An Odd Mix of Spring

Out back last evening, it looked, felt and smelled like late April. The lilacs and honeysuckle were in bloom, dandelions and violets speckled the lawn and the trees were nearly leafed out; even the late-leafing sycamores and black walnuts had a modest canopy of green. Toads were trilling, honey bees buzzed across the flower beds and a band of thunderstorms loomed to the west.

Yet, there were missing pieces to this late April scene. While our permanent avian residents moved about the yard, they were still joined by wintering juncos and white-throated sparrows. Many other birds, usually present in mid spring, were conspicuous by their absence; there were no chimney swifts in the evening sky, no house wrens singing in the twilight and no gray catbirds scouring the shrub line. Colorful warblers were not flitting about the shade trees and no northern orioles or indigo buntings had arrived to compete for attention with our resident cardinals and blue jays.

While plants, amphibians, reptiles and hibernating mammals have responded to the exceptionally warm spring and are well ahead of their usual spring schedule, migrant songbirds are attuned to the light cycle and will leave their winter haunts at the same time each year, regardless of the weather up north. After all, awaiting their departure from Mexico or the Gulf Coast, they have no clue that the Midwest landscape is well ahead of schedule, a product of summer-like warmth. They will arrive when they usually do and our winter residents will depart in concert; whether either group will take heed of the altered landscape is something we'll never know.

Pleistocene Plant Revival

A recent article in the New York Times reported on the successful revival of a narrow-leafed campion from deposits of the late Pleistocene. Russian paleontologists had discovered seeds and fruits of the plant in river bed sediments of eastern Siberia, apparently buried by a ground squirrel; radiocarbon dating of the seeds indicated that they were first entombed about 32,000 years ago, when humans were displacing Neanderthals in Europe and Denisovans in eastern Asia.

While efforts to germinate the seeds were unsuccessful, the scientists were able to thaw and culture placental cells from the fruit, yielding mature plants that flowered and produced new seed; these descendent seeds were then planted to yield another generation of campions. According to the article, the Russian scientists speculate that the Pleistocene plant material was buried in soil just above the permafrost layer, favoring its prolonged viability; in addition, sugars and phenols within the plant tissue served as an antifreeze, protecting cellular structure.

Though this story focuses on what appears to be a record for ancient plant revival, it says more about the nature of life itself. Rather than some mystical or spiritual property, life is a physical process, requiring just the right biochemistry and environment in which to flourish. Governed by DNA and coordinated by neurovascular networks, the stem cells of life give rise to complete organisms and, as this event revealed, may do so after long periods of dormancy. We humans are just beginning to understand the potential benefits of this knowledge and, if not derailed by the forces of religious mysticism, stem cell research will play a major role in the future of agriculture and health care.

Crocus Days

The crocuses have been blooming in Columbia over the past week, a bit ahead of schedule due to our mild winter. Their appearance, together with that of other early bloomers, such as snowdrops, periwinkle and hyacinths, is always a welcome sight, indicating that the depth of winter has surely passed.

Nevertheless, these precocious flowers signal the onset of an annual period during which the weather is especially challenging across the American Heartland. Here in Missouri, we enter the gray, damp, raw days of late winter and early spring, characterized by wet snow, cold rain and a muddy landscape. And out west, at our Littleton, Colorado, farm, we face the heaviest snowfalls of the year as the upslope storms of March and April descend on the Front Range.

Like the arrival of snow geese and the frenzied calls of chorus frogs, these crocus days are bittersweet, an early sign of spring but a reminder that the sunny, mild, heart of the season is still a month or more away. Until then, we impatient humans will rely on the spectacle of waterfowl migrations, the greening of our landscape and the growing intensity of birdsong to balance the gloomy days and sloppy terrain.

Common Mullein

Driving through the American countryside, especially across semi-arid grasslands of the West, one readily concludes that common mullein is native to North America. Yet, this widespread plant, easily recognized by its tall, flowering stalk, is native to Eurasia and North Africa; it was introduced to America by European colonists in the early 1700s and was initially culivated for medicinal purposes.

