Chapter II: Foreword (2)

Webster’s Dictionary describes fireweed as “any of several weeds, troublesome in clearings or burned districts.” To use “troublesome” in connection with this great “willow-herb” of the Rockies seems most unkind. We are grateful to have it rush into devastated areas to cover scars with its bright pink to magenta blossoms. The whole plant reddens as it ages. The flower matures into a long thin pod which splits and curls releasing feathery seed carriers. A less common low growing species with larger flowers and broader leaves, _Epilobium latifolium_, also grows in the area. It is a real find. A few grow not far below Loveland Pass.

Heath Family
Pipsissewa, _Chimaphila umbellata_, NUTT.

Flower, ½ inch across, formed of 5 rose-pink petals that bend back and surround, at the center, a conspicuous bright green ovary which is tipped with a disc-like stigma. The 10 prominent stamens, spreading from near the base of the ovary, look like short claws. Plant is 8-12 inches tall, bearing a cluster of several flowers at its top. Leaves are shiny and evergreen with saw-toothed edges, arranged in whorls along the woody stems, but most numerous at the base of the plant. Grows in moist acid soil under pine or spruce trees in montane zone. Blooms late July-August.

The members of the heath family like shade, acid soil and moisture. These conditions they find in the woods of the Northwest, where a great variety of them, including rhododendrons and azaleas, grow in abundance. Colorado has its share of the smaller heaths for those who look for them in shady spots and along mossy trails near mountain streams. The trail to Calypso Falls in Rocky Mountain National Park is good hunting, not only for pipsissewa, but for the pyrolas and for the tiny white wood-nymph, _Moneses uniflora_, all of them heaths. Kinnikinnick, _Arctostaphylos uva-ursi_, is a heath of prostrate growth habit quite common on mountain slopes. Bright red berries remain among its evergreen leaves until Christmas.

Primrose Family
Brook Primrose, _Primula parryi_, GRAY

Individual flowers, almost ½ inch across, are formed of 5 brilliant, crimson, spreading corolla lobes which join at their base into a narrow tube; dark shadings and yellow markings at the throat of the tube give the effect of a round eye. A dozen or more flowers, each on a nodding pedicel, are clustered at the top of a stout dark stem which rises from a whorl of deep-green, broad, lance-shaped leaves. Plant is about 10 to 20 inches tall. Grows in sub-alpine zone or slightly higher. Blooms June-early July.

This spectacular primrose grows at the edge of cold streams, or often on rocky-mossy hillocks right in mid-stream. One never forgets the picture of their beauty—the flower clusters so rich in color, the alpine background, the mat of moss and deep green leaves. Too bad for such a plant to spoil any part of it with a most disagreeable fragrance, yet that does remove any temptation to take them home. On the higher tundras, a charming find is the tiny fairy primrose, _Primula angustifolia_, similar in color, though not so vivid. A single short-stemmed flower is usually all that this plant carries.

Primrose Family
Shooting Star, _Dodecatheon radicatum_, GREENE

Individual flowers, ¾ inch across, are formed of 5 crimson, rather narrow, petals or corolla lobes which flare outward and backward, but unite at their base into a short tube. From this tube 5 conspicuous anthers, over ¼ inch long, grouped together like a sharp straight beak, protrude forward. Ten or more flowers, each on a slender pedicel, nod in a cluster at the top of a stout scape which rises 10 to 15 inches high from a basal mat of dark-green, oblong leaves. Grows along streams and in wet meadows, in montane and sub-alpine zones. Blooms June-early July.

Both the coloring and the shape of this little flower are fancy indeed. It is small wonder that such names as shooting-star and bird-bill have been given it. The crimson of its petals contrasts strongly with its conspicuous almost black “bill,” and between these colors is a little circlet of white, often shaded with yellow markings. A whole meadow of such flowers is a sight well worth a trip to South Park, or to other of our high meadow areas, where shooting-stars can be found in profusion. In blooming season they follow the wild iris and, in turn, they are followed by the low, red lousewort, _Pedicularis crenulata_, all of which can in favorable seasons give fine mass color effects.

Gentian Family
Fringed Gentian, _Gentiana elegans_, A. NELS.

