Great variations in elevation and the availability of water have resulted in numerous microclimates throughout these two parks. In one section, you can see desert grasses, sagebrush, and a few cacti; while in another, not far away, there might be deep green woods where maidenhair ferns and cottonwood trees thrive. Zion National Park boasts over 900 species of plants -- considered the richest diversity of plants in Utah -- while at Bryce Canyon the number is a bit over 400. In the lower elevations, particularly in the hot, dry desert areas of Zion, you'll find cactus, mesquite, and yucca. As elevation increases, juniper and piñon are added, and eventually, in the high mountains of Bryce Canyon, you encounter a deep forest of fir and spruce, with stands of quaking aspen that turn a magnificent bright yellow each fall.

While exploring Zion, be sure to watch for spring lines and their lush hanging gardens, which you'll see clinging to the sides of cliffs. Because sandstone is porous, water can percolate down through it until a harder layer of rock stops it. At that point, the water simply changes direction, moving horizontally to the rock face, where it oozes out, forming the spring line that provides life-giving nutrients to whatever seeds the wind delivers.

Trees

Aspen -- The most widely distributed tree in North America, growing from Alaska to southern Arizona, quaking aspen are found in Utah, above 7,500 feet of elevation, mostly above the rim and in the mountains at the southern end of Bryce Canyon, and along the cliffs and plateaus at Zion. Named "quaking" for the trembling movement of the leaves at the slightest wind, aspens have white bark and almost heart-shaped green leaves that urn a striking yellow or gold in the fall. Deer and elk eat the twigs and leaves, and rabbits and other small mammals eat the leaves, buds, and bark.

Bristlecone Pine -- The oldest known trees -- some have lived more than 4,600 years -- bristlecones that are more than 1,600 years old can be found at Bryce Canyon, usually along exposed, rocky slopes above 7,500 feet of elevation. Bristlecones have very short dark-green needles, which grow all around each branch and are often tightly packed, and dark-brown, cylindrical cones. The trees commonly have a gnarled, weathered appearance, due at least in part to their age and choice of environment.

Cottonwood -- A member of the willow family, cottonwoods like lots of water and are usually found along streams or other permanent water sources. The narrowleaf cottonwood, found along water in Bryce Canyon, has skinny, green willowlike leaves that turn dull yellow in the fall. The Fremont cottonwood, found in almost all moist areas of Zion, has large, triangular-shaped, shiny yellow-green leaves that turn bright yellow in the fall.

Douglas Fir -- This large evergreen -- some can grow as tall as 200 feet -- has medium-size, blue-green needles and fairly large cones. Birds and various mammals eat the seeds, while deer eat the foliage. The Douglas fir is found at most elevations in the canyons and on the plateaus at Zion National Park. (There are good stands on the Kolob Terrace.) At Bryce Canyon, you'll find Douglas fir primarily above 7,500 feet of elevation, especially in the southern part of the park.

Juniper -- Two types of juniper -- Rocky Mountain and Utah -- grow in the parks, most often in canyons and on rocky slopes. Utah juniper are usually seen at the lower and drier elevations -- below the rim at Bryce Canyon -- while Rocky Mountain juniper will grow throughout the parks up to 8,500 feet of elevation. The Utah juniper has a short trunk and low spreading branches, with closely spaced yellow-green needles; the Rocky Mountain juniper is often taller, sometimes reaching 50 feet, with slender branches and short, gray-green needles. Both have berrylike cones that are a popular food for birds and other wildlife. The Utah juniper's "berries" are a dull blue, while the "berries" of the Rocky Mountain juniper are bright blue with a white coating.

Piñon Pine

 -- Common throughout the southern Rocky Mountains, between 5,000 and 7,000 feet of elevation, piñon are found at both parks, although mostly below the rim at Bryce Canyon. They are usually fairly small and somewhat gnarled, with rough bark and light green needles up to 1 1/2 inches long that usually grow in bundles of two. The small, egg-shaped cones produce edible seeds, often called nuts, which are a popular food for both humans and wildlife. The piñon jay takes its name from the tree and its tasty seeds.

Ponderosa Pine -- This large, impressive tree, which is found in both parks, is easily recognized by its long needles -- up to 10 inches -- that usually grow in bundles of three. Adult trees have orange-tinted bark that has a fragrance similar to vanilla, and large reddish-brown cones that are round or egg-shaped. At Zion, look for the ponderosa pine along cliffs and high plateaus; it is found at Bryce Canyon on sunny slopes above and along the rim, in the campgrounds, and around the lodge.

