.,
Puccinellia parishii, Helianthus paradoxus).
The R-E-D Code
The R-E-D Code concept has been so useful to the California Native Plant Society in developing the Inventory of Rare, Threatened and
Endangered Plants of California (CNPS, 1994), that we developed a system that is similar, but is slightly different for the rarity ranking. This
code presents a three element ranking that gives a great deal of information about each plant in a glance. The three components are
rarity,
endangerment and
distribution that together form the
R-E-D Code. Each element in the code is divided into three
classes or degrees of concern, represented by the number 1, 2 or 3. In each case, the higher the number, the more critical the concern. The
system is defined as follows:
R (Rarity)
- 1: rare, but found in sufficient numbers and distributed widely enough
that the potential for extinction is low for the foreseeable future
- 2: occurrence confined to several populations or to one extended
population
- 3: occurrence limited to one or a few highly restricted populations,
or present in such small numbers that it is seldom reported
E (Endangerment)
- 1: not endangered
- 2: endangered in a portion of its range
- 3: endangered throughout its range
D (Distribution)
- 1: more or less widespread outside New Mexico
- 2: rare outside New Mexico
- 3: endemic to New Mexico
About the Map Data
In using this web site you may discover some differences between the reports and their distribution maps. Location information shown on the maps was obtained from
herbarium specimen records, agency databases, and the scientific literature. Some map points may represent data entry errors or misidentified specimens in our herbaria,
which highlights the need to re-examine specimens and annotate them where appropriate. Other map points may represent range extensions that were unknown to the author of the
report. Resolving cases where reports and maps differ is an ongoing process and we will modify our web site as these differences are identified and resolved. Please contact us
if you have information that will help in this effort.