Flowers are 2 to 3 inches long, of 4 deep purple-blue petals, fitted together to form a square column for over half their length, then, in sunlight, flaring outward to exhibit fringed tops and upper edges. Each flower is at the end of a stem which bears several pairs of oblong, opposite leaves. Plants are about 12 inches high of several erect stems branching from near the base. Grows in sub-alpine wet meadows. Blooms August-September.

The lush hay meadows of Colorado’s upland parks are bright through the summer with a succession of flowers. Late in the season come the gentians. There are several species of these (we have counted a dozen on a single trip), some of them quite uninteresting, weedy plants. The queen of them is the fringed gentian, growing in abundance along the edge of these high hay meadows, and even persisting in the stubble after haying is past. A few of them last into late September. The flowers close up under cloudy skies, but to find masses of them full-open on a sunny day, when they display their fringed petals and large golden stamens, is a heart-warming experience to be treasured for flowerless days ahead.

Milkweed Family
Milkweed, _Asclepias speciosa_, TORR.

Individual flower is a rosy, 5-point, star about ⅜ inch across, at the center of which is a group of 5 small appendages curving inward and forming a crown around the style and stamens. Numerous flowers cluster together into a ball about 3 inches in diameter. Plants are about 3 feet tall with thick broad leaves, the flower clusters borne at the top of the stem and in axils of upper leaves. Grows on plains, especially along ditch banks. Blooms June-July.

The common weeds are too often taken for granted and not appraised for their real beauty. This milkweed is in such a group—a coarse-growing plant along country roads, often dust covered, yet with flowers of fine delicate color and real charm whether we examine them singly or fix our attention on the compact cluster in which they grow. As autumn comes the dry leaves do not drop, but cling to the stem, rattling in the wind. The rough seed pods, often four inches long, turn a rich brown, and finally split open revealing a filling of lustrous, silky, down from which is gradually released the seeds—brown-clad paratroopers with the most airy-fairy parachutes in the world.

Morning-glory Family
Bush Morning-glory, _Ipomoea leptophylla_, TORR.

The flowers, shaped like pink trumpets with maroon striations, 3 inches long and 2 inches across the mouth, are scattered freely along the outer third of the stout yellowish stems which form a thick bush 2 feet or more high. New buds coming out each day keep the plant in bloom for the morning hours of several weeks. Leaves are narrow and linear, 2 inches long; the root is large and spongy. Grows in sandy soil on plains. Blooms July.

This morning-glory is no clinging vine, even though its flowers—like those of its cultivated relative on the back yard fence—do open only in the coolness of dawn and wither in the heat of noon. For all the sturdiness of individual plants, with their roots going “clear to China,” they do not seem to multiply rapidly and colonies of them may be miles apart. There are some fine bushes on the sandy hills along the Denver-Parker road, but the colony is becoming smaller rather than expanding. The common bindweed, _Convolvulus arvenis_, is a member of this same family. Its ability to spread rapidly along roads and into cultivated fields makes it a serious pest.

Waterleaf Family
Purple Fringe, _Phacelia sericea_, GRAY

Numerous purple flowers, each ¼ inch in diameter, crowd at and near the top of an erect hairy stem, making a cylindrical flower spike 3 inches or more in length. The 5 stamens of each flower are tipped with bright golden anthers and stick out farther than the petals, giving the effect of gold-headed pins radiating from a purple cushion. Plant is 6 to 12 inches tall of several leafy stems from a woody crown, the leaves divided into numerous narrow lobes. Grows in rather dry soil, montane to sub-alpine zones. Blooms May-July.

Many other species of _Phacelia_ live in desert places where we have learned to know and admire them, but our first acquaintance—and last love—is this purple fringe of the montane zone. Its color is deeper, more velvety, and the pollen of its anthers brighter gold than most of its desert brethren can boast. It keeps, however, considerable tolerance for dry places, so that fresh road-fills are gay with it. The mountaineer who views his flowers only from a car has no excuse for not knowing this one.

Borage Family
Alpine Forget-me-not, _Eritrichium elongatum_, JOHNSTON

Flowers, ⅜ inch in diameter, are formed of deep-blue (occasionally white) petals, spreading into a little flat disc and joining at their base into a short tube. Minute golden crests in the throat of this corolla tube, often bordered by white, give the effect of a central eye. Plant is formed of a tough woody root crown bearing several very short leafy shoots with flower clusters at the top. Entire plant is compact, covered with short silky hairs, and rarely 3 inches high. Grows on flat spots between rocks in alpine zone extending clear to peak summits. Blooms late June-early July.

