Usery Mountain Park
Mesa, Arizona

Introduction

This Maricopa County Park, located northeast of Mesa preserves a fine example of Upper Sonoran Desert and provides many recreational opportunities for both visitors and residents. Drive north on Ellsworth Road from US-60. Ellsworth becomes Usery Pass Road then the park entrance is on the east side of the road north of McKelleps.

There is a campground and a horse staging area in addition to 20 trails. The park sets at the western end of the Goldfield Mountains and is adjacent to extensive Forest Service land. The most popular trail, The Wind Cave Trail, is located on national forest land. In the spring time parking spaces become limiting, so it is best to arrive early for a hike.

The Geology is primarily volcanic. The lower slopes and flats of Pass Mountain are alluvium from adjacent volcanic rocks. The base of Pass Mountain is ancient weathered granite and then there is a cap of yellow and brown volcanic tuff/rhyolite. The wind cave is formed at the boundary between the tuff and granite. Water seeping from the roof of the cave supports hanging gardens of Four O'clocks and Rock Daisy.

The species lists given here are for the Wind Cave trail and Pass Mountain.

Google Map

Butterflies Common Springtime Butterflies. Hackberry Butterfly (Asterocampa leila) Painted Lady (Vanessa cardui) Pima Orange Tip (Anthocharis pima) Sara Orangetip (Anthocharis sara) Pygmy Blue -- Brephidium exile

Western Pygmy Blue (Brephidium exile) This is probably the World's smallest butterfly species. Sara Orange Tip (Anthocharis sara) Photos from AZ Butterflies

Cacti

WILDFLOWER REPORT

April 2, 2000

Trail up to Wind Cave. Ocotillo and Chuparosa with their bright red flowers are the most conspicuous blooms.

Brittle Bush Asteraceae Encelia farinosa	Yellow-Bright	5 cm dia. daisies	shrub mostly 1 m tall; leaves usu. silvery soft	Just a few now, fair number of buds, more to come soon.; Road and hillsides
Desert Marigold Asteraceae Baileya	Yellow-Bright	All yellow daisy, up to 6 cm dia.	Flowers on tall stems from basal rosette	A few blooming around parking areas and roadsides
Chuparosa Acanthaceae Justica californica	Bright Red	long tubular flowers	shrub mostly ca. 1 m tall	Very conspicuous - at peak of blooming period!
Triangle-leaf Bursage Asteraceae Ambrosia deltoidae	Green -Yellow Pollen	No petals. Spikes of green clusters	shrub mostly < 1 m tall	Just a few now, probably won't bloom much this year; A dominant shrub. Causes hayfever
Canyon Ragweed Asteraceae Ambrosia ambrosioides	Green	no petals. many on a spike	1 to 2 m tall. Causes hay fever. Large, course leaves	Just a few now; In and along desert washes, roadsides
Trixis Asteraceae Trixis californica	Yellow	1 cm across. Composite.	Dark green leafy sub-shrub. Less than 1 m tall	Just a few now, lots of buds, many to come soon.; esp. in shade of Palo Verdes or boulders
Comb Bur Boraginaceae Pectocarya	White	Minute w/4 or 5 petals	Most plants are less than 3 cm tall at maturity!	Most abundant wildflower today; Especially on flats
Jojoba Buxaceae Simmondsia	Green	No petals. Separate male and female shrub	A woody shrub 1 - 1.5 m tall	abundantly blooming now; Rocky slopes; Wash banks
Engelmann Hedgehog Cactaceae Echinocereus engelmanii	Magenta	large blooms with many petals	Grows in spiny clumps of 10 to 30 stems up to 40 cm tall. Spectacular.	Just buds now, many to come soon.; Rocky slopes.
Narrow-leaf Ditaxis Euphorbiaceae Argythamnia	White-green	5 petals, 3 mm, inconspicuous	Small slightly woody herb with silvery leaves	Fairly common now; hillsides among rocks
Ocotillo Fouquieriaceae Fouqueria splendens	Red	22 mm, Tubular	Flowers are at top of 3 to 6 m tall arching thorny branches	Common; Slopes and desert flats
Filaree Geraniaceae Erodium	Lavender	lowers small w/5 petals	herb growing almost flat on soil; leaves often tinged red.	Rare; Near roads and parking areas. Geranium scented leaves
Eucrypta Hydrophylaceae Eycrypta	Sky Blue	5 petals, 4 mm across	Herb. 50 cm tall. Loose scorpioid inflorescence. Minute stiff hairs.	Rare; esp. in shade of bushes and trees
Desert Globe Mallow Malvaceae Sphaeralcia ambigua	Orange-Red-Pink	About 15 mm wide & 5 petals	Robust shrubby herb 2 m tall	Uncommon; Along roadsides, wash banks, and hillsides
Fairy Duster Mimosoideae Calliandra	Pink	A puff-ball cluster of anther filaments	A woody shrub < 0.5 m tall	Uncommon now but many with buds to bloom later; Rocky hillsides, slopes, road edges
Bigelow's Four O'Clock Nyctaginaceae Mirabilis bigelovii	White-Pink	5 petals, 12 mm across	Herb trailing over low twigs of bushes. Leaves sticky and opposite on stems.	Common; Below Palo Verdes, next to boulders
Bottle Evening Primrose Onagraceae Oenothera primiveris	Yellow	8mm, 4 bilobed petals	herb. Pinnately lobed leaves. 8 Stamens	Uncommon; might not have a chance to bloom. slopes, roadsides
Flat-topped Buckwheat Polygonaceae Eriogonum fasciculatum	White-Pink	6 sepals tinged pink. Many crowded together.	Woody bush up to 1 m tall	common; Rocky slopes
Wright's Buckwheat Polygonaceae Eriogonum wrightii	White-Pink	6 whitish sepals	Somewhat shrubby. 50 cm tall. Leaves pubescent.	Uncommon; shady spots, rocky slopes
Wolf Berry Solanaceae Lycium 2 spp.	Cream-Purple	4 mm long tubes w/4 or 5 pts.	Woody shrubs, 2 m, with some thorns. Hummingbird plant. Gets red berries.	Common; hillsides, washbanks
Creosote Bush Zygophyllaceae Larrea	Yellow	5 petals, 15 mm across	dark green shrub w/fuzzy seeds	Just a few now, lots of buds, many to come soon.;
Sweet Bush Asteraceae Bebbia juncea	Yellow-Orange	Disc flowers only, no rays	Favorite butterfly shrub	Common; hillsides
Rock Daisy Asteraceae Perityle	White-Yellow	2 to 3 cm, White rays and yellow centers		Growing as a hanging garden inside the wind cave
Fetid Marigold Asteraceae Dyssodia porophylloides	Orange	inconspicuous, no rays	strongly scented	Common; rocky slopes

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Copyright Michael J. Plagens, 1999-2008