Favoring abundant sunshine and well-drained soil, common mullein is a biennial, requiring two years to complete its life cycle. Following germination, the plant forms a rosette of large, velvety leaves which persists through the following winter; as the second spring progresses, a tall stalk is produced (often rising 6 feet or more) on which numerous, compact, yellow flowers develop. These flowers, which bloom in sequence from late June through mid September, are pollinated by bees, other insects or wind currents; an abundant crop of tiny seeds, eaten by goldfinches and buntings, remain on the drying stalk through the winter and are eventually scattered by the wind. Able to survive long periods of dormancy, mullein seeds are programmed to await ideal growing conditions and may not germinate for decades.

Like other prolific aliens, such as dandelions and starlings, common mullein owes its success in North America to the human tendency to manipulate natural ecosystems. Once introduced into a new environment, the reproductive potential of alien species is often impossible to contain and, to the chagrin of gardeners, farmers and ranchers, they become naturalized "weeds or pests". Since common mullein is clearly here to stay, we might as well enjoy the seasonal beauty of these tall, sun-loving plants.

The Suburban Hibiscus

As the color of spring and early summer begins to fade and the greenery looses its luster, Hibiscus syriacus, commonly known as Rose of Sharon, begins to bloom, adorning the suburban landscape through early autumn. Late to leaf out in the spring, this Asian shrub produces large, showy flowers after most cultivated plants have already gone to seed.

Favoring full sun or partial shade, this plant is drought tolerant and thrives in the dry, sunny climate of the Front Range; we have multiple cultivars on our Littleton farm, with flower colors ranging from white to pink to light blue. Beyond providing a colorful display, the flowers of Hibiscus syriacus attract hummingbirds, butterflies and other insects, and are thus especially appealing to the backyard naturalist.

Seed pods, which overwinter on this shrub, contain numerous, fuzzy seeds that, in moist, warm, climates, can be a nuisance, yielding a forest of seedlings each year; this is less of a problem in more northern or semiarid regions, where the seeds are more likely to be consumed by wildlife than to germinate. Of course, for those of us who prefer wild borders to manicured fencelines, natural proliferation is never a concern.

The Nature of Bamboo

Though often referred to as bamboo "trees," these widespread plants are actually members of the grass family. Represented by more than 1400 species across the globe, bamboo is most abundant and most heavily utilized in southern and eastern Asia; however, native species grow on all continents except Europe and Antarctica. North American bamboo, known as river cane or canebreak, was once common from the Chesapeake Bay to the Ohio River Valley and southward to the Gulf Coast; scattered pockets remain but most stands have been cleared for agriculture.

Initially sprouting from seed, bamboo spreads via underground rhizomes, resulting in large, dense colonies of genetically identical plants; most species are found in tropical areas but some are cold tolerant and grow in the Temperate Zone. Flowering and subsequent seed pod production occurs simultaneously throughout the colony but such events are often widely spaced, occuring every 40-100 years or more in the largest species. Smaller species flower more frequently and remain viable while larger bamboos die once their seed pods are produced.

Across the globe, bamboo is used for a wide variety of purposes. Tender stems, leaves and seed pods are eaten by giant pandas, lemurs, cattle, humans and a host of other animals while the mature, woody stems have been used to make paper, straws, pipes, poles, rafts, scaffolding and homes, among a myriad of other products. Since bamboo is one of the fastest growing plants on Earth, it has been increasingly used for livestock feed and may become an important source for biofuels.

Prickly Pear Cacti

Prickly pears, members of the genus Opuntia, are the most widespread and heavily utilized cacti on our planet. Native to the Americas, more than 200 species now grace the globe, many of which are under cultivation for food, livestock feed and a variety of materials.