The plant “association” pictured above is such as we find on Trail Ridge. It has bright lichen, sedum, polemonium and alpine forget-me-not—the kind of miniature garden that makes high altitude flower hunting so much fun. The woody base of the forget-me-not is built to stand the cold of long winters. The flowers—tiny and delicate for so rugged a habitat—are of heaven’s own blue. Their exquisite perfume is elusive. Only once have we found them in such abundance that the fragrance called out to tell us where they were hiding. Their range is wide, however, and in the short blossoming season there is a good chance of finding a few on the slopes of any of our high peaks.

Phlox Family
Sky Pilot, _Polemonium viscosum_, NUTT.

Numerous violet-blue flowers, each about ½ inch across, of 5 rounded corolla lobes joining in a funnel-like tube, are clustered into a head about 2½ inches in diameter, which nods slightly on its erect stem. Plants are about 8 inches high, with numerous bright-green, pinnate leaves cut into many narrow leaflets. The leaves may be erect or may interweave somewhat at the base of a close group of several plants. Grows in rocky places, alpine zone. Blooms late June-early July.

The sky pilot, growing among rocks up where the sky seems very near, reflects its blue and so is supposed to direct our thoughts upward. This same feeling is embodied in the name of another species of _Polemonium_, Jacobs ladder, _Polemonium pulcherrimum_, the staggered leaves of which may represent the steps by which we climb. Sky pilot seems very much affected by the particular season. In a dry summer, it is straggly and manages to produce only a few blooms of faded blue. In a good year, large clumps of sturdy erect plants make patches of deep color, accented by their golden stamens. The leaves have a strong, offensive odor, but the flowers are honey sweet.

Phlox Family
Scarlet Gilia, _Gilia aggregata_, SPRENG.

Individual flower, 1½ inches long, is formed of a slender trumpet-like, bright-scarlet (sometimes coral pink) corolla flaring at the mouth into 5 narrow lobes. Numerous flowers attached by short pedicels, are carried in small groups along one side of the green stem. Plant is about 18-24 inches tall, usually of one main stem, with sometimes a few branches. Leaves are deeply cut into thin linear subdivisions, usually curved. Grows in plains and foothills zones. Blooms June-August.

In many otherwise barren areas, the red gilia or sky rocket plant spreads its blaze of color in large patches or hangs, a single wand of bloom, over the edge of the trail. It keeps blooming through the summer, a few stragglers holding on till Labor Day. In early September we have found them in the Wet Mountain Valley brightening the brown of the autumn grasses. A white species, _Gilia attenuata_, tends to grow at lower elevations—the red higher in the foothills. The pale pink and coral plants are probably hybrids.

Figwort Family
Indian Paintbrush, _Castilleja integra_, GRAY

The true flowers are slender, two-lipped tubes of pale or greenish color about 1 inch long. They are surrounded and often completely hidden by the conspicuous, brick-red, modified leaves (bracts) which form a flower-like cluster at the upper ends of the stems. The bract colors in this species vary considerably through several shades of red. Plant is 8-15 inches tall composed of several leafy stems, very tough and woody at their lower ends, rising from a woody root crown. Grows in foothills and higher plains, extending upward through montane zone. Blooms June-July.

In the early summer, this spectacular plant may be seen in the prairie stretches along the highway between Denver and Colorado Springs—or a bit later in the season—literally carpeting the drier areas of South Park. In higher altitudes, particularly in the well-watered vales of Engelmann Spruce, there are other species with bracts of brilliant shades of rose and maroon. In those same high gardens and on above timberline there is a yellow paintbrush. The fortunate flower hunter may even be rewarded by a yellow one tipped with red—or red edged with yellow.

Figwort Family
Penstemon, _Penstemon unilateralis_, RYDB.

Individual flower is about ½ inch wide and somewhat longer, formed of a bell-shaped, lavender-blue corolla which flares at its mouth into 5 lobes separated into two groups. Numerous flowers, in groups of 3 or more, are closely arranged along one side of the top half of each stem, several stems rising from a root crown. Plant is 2 feet or more tall, with narrow tapering leaves, opposite each other in pairs. Grows in foothills and montane zones. Blooms late June-July.

