Alternanthera repens Tr.
Anisolotus trispermus (bird's-foot trefoil) 186
Aplopappus gracilis 1,030
Apodanthera undulata (melon loco) 55
Astragalus nuttallianus (milk vetch) 630
Ayenia microphylla Tr.
Boerhaavia wrightii 885
Chamaecrista leptadenia (partridge pea) 5
Echinocactus wislizeni (visnaga) 5
Eriogonum polycladon 35
Eschscholtzia mexicana (Mexican poppy) 250
Gaertneria tenuifolia (franseria) Tr.
Collomia gracilis (false gilia) Tr.
Heterotheca subaxillaris Tr.
Kallstroemia laetevirens Tr.
Lupinus sparsiflorus (lupine) Tr.
Martynia altheaefolia (small devil's-horns) 12
Mollugo verticillata (carpetweed) 324
Oenothera primiverus (evening primrose) 15
Opuntia discata (prickly pear) 15
Loeflingia pusilla Tr.
Lepidium lasiocarpum (peppergrass) Tr.
Plantago ignota (plantain) 818
Polygala puberula (milkwort) Tr.
Portulaca suffrutescens (purslane) Tr.
Prosopis velutina (mesquite) 1,570
Sida diffusa (spreading sida) 30
Solanum elaeagnifolium (742 fruits) (trompillo, prickly solanum) 156
Puffballs and fleshy fungi (undetermined) 12
Total species, exclusive of fungi, 41.
It will be seen from Table 3 that while a large number of species of
plants are represented in the totals from so many dens, a majority of
them are of very minor importance, and that the seeds of grasses are the
principal storage and probably therefore the principal food material.
Six of the most important species of grasses (disregarding species
furnishing less than 5 grams) comprise 85.6 per cent of the total weight
of storage from 22 dens. Crowfoot grama (_Bouteloua rothrockii_) stands
first in quantity in the total, forming 39.4 per cent of all stored
material, 46 per cent of the six important grasses, and 45 per cent of
all grasses. The largest amount of storage of any one species of grass
in any one den on the Range Reserve also is of this species, 2,205
grams[5] (Table 1, den 1, p. 20, and Pl. VII, Fig. 2). This is exceeded
by a dropseed grass, _Sporobolus cryptandrus strictus_, which amounted
to 5,455 grams in a lot from Albuquerque, N. Mex. (Table 1, den 24, and
Pl. VIII, Fig. 1).
[Footnote 5: This amount of dry grama grass seed (heads) amounts to
approximately a bushel.]
Of the species other than grasses found stored in these dens, mesquite
beans (_Prosopis velutina_) are most important both by weight and number
of dens containing them. The total for the 22 Range Reserve dens is
1,570 grams, or 35.9 per cent of the seeds other than grasses, but only
5.1 per cent of the total storage. In bulk mesquite beans do not loom up
large, as they are probably the heaviest material stored. Sections of
pods which must have been dragged into the burrows are found, some of
them certainly being much too long for carriage in the pouches. The
species of plant other than grass found in the largest quantity in any
one den, however, was _Aplopappus gracilis_, not recorded in quantity
from any den until the excavation of the twenty-second, and then found
in a very large bulk of soft, fluffy material, with most of the seeds
separated from the heads, and weighing 1,030 grams (Table 1, den 22).
Any of the food materials above listed are likely to be found in the
cheek pouches, while in addition such extraneous matter as stones and
feces have also been found. All species of plants stored are accessible
in the immediate vicinity of the mound, and when any particular plant is
found seeding in abundance in the vicinity of the den it is likely to be
represented in the storage. Usually the animals can be readily trapped
with almost any kind of grain bait, as oats, rolled oats, rolled barley,
and wheat; and nut meats also are attractive, though we have no record
of the storing of any true nut in the dens, such not being available in
the range of the animal on the Range Reserve.
The following plants not represented in the list stored by the kangaroo
rat on the Range Reserve have been found in the cheek pouches or mounds
of _spectabilis_ in other localities:
_Amaranthus palmeri_, _Sesuvium portulacastrum_, and _Atriplex
wrightii_ (alluvial soil of Santa Cruz Valley, Continental, Ariz.,
Bailey).
Cut leaves and stems of a small sagebrush (Franklin Mountains,
Tex., Gaut).
_Gutierrezia_ heads (San Juan Valley, N. Mex., Birdseye).
_Verbesina enceliodes_, _Portulaca oleracea_, _Bouteloua gracilis_,
and _Munroa squarrosa_ (Rio Alamosa, N. Mex., Goldman).
Tops of buds of _Artemisia filifolia_ (Mesa Jumanes, N. Mex.,
Gaut).
Tumbleweed (_Amaranthus graecizans_), Russian thistle (_Salsola
pestifer_), _Munroa squarrosa_, and _Sporobolus cryptandrus
strictus_ (Sandia Mountains, Albuquerque, N. Mex., Vorhies).