Monitor Pass Flowers

By Bruce Homer-Smith,


Monitor Pass, on route 89, rises to about 8,300 feet and sits astride Alpine and Mono Counties.  Its open fields fill with spectacular mid-summer floral displays.  The plants shown here, all above 7,500 feet, are the ones you’re likely to notice.




Woolly Mule Ears (Wyethia mollis)


Photos Bruce Homer-Smith

Big yellow sunflowers are easy to see from far away.  Leaves are wide, long, and pointed, like mule ears.  2-3 feet tall.  more




Sulphur Buckwheat (Eriogonum umbellatum)


Photo ©Neil Kramer (left) and Steve Matson (right)

Low bunches of bright yellow flowers cover the hillside.  1-3 feet tall.  more


Antelope Bitterbrush (Purshia tridentata)

Photos Bruce Homer-Smith

This woody shrub is common in sagebrush chaparral, and fills the countryside with a yellow floral display after wet winters.  The paler plants in the first photo are sagebrush.  Grows to about 8 feet tall.  more


Tall Hawksbeard (Crepis acuminata)

Photos Keir Morse (left) and Bruce Homer-Smith (right)

Look for many dandelion-like flowers, each on its own branch.  Each flower head has 5 – 10 yellow “petals”.  Grows about 2 feet tall.  more


Woolly Sunflower (Eriophyllum lanatum)

Photos Keir Morse (left) and Bruce Homer-Smith (right)

This low-lying sunflower has 6-10 yellow “petals” and a yellow center.  The leaves are woolly, giving them a pale appearance.  more


Wallflower (Erysimum capitatum)

Photos Keir Morse

Wallflower is a member of the Mustard family.  Look for groups of 4-petaled flowers at the top of erect stems.  2-3 feet tall.  more


Tumble Mustard (Sisymbrium altissimum)

Photos Bruce Homer-Smith (left) and © Frank Rose (right)

Most flowers on Monitor Pass are native to California.  The Tumble Mustard, however, is a troublesome invasive that takes over open range land.  When it dries out, it becomes tumbleweed.  Like the Wallflower above it has 4-petalled yellow flowers, but they’re smaller and distributed all around the plant.  2-4 feet tall.  more



Blue Flag Iris (Iris missouriensis)

Photos Bruce Homer-Smith


The open fields to the south of Monitor Pass, on the west side of the road, are filled with this beautiful plant.  1-2 feet tall.  more


Silvery Lupine (Lupinus argenteus)

Photo Julie Kierstead Nelson (left) and Bruce Homer-Smith (right)

This lupine has long stalks of blue pea flowers rising above finger-shaped leaves.  1-2 feet tall.  more


Anderson’s Larkspur (Delphinium andersonii)

Photos Bruce Homer-Smith

Look for tightly-bunched dark blue spikes of flowers.  Up close the flower is distinctive with a long lip in front and a purple spur behind.  Leaves are narrow and divided.  1-2 feet tall.  more


Meadow Beardtongue (Penstemon rydbergii)

Photos Keir Morse (left) and Bruce Homer-Smith (right)

This is a Penstemon, with horizontal whorls of pale purple and blue trumpet flowers.  It has narrow leaves up to 2 inches long.  1-2 feet tall.  more


Royal Penstemon (Penstemon speciosus)

Photos Bruce Homer-Smith

Here’s another common Penstemon, with larger flowers and not in whorls but in bunches pointed in the same direction.  These leaves are less narrow, clasp the stem, and often fold in on themselves along their length.  Typically 1 foot tall.  more




Prickly Poppy (Argemone munita)

Photos Steve Matson

Big white poppy petals, and a yellow center, make this easy to spot.  2-5 feet tall.  more


Snowbrush Ceanothus (Ceanothus velutinus)

Photos © Neal Kramer (right) and Bruce Homer-Smith(left)

This is a woody shrub with large clusters of creamy white flowers.  They can cover a large area of a hillside in white.  The leaves are shiny on the top and pale underneath.  Grows to 20 feet tall.  more