This is but one of twenty or more species of Penstemon found in Colorado. Some, such as _Penstemon angustifolius_, with its azure blue flowers, grow on the plains. A few are dwarf species of the sub-alpine zone such as _Penstemon harbourii_. Every zone and every section has its quota, and they range in color through all shades of lavender, blue, purple, and even red. In details of flower structure, as well as in size, they vary considerably. All of them, however, have a tubular corolla of some shape, terminating in five lobes, divided into two groups, giving them a two-lipped appearance. From this their relationship to garden snapdragons is apparent. In the penstemons, also, the topmost of their five stamens is sterile and often tipped with a little brush of hairs. This gives them the name of beardstongue.

Composite Family
Gaillardia, _Gaillardia aristata_, PURSH

Flower head, 3 inches or more across, is formed of a central red disk made up of many minute tubular flowers (florets), surrounded by an outer circle of long flat golden rays cleft at tips into 3 teeth. Plants are 2 feet or more high of several rough stems usually erect, but sometimes contorted. The dark green leaves are lance-shaped and rough. Grows in foothills. Blooms June-July.

Do you have one just like this in your garden? Cultivation has changed the gaillardia less than it has most native plants. It was born a handsome, showy flower. There is charm in its notched rays and in the way the red of the central disk flowers runs outward into the gold of the rays, as though the painter had been careless with his brush and lavish with his colors. It grows far beyond the limits of Colorado. In the rough breaks of the Montana hills several separate plants will spread out and interweave as a colorful mass, giving it there the name “blanket-flower.”

Composite Family
Rabbit Brush, _Chrysothamnus nauseosus_, H. AND C.

Individual flower heads are about ¼ inch across and double that in length, each formed of a dozen or more tubular bright gold florets closely compressed at their bases into a green involucre. Numerous such heads are clustered loosely together into round-topped groups (cymes) at the ends of stems and branches. Plant is a wide-branching, woody shrub 2-4 feet high with small, green-gray, linear leaves. Grows on dry plains and lower foothills, especially common in western Colorado. Blooms September-October.

Most of the better known composites have spreading rays—each of which is really a flower, though usually sterile—surrounding a disc of less conspicuous tubular flowers, these latter being normally the fertile ones. Sunflowers are familiar examples. Throughout some genera of this great family, and in various species of additional genera, the rays are totally absent. Rabbit brush is one of the composites whose flower heads have no rays. They are showy only because so many of them cluster together, and because each small flower contributes a speck of bright gold. They are distinctly plants of desert lands, and in the fall season each big clump is a perfect mound of color. As winter nears, the color pales and fades, though flowers hang on a long time. Rabbit brush is not a sagebrush, even though both grow on the same dry plains and both are members of the composite family.

Composite Family
Easter Daisy, _Townsendia sericea_, HOOK.

Flower heads, 2 inches across, are formed of about 30 white rays, slightly striated and indented at the tips, surrounding a disc, about ¾ inch in diameter, of numerous tubular gold-colored florets. Plant is about 3 inches high and carries one or several flower heads right on the top of a spreading tough root crown from which also rise numerous, narrow, linear leaves about 2-3 inches long. Grows on grassy plains, and foothills. Blooms April-May.

These are among the very earliest of the plains flowers. Their typical occurrence is as isolated plants, one here and one there between grass turfs in areas of rather tight prairie sod. They are so low and compact that they are not easy to find, even though their beauty well justifies the search. Spring has come when Easter daisies are out, even though the plains are still clad in winter gray with only a faint suggestion that in time the range will be green. Several other members of this daisylike genus are found in the foothills and plains. One of the commoner of these, _Townsendia eximia_, is easily distinguished by its short spreading branches which carry a few leaves.

Composite Family
Showy Fleabane, _Erigeron speciosus_, C. FONG

Flower head, 1½ inches across, is composed of about 200 narrow rays of brilliant lavender color, surrounding a button-like center ½ inch in diameter, of numerous, bright-gold, tubular florets packed closely together. Plant is 1½ to 3 feet high, freely branching, with numerous flower heads; leaves oblong or oval 2-3 inches long. Grows in shady places, rich moist soil, montane and sub-alpine zones. Blooms late July-September.

