ZION Plants of Zion National Park

PLANTS OF ZION NATIONAL PARK

Families of Plants
(continued)

CALTROP FAMILY (ZYGOPHYLLACEAE)

CREOSOTE BUSH, Covillea tridentata. Although this shrub is uncommon in Zion, being confined to Coalpits Wash and lower Parunuweap Canyon, it is very important in the southwest as an indicator of the Lower Sonoran Zone. It is a widely branched, open shrub, about 6 feet tall, with very small varnished leaves having an acrid odor. Very common on low deserts along Highway 91 south of the park.

PARADISE-TREE FAMILY (SIMAROUBACEAE)

Near the south entrance, along the road, is a grove of AILANTHUS, Ailanthus altissima, originally planted by pioneer settlers. The trees can be easily recognized by their very thick twigs, and large pinnately compound leaves, resembling those of sumac.

SPURGE FAMILY (EUPHORBIACEAE)

A family of curious plants, usually with thick milky juice; many of them are used in rock gardens. The five kinds found in Zion are inconspicuous spreading "weeds" with small round or oval leaves and minute flowers. The following CARPET WEEDS are known from the park: Chamaesyce revoluta, Chamaesyce arenicola, Chamaesyce fendleri, and Chamaesyce albomarginata. Another member of the family, Croton longipes, is a woody perennial, 2 feet tall, with oval aromatic leaves; found in sandy places in Zion Canyon.

SUMAC FAMILY (ANACARDIACEAE)

This family of shrubs with alternate leaves and conspicuous berries is noted for the poisonous properties of some of its members.

POISON IVY, Toxicodendron rydbergii. This is the only one of our sumacs that is poisonous to man, and is fortunately not so very common. However, it should be watched for on any of the trails in Zion Canyon, especially The Narrows, Emerald Pools, and Weeping Rock. It is a low shrub easily recognized by the shiny leaves in 3's, pointed and slightly toothed near the outer end. Persons susceptible to the poisonous oil secreted by the leaves should wash in soapsuds, alcohol, or best of all, ferric chloride, soon after having touched the plant.

SQUAWBUSH, Rhus utahensis, is common in the Upper Sonoran Zone; a dense, diffusely branching shrub seldom over 6 feet high. The dry red berries, maturing in August, were used by the Indians for food, They are rather sour, hence the name "lemonade sumac" used in parts of the Southwest, A very similar bush, Rhus trilobata, is equally abundant, usually at slightly higher altitudes, and is known by the sane common names.

SUMAC, Rhus cismontana. An upright shrub or very small tree, with attractive clusters of red berries, and pinnately compound leaves that turn brilliant red in the fall. It is not common, but may be found near Weeping Rock, in the Court of the Patriarchs, and at Emerald Pools.

BITTERSWEET FAMILY (CELASTRACEAE)

MYRTLEBUSH, Pachistima myrsinites. A low semi-trailing under shrub found in the coniferous forests on the plateaus, most commonly in moist situations among fir trees. Flowers are inconspicuous; leaves glossy, small and oval, closely spaced on the stem in opposite pairs.

MAPLE FAMILY (ACERACEAE)

BIGTOOTH MAPLE, Acer grandidentatum. A small maple, seldom over 6 inches in diameter, found growing in moist places through out the park, often associated with red birch. It has smooth light gray bark, and small leaves (about 3 inches wide) which turn brilliant red in the fall.

DWARF MAPLE, Acer glabrum. A small, much-branched bush, with little, deeply-lobed leaves that often cause it to be mistaken for a wild currant. Moist places on the plateaus — not very common.

BOXELDER, Acer negundo interius. A very common tree in all the canyons where there is sufficient moisture, Its winged seeds and lobed leaves identify it as a member of the maple family. One of its most striking characteristics is the smooth green bark on twigs and small limbs. It is a short-lived tree, seldom exceeding 35 feet in height and a foot in diameter.

BUCKTHORN FAMILY (RHAMNACEAE)

DEER BRUSH is found on the plateaus, usually among yellow pines, but is not very common. It is a low, small-leaved shrub with spiny twigs and feathery clusters of white flowers (in June). It is often called "wild lilac", because the flower clusters resemble those of lilac on a small scale. It is a favorite browse of deer end domestic stock. In the park there is a small-leaved species, Ceanothus martini, and another with leaves about one-half inch wide, Ceanothus fendleri.

GRAPE FAMILY (VITACEAE)

ARIZONA GRAPE, Vitis arizonica. Wild grape vines are very common in all the major canyons and their branches, growing luxuriantly over trees and rocks. The fruit is small and sour but is greedily eaten by several species of birds. Deer relish the leaves and tender vines, often pruning them off as high as they can reach.

MALLOW FAMILY (MALVACEAE)

Cotton is a member of this large and important family, which also contains many ornamental plants such as hollyhock and hibiscia. In Zion it is represented by three kinds of GLOBEMALLOW, the flowers of which resemble small hollyhocks. (Plate VII). All are diffusely branched perennial herbs, 1 to 3 feet high, blooming profusely during May, June, and early July in dry localities below 5000 feet. In some of the desert areas south or west of the park they line the roadsides with masses of salmon colored blossoms. Sphaeralcea ambigua, Sphaeralcea elata, and Sphaeralcea fremontii are our three species; they are difficult to distinguish.

ST. JOHNSWORT FAMILY (HYPERICACEAE)

ST. JOHNSWORT, Hypericum scouleri. A perennial herb found in the cool canyons, but not very common. The plant consists of a single upright stalk, about 1 foot high, with oval opposite leaves throughout its length, and a cluster of yellow flowers at the top. It can be identified by holding the leaves to the light, when numerous small translucent dots will appear.

TAMARIX FAMILY (TAMARICACEAE)

TAMARICK, Tamarix gallica. This tree was originally introduced from Europe and planted along ditch banks by pioneer settlers. It has mow become naturalized and forms thickets on nearly every sand bar of the Virgin River and its tributaries. It is a low tree with very fine feathery twigs, foliage, and flowers (pink color). It is common in some of the villages south of the park.

VIOLET FAMILY (VIOLACEAE)

VIOLETS, and their cultivated relatives, the pansies, are well known by nearly everybody. The five kinds known in Zion nay be distinguished as follows:

LOASA FAMILY (LOASACEAE)

This family is represented in Zion by the BLAZING STARS, or "stickleafs", weedy plants with rough hairy leaves and smooth white or silvery stems; usually found along roadsides or on newly disturbed soil in the Sonoran Zones. All have yellow flowers (usually in June) with five pointed petals. They are notable as being among the few Zion flowers that bloom in bright sunlight during the hot drouth period of midsummer, mentioned in the introduction. Mentzelia multiflora and Mentzelia pumila have large showy flowers; Mentzelia ctenophora and Mentzelia albicaulis have very inconspicuous flowers.