Journalist: Zoe Panchen
Photographer: Laura Aschenbeck
A wonderful vista of meadow flowers and grasses unfolded before us as we wandered down an inviting, mown path in the meadow at Bowman’s Hill Wildflower Preserve (BHWP). We paused to marvel at a hummingbird moth beating its wings at lightning speed as it sucked up nectar from a purple bee-balm (Monarda didyma) flower. Amy Hoffmann, Education Coordinator at BHWP and past Longwood Graduate Fellow, encouraged us to touch and smell the plants as we walked through the meadow. “The boneset smells like fruit-loops and used to be used to set bones,” Amy enthusiastically told us. We heard here that the brilliant orange flowers of butterflyweed (Asclepias tuberosa) are a favourite of Monarch butterflies and that there are four types of mountain mint (Pycnanthemum sp.) in the meadow.
Bowman’s Hill Wildflower Preserve, situated on the eastern border of Pennsylvania near the upscale vacation village of New Hope, Bucks County, is celebrating its 75th anniversary this year. BHWP was the brainchild of Mrs. Mary Parry, then Chairman of the Bucks County Federation of Women's Clubs, and Mr. W. Wilson Heinitsh, a Pennsylvania Department of Forest and Waters consultant for Washington Crossing Historic Park. They had a vision to create a sanctuary for native Pennsylvania flora. The Preserve was established in 1934 and now has a mission to lead people to a greater appreciation of native plants, to an understanding of their importance to life and to a commitment to a healthy and diverse natural world.
BHWP is neither a horticultural institution with plants displayed in an orderly fashion, nor is it a nature reserve where plants are grown in a natural environment. Rather, the Preserve presents the plants in a naturalistic setting. The preserve is on land with varied topography and soil types, which has allowed for the establishment of a wide variety of ecological communities. Of the 2000 plants native to Pennsylvania, 800 can be found on the Preserve and 80 of those are rare, threatened or endangered. Amy escorted us along aptly named trails that took us through many of these communities. There was the Fern Trail with 20 different types of ferns, the newly renovated Medicinal Trail with the BHWP emblem plant - the twinleaf (Jeffersonia diphyla) and the Marsh Marigold Trail with skunk cabbage (Symplocarpus foetidus) and the vibrant red cardinal flowers (Lobelia cardinalis). This unique style of plant material display requires a different approach to curation of the Preserve, says curator Dr. Paul Teese. You will not find every plant labelled, just key plants related to a particular trail displayed discretely so as not to spoil the natural setting.
As with many horticultural and natural areas in the region, deer are a big problem. They have destroyed the understory in so many forests, leaving the forest floor bare and with little hope of a succession path for the forest. BHWP has addressed this problem with a 100-acre deer fence in the heart of the 134-acre preserve. The result is lush forest undergrowth and an environment that nurtures rare and unusual plants. Amy pointed out that the meadow is outside the deer fence but that the deer do not disrupt the meadow ecosystem. The deer, she told us, like just one flavour in their mouths at a time and the meadow is too much of a smorgasbord for them. Non-native invasive plants comprise an even larger problem but a 5 year burn cycle and the judicial planting of native species is an effective control method.
Amy introduced us to the Nursery Manager, Bob Mahler, who grows plants for the Preserve’s collections but also for the spring and fall plants sales. These sales, along with the annual Gala, are the two main income sources for the non-profit organisation. Trilliums are the most sought-after plant at the plant sales, Bob tells us, and deservedly so. It takes 5-7yrs from planting the seed before the trilliums are large enough to be sold; no wonder they sell for $12-$15. Bob explains that he collects seeds from one or two species on the Preserve every week. Then he and a team of volunteers pot up the seeds after any necessary stratification and scarification. Bob is moving towards propagating more from cuttings to yield a faster production turnaround.
Part of the mission of BHWP is to promote good landscape stewardship, so BHWP has reached out to the community with its Plant Stewardship Index (PSI) program. Government and private landowners are moving from the realm of land acquisition to land stewardship and this is where BHWP can help, says Jeannine Vannais, PSI Coordinator at BHWP. The PSI can assess the vitality of remnant plant communities. It provides a quantitative approach to land assessment where a coefficient of conservatism (CC; ranging from 0 to 10) is assigned to each plant species by experienced botanists. Plants with a zero are non-native invasive species while those with a value of 10 are the most conservative species. The online PSI website conveniently lets land owners enter the list of plants found in the assessment area. The PSI is then calculated based on the CC of the plants present, which indicates the naturalness of the site and how the land management practises have affected the site.
So what is in the future for the Preserve? The exciting news says, Miles Arnott, Executive Director of BHWP is that Washington Crossing Historic Park is looking to transfer Bowman’s Tower to BHWP, which will add another ecological community and an important migratory bird flyway to the BHWP property. The addition of the Tower fits well with BHWP’s master plan that outlines ideas to attract more visitors through attractions such as a new visitors centre and butterfly enclosure. As we concluded our tour through BHWP, we were surprised to see a cactus (Opuntia humifusa) complete with a solitary yellow flower. Amy assured us that it is indeed native to Pennsylvania. One of many learning experience we enjoyed during our day at the Preserve.