As the season advances, these aster-like flowers become the most conspicuous color notes in our high-altitude aspen groves. They come after early flowers are gone and bloom with a profusion unknown to most shade-loving plants. Before they too are gone a leaf here and there on the geranium plants in these same places will have turned bright red; on the ground, ivory colored puff-balls will be ready to discharge their clouds of brown spores, and the very first of the aspen leaves will have turned yellow and be drifting down. Showy fleabanes may linger to catch the first fall snows. Another of the many members of this genus, _Erigeron trifidus_, grows on the plains and brings out its small white blossoms in late April when it may catch the last spring snows.

Composite Family
Alpine Sunflower, _Hymenoxys grandiflora_, PARKER

Flower head is 3 to 4 inches across, the central disk, an inch in diameter, made up of over a hundred tiny, tubular, golden florets, surrounded by about 30 bright yellow rays which are flat and notched at the outer end. Plant is 5 to 15 inches tall of one or several woolly stems, with leaves divided into several narrow lobes. Grows on alpine slopes. June-July.

This woolly-stemmed, dwarf sunflower, sometimes called old-man-of-the-mountains, or sun-god, is a startling surprise for the newcomer to our above-timberline tundras. One expects smaller more timid flowers here, and so at first the big bright faces of these plants seem out of place. Then we come to love them for their gay defiance of tough growing conditions and think of them as the proper guardians of high windy places. Whole colonies of them will be found with all the flower heads faced in the same direction. This will be a direction from which they receive strong light, and is a form of heliotropism. The stems, however, do not twist through a full half circle each day to follow the sun.

Composite Family
Thistle, _Circium undulatum_, SPRENG.

Flower heads, 1½ to 2 inches broad, are solitary at the ends of stems and branches, and made up of numerous (100 or more) rose-colored, tubular florets fluffing out widely at their tops and grouped tightly together at their bases into an involucre made of many little, overlapping green bracts. Plant is about 3 feet tall with gray-green deeply cut leaves; stem and leaf ribs armed with prickles. Grows on plains, extending into foothills. Blooms May-September.

Thistles of some sort are found in all parts of Colorado. Above timberline they take on grotesque shapes. In one, high-altitude thistle, _Circium hookerianum_, the whole woolly top of the plant, formed of compressed leaves and inconspicuous flower heads, bends over to resemble the head and neck of some shaggy animal. In our sub-alpine hay meadows a different species, _Circium drummondii_, may spread flat on the ground with no main stem and keep its flower heads so low that the mowing machine goes right over it catching only tops of a few leaves. On the plains are other species with shaving-brush-like flower heads. In spite of the prickles on their leaves and stems, horses nip off the flower heads and eat them with relish. Donkeys and mules seem to like them even better.

CLASSIFICATION OF PLANTS

All plants are related to each other in the sense that every one of them is descended from a common primitive uni-cellular life form which came into existence on this planet millions of years ago. As the remote progeny of that ancestral cell, or group of cells, became scattered over the earth and faced diverse conditions, which in turn changed with the ages, these millions of related organisms exhibited profound changes such that the differences in form, size and structure have become more noticeable than are the badges of common inheritance. This is the process called Evolution. Changes are established so slowly, however, that the immediate descendants of any particular plant, or the offspring from cross-pollination within a closely related group, will continue for many generations to be substantially identical in structure with the parents. As long as substantial identity in structure exists, all of these individual plants form a single “species.” As these species are discovered, botanists give each of them a Latin name. Within Colorado over 2000 such separate species of flowering plants are known. Minute variations such as color of petals or degree of hairiness of leaf or stem are treated as “varieties” within the species.

Many thousands of these substantially identical plants may be found scattered over parts of a state, or over several states, or even throughout a life zone area comprising parts of several continents. Within the life zone favorable to them, the only geographical limits seem to be those affecting distribution of live seed.

In the search for plants, many different species are found, either in the same or more often in different localities, in which the resemblances are close; in fact many parts are almost identical, but persistent differences are also present. A common ancestor several hundred or several thousand years back may have existed, but evolutionary changes have brought noticeable differences in the respective descendant groups. If the changes are not too great, especially if the mechanisms of reproduction have not been so greatly changed as to make cross-pollination totally impossible between plants of the several species, these related species, wherever they may have been found, are said to comprise a “genus.” To this, also, a Latin name is given. _Lillium_, for example, is the generic name of all true lilies everywhere; _umbellatum_, however, is the specific name of the group to which our Colorado mountain lily belongs; and “_Lillium umbellatum_” is the full name of the plant shown on page 10.

