If you are a hawk moth you pollinate an eastern prairie fringed orchid on a soft, warm night in early July by hovering in front of it and inserting your long proboscis past the sexual organs of the flower and deep into the long spur that hangs from the rear of the blossom. A pool of nectar as much as a centimeter deep awaits you there, and as you suck up the sugary syrup, the pollinium, the little packet of pollen in the flower, attaches itself to the side of your proboscis. When you probe another flower the pollinium will attach itself to the stigma of that bloom, allowing the pollen to grow into the ovary and fertilize the ovules there.
If you are a human being you pollinate an eastern prairie fringed orchid by searching through likely habitat on a hot day in early July carrying a stack of Styrofoam cups and a box of toothpicks. If you find an orchid in flower you get down on your hands and knees in front of it and insert a toothpick into one of the blossoms. The pollinium sticks to the toothpick. You place an upended cup on the ground and insert the free end of the toothpick into the cup's bottom. When you have finished removing the pollinia from the dozen or so blooms on the average orchid, your cup is crowned with a little palisade of toothpicks.
You find another flowering stalk and repeat the process. Then you carefully insert the pollinated ends of the toothpicks from the first plant into the blossoms on the second plant, one at a time, and allow the pollinia to attach themselves to the stigmata in each blossom. Then you take the pollinia from the second plant and insert them, one at a time, into the flowers on the first plant.
Somehow the way the moths do it sounds like more fun. Of course we humans are capable of having fun once removed. Even the most arduous task can become a source of joy and satisfaction if we can honestly tell ourselves that the work is doing some good. This year a group of about 20 Chicago-area volunteer human pollinators got a chance to tell themselves exactly that.
They were working on one phase of a recovery plan for the eastern prairie fringed orchid, Platanthera leucophaea, a plant that has fallen on such hard times that it is listed as endangered in Illinois and threatened nationwide. It didn't use to be a rarity. It grows across a fairly broad segment of the moisture gradient, showing up occasionally right in the middle of the gradient in mesic prairies. It is most common in wet-mesic and wet prairies, but it can also be found in the even wetter sedge meadows and fens.
All of these habitats used to be widespread in northern Illinois, and it seems likely that our area was the heart of the plant's historic range. You can still find eastern prairie fringed orchids in Michigan, Ohio, Wisconsin, and southern Ontario. West of the Mississippi the western prairie fringed orchid--the two were thought of as a single species until recently--takes over.
Illinois has 21 known populations of the orchid, more than any other state. Michigan is the runner-up with 14. Eighteen of Illinois' sites are in the northern part of the state.
The recovery plan for the species was drawn up by Marlin Bowles of the Morton Arboretum. Its major emphasis is on management of sites where the orchid now grows to improve conditions for the species. The measures recommended are familiar practices on prairies and wetlands around here: keep brush out, control exotics like purple loosestrife, burn from time to time, keep the deer population within reasonable limits. It is a regime that is likely to benefit the entire native plant community.
On some of the sites management will be handled by members of the Volunteer Stewardship Network. The state Department of Conservation is doing major management work on sites it owns. If these efforts have their expected effect, the existing 21 populations will be vigorous, healthy, and able to sustain the species for some time.
But wouldn't it be nice if we could establish more populations? What if we could saturate northern Illinois with eastern prairie fringed orchids? We live in an area where the art of ecological restoration is entering a golden age. Thanks to the efforts of our restorationists, we have more potential sites for this plant than we did ten years ago, and each year adds to the list. Why not spread the orchids so widely that we can take them off the lists for good?
This is where the two-legged hawk moths come in. Back in 1981 Steve Packard of the Nature Conservancy hand pollinated some eastern prairie fringed orchids on a site along the North Branch of the Chicago River. The plants produced abundant seed, which he scattered on the site. Five years later--it takes that long for the orchids to mature--the plants that grew from the seeds he scattered produced flowers.
That experience provided the basis for a small grant from the U.S. Fish and Wildlife Service to the Nature Conservancy for a joint project to help restore the eastern prairie fringed orchid. The project would use volunteer labor to hand pollinate the plants in July. The volunteers would return in late September and early October to gather the mature seed capsules. The seeds would be scattered either on the same site or in a new location.
It is not a wild exaggeration to say that this kind of project could happen only in the Chicago area. The Volunteer Stewardship Network and all its associated restoration efforts along the North Branch of the Chicago River, at Poplar Creek, in the Palos area, around the Sand Ridge Nature Center, and at dozens of other places have created an army of hundreds--perhaps thousands--of dedicated, knowledgeable field botanists. Chicago is a place where a discussion of the ecology of prairie grasses can fill a college lecture hall with 300 schoolteachers, mail carriers, dentists, and carpenters, all of whom will understand every word that is said--including the long strings of scientific names. Scientists who come from elsewhere to give talks in Chicago are always amazed to encounter this level of knowledge and enthusiasm among laypeople.
Amelia Orton-Palmer, an endangered-species biologist with the U.S. Fish and Wildlife Service office in Barrington, talks of the "incredible commitment and knowledge" of the local volunteers. "This area is really special in that regard. The citizenry is really tied in."
The tied-in citizens who pollinated the orchids in July are now out collecting the mature seed capsules. According to Marlin Bowles, leaving the matter entirely to the hawk moths would result in pollination of about half of the 12 or so flowers on each plant. Hand pollination approaches 100 percent. The reproductive strategy of orchids involves producing very large numbers of very small seeds. Each flower produces a capsule that contains as many as 5,000 seeds.
Part of the high-powered scientific equipment provided for each volunteer--along with the toothpicks and Styrofoam cups--is a small white bowl. The volunteers are instructed to count out 25 tiny seeds into the bowl and eyeball the 25 so they know what 25 seeds look like. Then they can pick up approximately that number, one pinch at a time, and scatter them.
Some of the capsules will be tied to tall grass stems with gray thread (more sophisticated scientific equipment--of course if the Pentagon were buying this stuff the thread would cost $100 a foot). As the capsule deteriorates, the wind will carry the seeds away just as it would if the capsule were still on the orchid.
So far the seeds have been dispersed to 17 sites. Most of these either have populations or have had populations in recent times. All are protected sites where active management will give the orchids a reasonable chance of survival.
No one knows yet whether the orchids require special mycorrhizal fungi to thrive. All plants enter into symbiotic relations with fungi that live on their roots. Most of these mycorrhizal fungi can spread their spores without any aid. But if the orchids require something special, the seeds will need to be mixed with soil from places where the plants already grow. Marlin Bowles is currently examining this question.
The outcome of this project will only begin to be revealed five years from now, when this year's scattered seeds begin to produce flowers. Until then our two-legged hawk moths will be out in July with their toothpicks.