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OSMP Nature Almanac and Favorite Hikes - July

OSMP Nature Almanac and Favorite Hikes - July

Hike of the Month - Arapaho Pass / Fourth of July Trailhead

OK, this trail is not actually part of the Open Space & Mountain Parks system, but the trailhead is located on a small parcel of OSMP land -- the Buckingham Campground at 10,100 feet elevation, near Eldora. The trail actually crosses land managed by the US Forest Service and enters the Indian Peaks Wilderness as it climbs to Arapaho Pass at nearly 12,000 feet. During July, the area explodes with alpine wildflowers: crimson Indian Paintbrushes, deep purple Monkshood and Larkspur, Rocky Mountain Columbines, pale blue Sky Pilot, and yellow Trout Lilies and Marsh Marigolds. Where streams crash down hillsides, look for hot pink Parry's Primrose. The trail crosses montane and subalpine life zones as it climbs to high, rocky tundra. At higher elevations, you'll see stunted trees twisted and deformed by harsh winds.

Please Note: Forest Service regulations for the wilderness area differ from the City of Boulder. Dogs must be on a hand-held leash at all times in the wilderness. Please visit the Indian Peaks Wilderness web site or contact the Forest Service at (303) 444-6600 for additional information on Forest Service lands and campgrounds in the Boulder area, as well as rules and regulations.

What's that Clicking?

During July, you may hear faint clicking sounds coming from trees and shrubs along hiking trails. These are cicadas, inch-long insects with bulbous eyes, long thick bodies and clear wings. Male cicadas produce the clicking sound to attract mates. They contract and expand a flexible membrane on their abdomen to create the sound, which echoes through hollow spaces in the body. There are over 2,500 species of cicadas in the world; some produce the loudest sounds emitted by an insect!

Cicadas have long life spans, for insects. Females lay eggs in the twigs of trees. When the young hatch out, they drop to the ground and burrow several feet down in search of tree roots, which they pierce with their sharp mouthparts to feed on sap. The young spend several years underground: 3-5 years for our common Putnam's cicada, up to 17 years for the famous "17-year locust" (actually a cicada) that occurs east of the Mississippi. At maturity, the cicadas return to the surface and climb up a tree trunk (or the side of your house) and shed their skin, emerging as a winged adult. They leave the skin behind, a hollow brown husk that resemble a tiny gremlin with sharp digging legs and bulging eyes.
Cicadas don't sting or bite, and do very little damage to the trees they feed on. See if you can spot one clinging to a tree branch next time you go for a hike!

Join the Butterfly Watch

Butterfly populations peak in July across the Open Space system. On just about any hike you'll notice many different species. Butterflies are most active on warm days. They often congregate in flower-filled meadows and in low-lying muddy areas where small streams cross trails. Butterflies feed on nectar which they gather from flowers with their long, hollow tongue or proboscis . They keep the tongue rolled up in a tight coil while flying. When a butterfly alights on a flower to feed, special muscles at the base of the proboscis force high pressure fluid into the tongue, causing it to elongate. The butterfly can then probe the depths of a flower in search of nectar, much like a kid slurping the dregs of a soda bottle with a long straw.

Baby butterflies--caterpillars--are picky eaters. Each species has its own preferred larval food plants. Choosy mothers will only lay eggs on plants that will appeal to their larvae. When the babies hatch from the tiny eggs, they immediately start eating and growing. After several weeks, larvae that haven't become bird food will pupate in a chrysalis (similar to a cocoon but not wrapped in a silken envelope).

Common butterflies on OSMP include Cabbage Whites (small white butterflies whose larvae feed on cabbage), Fritillaries (medium-sized brownish butterflies with round silver spots on their undersides), Tiger and Pale Swallowtails and small dark black Wood Nymphs that flutter about in meadows. OSMP is also home to some very rare butterfly species. The Hops Blue , a tiny blue butterfly, feeds on wild hops plants and is only known from a few areas along Colorado's Front Range. OSMP preserves habitat for this and other rare butterflies.

Did you know: The Front Range of Colorado has the fourth highest butterfly diversity of any place in the United States?

Congratulations! You've Fledged!

In July, baby Golden Eagles and Prairie and Peregrine Falcons fledge and leave the nest to soar over Boulder. These birds nest in the crags and cliffs overlooking the city, and will spend the rest of the summer in the area.

Keep your eyes peeled: the Mesa Trail and other trails at the base of the mountains are good places to see the new falcons. Listen for a high-pitched, "Keee! Keee! Keee! Keee!" and look to the skies. Falcons can be distinguished from other birds of prey by their streamlined shape and long, pointed swept-back wings. If you get a good look, you may be able to tell a Prairie (above) from a Peregrine (below). The former is more light colored and has grayish patches where the undersides of the wings attach to the body, whereas the latter has distinctive dark moustache marks.

Young Golden Eagles are also about. These very large, dark soaring birds may be seen close to the mountains, or out over they plains where they search prairie dog towns for a quick meal. Don't confuse Golden Eagles with the more common Turkey Vultures. Soaring eagles hold their wings flat, while vultures' wings bend upward in a "V" pattern. Vultures also tend to teeter from side to side as they soar.

The success of these magnificent birds is due in part to the wildlife closures that OSMP enforces during the breeding season. These raptor nesting closures open at the end of July. OSMP wants to thank all the people who have respected the closures, and the dedicated efforts of our Raptor Monitor Volunteers.

The Last Word

"And forget not that the earth delights to feel your bare feet and the winds long to play with your hair."

- Kahlil Gibran, (1883-1931) poet and novelist, author of "The Prophet."