Still greater differences in plant and flower structure are found, coupled, however, with strong resemblances in significant parts of the structure. This has led to grouping a considerable number of genera together into a “family.” Latin names also are given to the families. For these names there are, in most cases, well established English equivalents which we have used here without repeating the more technical family name. Within each family all genera and each species of every genus will exhibit strong resemblances in the mechanism of seed production, and the general pattern of the organs of reproduction will be recognizably similar. For example, all species in the rose family (with very few exceptions) have numerous stamens arranged in whorls; they also have a calyx formed of five sepals joined together at the base.

Other groupings, such as “Orders” comprised of several families, or “tribes” composed of several genera within a family, are used by botanists, but for the purposes of this booklet we have used only the names of families, genera and species.

To the amateur one of the most interesting phases of plant classification is the way in which, as we pass from one life zone to another, or from one part of the state to another part within the same life zone, we find that a plant species which we have observed at one spot, is replaced, at another, by a different species within the same genus. We find our white mariposa, _Calochortus gunnisonii_, on the east side of the mountains, then, in flat clay plains in southwestern Colorado, we find the sego lily, Calochortus nuttallii, which is a similar, but quite distinct mariposa with cream-colored petals and a crooked, much shorter stem. Beyond the boundaries of Colorado numerous other species of Calochortus are found, all of them different from ours, but all of them quite obviously mariposas.

HOW PLANT POPULATIONS MAINTAIN THEMSELVES AND SPREAD

Infant mortality is high and life expectancy short among the flowering plants. They not only struggle against extremes of climate, but they are the primary food of the animal kingdom, and so pursued by creatures that have the advantages of sight and locomotion. It is only by marvelous fecundity and by ingenious devices for seed dispersal that plants maintain their position on the earth.

The first objective of every plant is to produce fertile seed in as large a quantity as the supplies of food and moisture and the length of season will permit. Pollination, which brings about the merging of the male and female cells, is essential to seed production. The majority of plants combine in a single flower stamens which carry in anthers on their tips the male element pollen and one or more pistils which hold at their base ovaries containing the female cells. These ovaries are reached by the pollen through the style and the stigma at its tip. The flower may thus fertilize itself in most species, but cross-pollination from other plants of the same species makes for more vigorous stock. The showy petals and petal-like sepals, which draw our eyes to flowers, make the flower conspicuous also to bees, moths, and even birds which act as pollen bearers. Other lures to this same end are fragrances and nectar. The detailed mechanisms by which the various plants increase the likelihood of cross-fertilization, within the brief period that any given set of cells is capable of fertilization, are numerous indeed and a fascinating study.

In most plants, seed develops and becomes fully ripe in a matter of weeks after fertilization has occurred. It is also commonplace for a single flower to produce a seed pod or other fruit which may contain hundreds of separate perfect seeds.

The next step is to scatter this seed over an area wide enough to reduce the risk of all of them perishing at once, and also wide enough to keep the survivors from competing too closely with each other for soil, moisture and sunlight. Here again fascinating devices come into play. Building each seed with a plume or bit of fluff at its tip so that it can be carried far by wind, is one of the commonest tricks. Other seeds float easily on water and so reach new sites. Other seeds invite being eaten by birds or beasts, and depend upon a fraction of them either being carelessly dropped before being swallowed, or having tough enough shells to resist digestion. Quite a number of plants produce seed pods which, when they become thoroughly dry split open with a jerk flipping seeds over distances of several feet. Finally there are the various burs and barbed seeds that are carried for miles by animals and by man.

Seeds thus become scattered over the earth, and so numerous and efficient are the devices of dispersion that in the course of years the seeds from a single plant colony, and from the successive new outlying colonies it founds, may become spread over miles of distance. Only a few barriers completely stop such spreading. Oceans, high mountains and broad deserts are the most effective barriers, but even they do not always stop every seed of every plant.

This spread of seeds pays little attention to life zone limits, or to such interference as rivers, hills or local barren areas may present. Over and past all of such minor obstacles the flow of seed rolls.

The final problem for the seed is how to germinate and become established in the place it lands. If that place is totally unsuitable for the particular species, the answer there is failure. Many seeds may invade a locality too dry for their development. In such a case, even if germination occurs, all such seedlings will die before a single plant matures. Heavy frost may act as a like absolute veto to other seedlings that venture too high in altitude or too far north in latitude for their own limitations. By forces such as these, each species of plant stays contained within limits beyond which it cannot become established, even though individual seeds may in great numbers invade impossible localities.