Shrubs & Ferns

Maidenhair Fern -- A surprise in southern Utah's generally arid terrain, this moisture-loving fern, known for its delicate, lacy fronds and thin black stems, thrives in select areas of Zion National Park, near sources of water such as the Emerald Pools, and in hanging gardens, including those at Weeping Rock.

Sagebrush -- Covering much of the American West, various types of sagebrush are found throughout Zion and Bryce Canyon. A shrub that normally grows in alkaline soil in arid areas, it can reach several feet tall, if it gets sufficient water. A common food for deer and other animals, sagebrush has a fresh, pungent scent -- strongest when it's wet -- that is similar to the spice sage. It has tiny, gray-green leaves and sprouts small, white flowers in the fall. Three varieties grow at Bryce Canyon: big, black, and fringed; while big and old man grow at Zion.

Yucca -- Not a cactus as many think, but a shrub, yuccas grow in dry, rocky areas of both parks. One of the prettiest plants in the Southwest -- absolutely stunning when it's in bloom -- the yucca was extremely important to early American Indians, who made baskets and sandals from its strong leaves, ate its fruits and flowers, and turned its roots into a shampoo. The plant has long, extremely tough green leaves with sharp spines on their tips that can be quite painful to the touch. In the spring or early summer, the yucca produces a tall stalk of large, white flowers. You'll find the narrow-leaf yucca at Bryce Canyon, and the Datil (broad-leaf) and Utah varieties at Zion.

Flowering Plants

Claret Cup Cactus -- One of 14 varieties of cactus found in the desert areas of Zion National Park, the claret cup boasts one of the park's most beautiful flowers and usually produces its brilliant red blooms in the spring, sometimes as early as March. The cactus stem (the body) is gray-green, cylindrical, 3 to 4 inches across, and covered with long, sharp, curved spines. As plants mature, numerous stems may grow, and they are stunning when covered with flowers.

Columbine -- A member of the buttercup family, columbine comes in a variety of shapes and colors. Flowers have five petals, but the overall appearance can vary quite a bit. Columbine usually prefers shady, moist areas, such as Zion's hanging gardens, but will also grow in rocky canyons and open meadows. Species at Zion are the golden columbine (with a beautiful yellow flower) and the western columbine (with red and yellow flowers). In Bryce Canyon, you'll find blue columbine (the Colorado state flower) in meadows above 7,500 feet and in the high forest at the southern end of the park. Blooming season is late spring and early summer at Zion, and from mid- to late summer at Bryce Canyon.

Larkspur -- Another member of the buttercup family, the larkspur is represented by several families in the drier areas of both parks, blooming in summer. Flowers are small -- about 1 inch across -- and are blue, violet, or white.

Prickly Pear Cactus -- One of the easiest types of cactus to identify, as well as one of the most common, prickly pears have flattened paddle-shaped pads covered with spines. You'll find them throughout the drier areas of both parks, up to about 8,500 feet. Prickly pear usually bloom in late spring or early summer at Zion, a little later in Bryce Canyon, and the cacti produce pretty flowers, about 2 to 3 inches across. Flowers are mostly bright yellow, but sometimes pink or magenta. The plains and Engelmann prickly pear you see at Zion are similar to the types usually encountered throughout the Southwest, with dull green pads and rigid spines an inch or so long. A bit unusual is the grizzly bear prickly pear that grows at Bryce Canyon. Although its pads are similar to other prickly pears, you can hardly see them because of what looks like long hair but are actually spines, which are flexible, white, and sometimes up to a foot long.

Sacred Datura -- Dubbed the "Zion Lily" because of its abundance in the park, the sacred datura has large, funnel-shaped white flowers that open in the cool of night and are often closed by noon the next day. You'll see them frequently along roadsides and other areas where the soil has been disturbed, generally in dry, sandy soil below 7,000 feet of elevation. Also called the Southwestern thorn apple, the sacred datura's flowers are 5 to 8 inches long and just as wide -- the largest blossoms of any plant in southern Utah -- and bloom from early spring to fall. Because it blossoms at night, it is also sometimes called the moon lily. Warning: The sacred datura is highly poisonous, and if any part of the plant is ingested, it is likely to cause hallucinations, convulsions, and quite possibly death.

Sego Lily -- Found in the drier areas below the rim in Bryce Canyon and in the canyons, cliffs, and plateaus of Zion, the sego lily has delicate white flowers, each about 1 to 2 inches wide. Flowers appear in late spring or early summer, and each is bell shaped, with three petals. The sego lily is the Utah state flower, and the state's early Mormon settlers ate the plant's bulbs when food was scarce.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.