Bitter Cherry (Prunus emarginata)

Photos © Neal Kramer (left) and Bruce Homer-Smith (right)

This is also a woody shrub, but with smaller bunches of flowers and often more space between the branches.  The leaves are slightly serrated and often fold in on themselves along their length.  Look for horizontal cherry lines on the bark.The bark often has a woody shrub with large clusters of creamy white flowers.  They can cover a large area of a hillside in white.  The leaves are shiny on the top and pale underneath.  Grows to 40 feet tall.  more


Cobweb Thistle (Cirsium occidentale)

Photos William Follette (left) and Steve Matson (right)

Peregrine Thistle (Cirsium cymosum)

Photos Keir Morse (left) and Steve Matson (right)


Both these thistles have spiny leaves and a sphere of spines at the base of the flower head.  Cobweb Thistle has cobwebby hairs throughout the plant, giving it a white appearance except for thin red or purple flowers that appear at maturity.  Peregrine Thistle is less hairy, and the flower itself is a brownish-white.  Both are typically 4 feet tall. 


Spur Lupine (Lupinus arbustus)

Photos Steve Matson

These lupine can be white or blue.  The flowers stand erect above wide finger-like leaves.  If you look closely, you’ll find a spur on the back of the pea flower.  Typically 2 feet tall.  more


Yarrow (Achillea millefolium)

Photos William Follette (left) and Barry Breckling (right)

Yarrow flower heads are flat and made up of many tiny white flowers.  Other plants have this pattern too but Yarrow’s leaves are definitive, with finely divided lobes and a spicy smell.  2-5 feet tall.  more


Spreading Phlox (Phlox diffusa)

Photos Keir Morse (left) and Bruce Homer-Smith (right)

This plant grows low to the ground, on a cushion of thin leaves.  Its white or pink petals are separate, and remind me of a pinwheel.   more


Mariposa Lily (Calochortus leichtlinii)

Photos Bruce Homer-Smith

This arresting plant is always fun to find.  Notice the purple markings, which distinguish it as Leichtlin’s Mariposa Lily.  1-2 feet tall. more


Brewers Angelica (Angelica breweri)

Photos by Barry Breckling (left) and Bruce Homer-Smith (right)

Angelica flowers form small spheres, grouped together in an umbrella shape, a pattern common in the Carrot family.  Its leaves are distinctive, made up of many leaflets.  3-6 feet tall.  more



Mountain Snowberry (Symphoricarpos rotundifolius)

 Photos Bruce Homer-Smith (left) and Barry Breckling (right)

This shrub is a thicket of narrow woody branches and 3/4-inch oval leaves.  The flowers start as hanging pairs of red buds, and then bloom white and pink.  They develop into snow-white berries.  From under a foot to 5 feet tall.  more


Waxy Checkermallow (Sidalcea glaucescens)

Photos Bruce Homer-Smith

Showy pink flowers are spread along the stem.  The leaves are pale gray, or waxy looking.  1-2 feet tall.  more


Sierra Onion (Allium campanulatum)

Photos Bruce Homer-Smith

Sierra Onion makes small balls of 6-petaled pink flowers.  Notice the papery bract at the base of the flowers.  Growing less than 1 foot tall, it is still easy to notice because of its beautiful color.  more



Wavy Leaf Paintbrush (Castilleja applegatei)

Photos Julie Kierstead Nelson (left) and Bruce Homer-Smith (right)


This paintbrush has wavy leaves up to 3 inches long.  The red at the top is actually colored leaves, which probably helps guide pollinators to the yellow flowers.   1-3 feet tall.  more




This area is a beautiful example of established native plants.  Lower on both sides of the pass, burned areas have been largely repopulated by fast-growing human-introduced weeds.  Let’s hope this pristine spot remains undisturbed for a long time.

Thanks to Tim Messick (U.C. Davis) and Ann Howald (Mono County CNPS) for their help identifying plants in this guide.


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