While most species of prickly pear colonize desert or semiarid life zones, they are found from southern Canada to South America and are the only cacti native to the eastern U.S. Characterized by fleshy pads (nopales) which harbor long, fixed spines and small, fine, barbed glochids, most prickly pears grow in dense clusters, low to the ground; however, some species branch upward to form shrubs or small trees, reaching heights of seven feet or more. Prickly pear flowers, which bloom from April to June (depending on latitude) are most often yellow or orange but may be red, pink or purple in color. Their globular fruit, also coated with glochids, is consumed by birds, rodents, deer, peccaries and other wildife and have been used by human communities to make candies, jellies, juices and coloncha (an alcoholic beverage); the nopales are also edible, mixed into salads or cultivated for livestock.

Vigorous, hardy and fast growing, prickly pears have been used for natural fencing and, in areas without natural predators, have become a threat to native flora. Various parts of these cacti have provided dyes, medications, fiber and a sticky resin, used to make plaster; most recently, prickly pears are being investigated as a potential source for biofuel. Attractive and prolific, prickly pear cacti brighten the landscape while offering many additional gifts to humans and wildlife alike.

The Nature of Yard Work

Despised as just another chore during our teen years, yard work is a favorite activity for many adults. After all, it gets us outdoors, affords plenty of exercise, allows us to reconnect with nature and rewards us with garden foods and the beauty of flowering plants.

Of course, our definition of natural beauty varies and our individual preferences can lead to household conflicts. Some prefer manicured landscapes with broad, uniform lawns, evenly trimmed shrubs, neatly spaced plants and store-bought mulch. Others, myself included, favor limited lawn space, broad, naturalized borders and self-sustaining perennials. Perhaps the primary source of disagreement arises with the decision to use or ban fertilizers, herbicides, pesticides and other products that are marketed to yield pristine, weed-free, insect-controlled lawns and gardens. After all, one must compete with the neighbors.

If you, like most naturalists, want a property with a diverse population of wildlife, it's best to utilize native plants, establish wild borders, minimize lawn space and abolish the use of artificial chemicals. You'll still have enough to keep you busy but you'll have more time to enjoy your wild neighbors and they will benefit from your pollution-free patch of earth.

The Scent of Green

Here in the American Midwest, it is usually mid April when we get our first whiff of freshly cut grass. Often spawned by the efforts of a fastidious neighbor, trying to annihilate the first crop of dandelions, the familiar smell wafts about in the warm, afternoon breeze, confirming the fact that winter has faded to the north.

More than a sign of the season, the odor of cut grass, like that of wood smoke, is sure to trigger memories of our youth; visions of Little League baseball, backyard cookouts and suburban parks all come to mind. Of course, it also conjures up the exasperation of those seemingly endless teenage chores and the hot, muggy air of a Midwestern summer.

While a manicured lawn is both the pride of American homeowners and an affront to nature's sensibilities, the fragrance of grass clippings is welcomed by gardeners and naturalists alike. It is, after all, the scent of green.

Geophyte Season

The appearance of hyacinths and crocuses, in late winter, is a welcome sight to gardeners and heralds the onset of geophyte season in the American Midwest. Geopyhytes are perennial plants that harbor underground, nutrient-storage structures that permit survival during periods of prolonged cold or drought and fuel the rapid development of stems, leaves and flowers when soil conditions recover.

There are three primary types of geophytes: those that produce bulbs, corms or tubers. Bulb plants, including hyacinths, tulips, narcissus, lilies, onions and others, possess a cluster of specialized leaf scales which surround the basal stem and store nutrients. In most species, a protective tunic envelops these scales and, in all species, a basal plate gives rise to the root system. Corms are starchy stem structures which sit vertically beneath the soil; crocuses and gladiolus species utilize this form of nutrient storage. Finally, tubers are thickened, starch-containing, horizontal structures along the roots or stems of certain plants; root tubers are found in dahlias and sweet potatoes while asparagus and strawberries harbor stem tubers.

While natural geophytes respond to local environmental conditions, usually blooming with the recovery from prolonged cold or drought, numerous cultivated species have been developed that provide garden color throughout the growing season. For example, most wild crocuses, native to Eurasia, bloom in the fall while their cultivated cousins ignite the first wave of spring fever here in the Midwest.