Spring ephemerals are plants that emerge, bloom, produce seed, and disappear all within a matter of weeks. These plants employ fascinating survival strategies to get a jump-start on other species or to overcome tough conditions. Like other so-called "charismatic" species, many spring ephemerals also have a long, complicated history with humans. They have both benefited and suffered from appealing to human sensibilities. That many New Yorkers associate spring with tulip and daffodil displays is a testament to the extensive role humans have played in breeding and dispersing these plants. For those who know where to look, our local woodlands offer displays of wild ephemerals that rival any planted display. Many of these northeastern species are becoming more popular in the horticulture world. As tastes change, we have an opportunity to help these plant populations grow by planting them in gardens. However, anytime we interfere with wild species we must be mindful of unintended consequences.
Familiar ephemerals like tulips ( Tulipa sp.) and daffodils (Narcissus sp.) evolved in radically different conditions than those experienced by our local woodland species. The sweet faces of tulips and daffodils belie their tough natures. Though we often associate such plants with the cool pastures of the Netherlands, many originally evolved in harsh, dry climates in the Mediterranean, Middle East and Central Asia. Storing energy in underground bulbs enables these plants to go dormant during seasons of heat, drought, and high winds. Both tulips and daffodils store energy in their bulbs, which, like onions, are comprised of layers of modified leaves. The plant's aboveground leaves emerge, and through photosynthesis, produce sugars that are stored away underground. The plant quickly saves up enough energy that it can go dormant before heat and drought set in. Even more impressive, daffodils have contractile roots that can pull them deeper into the soil if conditions near the surface become unfavorable.
Our native spring ephemerals evolved in moist woodlands where they do not need to beat summer heat and drought, but rather race to catch the sunlight before the trees leaf out. By the time the canopy shades the forest floor, these ephemerals have already generated enough energy to flower and set seed. Some of these species have developed a particularly clever strategy for seed dispersal. Trilliums ( Trillium sp.), twinleaf (Jeffersonia diphylla), and trout lily (Erythronium americanum), among others, attach fatty appendages called "elaiosomes" to their seeds. Ants (and sometimes wasps and daddy long-legs) seek out this nourishing fat and carry the seeds away from the parent plant. Most Northeast ephemerals also reproduce vegetatively by sending out new shoots from their underground storage organs (which take a variety of forms including bulbs, rhizomes, tubers and corms). In this way, colonies of clones can form rapidly from a parent plant. Though reproduction through seed remains important for genetic diversity, vegetative reproduction is especially important for species resilience because it's a much faster process.
In the wild, many plants depend on animals for pollination and seed dispersal. The shapes of flowers often reflect the pollinators that visit them. For example, shooting star ( Dodecatheon meadia) relies on bumblebees to perform "buzz pollination." To shake out the pollen, the bee clings to the downward pointing tip of the flower and vibrates against it at a certain frequency.Because of their unique shape, shooting star (Dodecatheon meadia) flowers can only be fertilized through "buzz pollination".
Though flowers evolved to attract insect pollinators, not humans, human fascination with floral beauty has played a pivotal role in both how plants look and where they grow. When enchanted by a plant's beauty, flavor or scent, humans may take over the roles normally filled by other animals. Ephemerals like tulips, grape hyacinths ( Muscari sp.) and daffodils have been planted around the world by gardeners who love their beautiful spring presence and their way of politely disappearing by summer. For a plant, appealing to human sensibilities can be the key not only to surviving, but to spreading. As the writer, Michael Pollan points out, "For a flower the path to world domination passes through humanity's ever-shifting ideals of beauty."
Though we are centuries removed from the Dutch tulip craze, human desires for particular aesthetics continues to impact many species of ephemerals. Like tulips, our native trilliums ( Trillium sp.) are a favorite of gardeners on the hunt for unusual specimens. A disease that alters the patterning of the flower, but ultimately kills the plant also affects trilliums. Such anomalies can fetch over $100 per individual plant. By distributing these infected individuals, gardeners help the disease more than the plant.
Like many of our spring ephemerals, trilliums take years to mature from seed. As these plants become more sought-after commodities, wild populations become vulnerable to unscrupulous trade practices. Because these plants are expensive to produce in the nursery, some sellers have taken to digging them up in the wild and selling them at a lower price. Though native spring ephemerals make wonderful additions to the garden and getting a deal on them may be tempting, our first priority should be protecting wild populations of these plants.
Human ideals of beauty still play a huge role in the survival, spread and physical appearance of spring ephemerals. As we know from tulips, cultivated plant varieties are not necessarily stronger or better adapted to their environments than wild species because plant breeders have often been more concerned with the look of the plant than its other attributes. As the naturalistic aesthetic becomes more popular in gardens, we have the opportunity to work with more wild, native species that are suited to our local environmental conditions. When we plant wild spring ephemerals we have the chance to appreciate the full character of the plant, not just its appearance, but also how it interacts with its environment.
For the 2018 season, the High Line is celebrating the floral character of spring. RSVP for one of our Celebrating Spring Ephemerals tours, guided by a High Line gardener.
Celebrating Spring Ephemerals is made possible, in part, by TD Bank—the Presenting Green Sponsor of the High Line.