Mature plants may tolerate conditions which wipe out all tender seedlings of the same species. This leads to interesting patterns of plant distribution in semi-desert areas, such as occur in parts of Colorado. Once or twice in a century a series of two, three, or even five successive years may occur when the soil is moist and extraordinarily favorable to plant growth throughout weeks or months of the spring and summer. In these special times seeds that have invaded a usually hostile area may, if they have retained fertility, germinate, push their roots deep, and become so vigorous that when normal dry years follow these particular plants live on and thrive for the remainder of their lives, even though their own seeds fall on barren ground and the species maintains only a precarious or temporary foothold in the area.

Governed by forces such as these, and limited by competition with each other, plant species have for ages taken their places in the global economy and carried out their part of the commandment to be fruitful and multiply. Otherwise we and the animals we prey upon could not exist.

FLOWER FORMS

The four flowers sketched below with supplementary drawings of their separate parts, give only a small sample of the infinite structural variety found among flowering plants.

perianth segment
stigma
anther
style
ovary
pedical
stem
Detail of stamen
pollen
anther
filament

group of styles
sepal
group of
stamens
ovary
pedical
single sepal
Detail of stamen

lobe of corolla
sterile stamen
anther
stigma
style
sepal
ovary
calyx
pedicel
Details
beard
filament
anther
filament

(right half cut away and all other florets removed)
bracts of involucre
tubular floret
receptacle
ray floret
stigma
style
stamen
corolla tube
ovary
receptacle

PLANT PARTS

pedicel
stem

pedicel
bract
scape

stem
bulb

stem
root crown or caudex

main stem
tap root
root

scape

LEAF FORMS

linear
lanceolate
ovate
cordate

pinnate
pinnately
cleft
bipinnate
palmate

opposite
alternate
whorls

stem
petiole
stipule

BOOKS DEALING WITH COLORADO WILDFLOWERS

Field Book of Western Wild Flowers—Margaret Armstrong
C. P. Putnam’s Sons, N. Y., 1915

Plants of Rocky Mountain National Park—Ruth E. Ashton
Government Printing Office, 1933
Revised edition under same title—Ruth Ashton Nelson in press, 1953

Colorado Cacti—Chas. H. Boissevain and Carol Davidson
Abbey Garden Press, San Marino, 1940

Rocky Mountain Flowers—Frederic E. and Edith S. Clements
H. W. Wilson Co., N. Y., 1920

New Manual of Botany of the Central Rocky Mountains—John
Coulter and Aven Nelson
American Book Co., Chicago, 1909

Manual of the Plants of Colorado—H. D. Harrington
Sage Press, Ft. Collins, Colorado—in press, 1953

American Wild Flowers—Harold N. Moldenke
D. Van Nostrand Company, Inc., N. Y., 1949

Meet the Natives—M. Walter Pesman
Denver, Colorado, 1943

Flora of Colorado—P. A. Rydberg
Ft. Collins, Colorado, 1906

Flora of Rocky Mountains and Adjacent Plains—P. A. Rydberg
New York, 1917

The Flora of Boulder County, Colorado—William A. Weber
University of Colorado Museum

OTHER MUSEUM PICTORIALS

1. Nature Photography with Miniature Cameras—Alfred M. Bailey

2. The Story of Pueblo Pottery—H. M. Wormington and Arminta Neal

3. Stepping Stones Across the Pacific—Alfred M. Bailey and Robert J.
Niedrach

4. Fossil Mammals—Harvey C. Markman

5. Nature Photography with High-Speed Flash—Walker Van Riper, Robert J.
Niedrach and Alfred M. Bailey

6. Laysan and Black-footed Albatrosses—Alfred M. Bailey

7. The Hawaiian Monk Seal—Alfred M. Bailey

INDEX

A
_Page_
_Abronia fragrans_ 14
Alpine forget-me-not 46
Alpine sunflower 55
_Anemone globosa_ 20
_Aquilegia coerulea_ 24
_Argemone intermedia_ 25
_Asclepias speciosa_ 43

B
Bird-bill 41
Brook primrose 40
Bush cinquefoil 29
Bush morning-glory 44