University of Richmond UR Scholarship Repository

Biology Faculty Publications Biology

Spring 2020

Difficult eek,Cr Difficult Management Choices

W. John Hayden University of Richmond, [email protected]

Follow this and additional works at: https://scholarship.richmond.edu/biology-faculty-publications

Part of the Botany Commons

Recommended Citation Hayden, John W. "Difficult eek,Cr Difficult Management Choices." Sempervirens: The Quarterly of the Virginia Native Plant Society (Spring, 2020): 8-9.

This Article is brought to you for free and open access by the Biology at UR Scholarship Repository. It has been accepted for inclusion in Biology Faculty Publications by an authorized administrator of UR Scholarship Repository. For more information, please contact [email protected]. 8 Sempervirens, Spring 2020 Difficult Creek, difficult management choices irginia is blessed with many line right-of-way and on roadsides, Vbotanical wonderlands; see places where periodic mowing kept Chapter 4 of the Flora of Virginia shade-casting woody plants in check. (Weakley et al. 2012) for thumbnail But that was enough to demonstrate sketches describing 50 of these special the site’s potential for conservation places. One such treasure, Difficult of rare plants. Over time, 819 acres Creek Natural Area Preserve, is of land encompassing the power line home to a thriving population of right-of-way and adjoining parcels the 2019 VNPS Wildflower of the was acquired and new management year, americanus (New practices, primarily selective cutting Jersey Tea). Paradoxically, however, of trees and periodic controlled burns, our featured wildflower of last year were instituted to restore the pre- is inextricably linked to a difficult settlement savanna habitat. conservation management decision. How special is the Difficult Creek Difficult Creek Natural Area preserve? Here grow: Tall Barbara’s Preserve is located in Halifax County, Buttons (Marshallia legrandii), known between the Dan and Roanoke Rivers, from one other extant population in New Jersey Tea, a few miles northwest of their now nearby Mecklenburg County (and two (John Hayden) inundated confluence, known as Buggs other, now extirpated, populations); deserving of protection at Difficult Island Lake (Kerr Reservoir). In pre- Carolina Thistle (Cirsium Creek? Mottled settlement days, it is believed that the carolinianum), the only other known Erynnis( martialis) natural plant community in this part Virginia population of which is in present a complicating factor. These of Virginia was open, fire-adapted, Franklin County; and American Ipecac butterflies were discovered at Difficult savanna, consisting of scattered (Gillenia stipulata), a rare outlier from Creek in 2008 by Virginia Natural Shortleaf Pines, Oaks, and Hickories, its range further west—to name just a Heritage zoologist, Anne Chazal. interspersed with a diverse assemblage few noteworthy plant species. The Mottled Duskywing is a type of grasses and other herbaceous The Difficult Creek Natural Area of , and it is completely plants. When Alton Harvill and his Preserve also supports a vigorous dependent on Ceanothus species as wife, Barbara, botanized the area in population of New Jersey Tea its larval food plant. Notably, this the early 1970s, a long tradition of fire (Ceanothus americana) which, though species of Duskywing is in decline suppression had certainly altered to relatively common in Virginia, thrives throughout most of its historic range some degree the original nature of the at this site because of the periodic in eastern North America. vegetation; nevertheless, they were able controlled burns that constitute a core Here is the problem: Controlled to document many rare plant species feature of the current management burns, necessary to maintain from the area. A few years later, circa regime. Fire consumes above-ground healthy populations of New Jersey 1980, a new force of change entered shoots of Ceanothus, but this is a fire- Tea and the other rare plants of the scene: much of this botanical adapted plant; well-established plants Difficult Creek, will inevitably have treasure was converted to Loblolly rebound quickly from resources stored some adverse effect on populations Pine plantation. As the canopy in stout roots. Fire benefits such plants of Mottled . The of Loblollies closed, the original by removing saplings of trees that, if problem is that, as fall approaches, assemblage of herbaceous species that permitted to grow, would shade out second brood Mottled Duskywing thrive in sunny conditions became the sun-loving herbs. In this habitat, caterpillars, having eaten their fill restricted to smaller and smaller burning is good, not just for New Jersey of New Jersey Tea leaves, form patches. In June of 1993, Chris Ludwig Tea, but also for other herbaceous weak cocoons of silk-bound, folded, of the Division of Natural Heritage species of the region, many of which leaves; these cocoons are soon shed first visited the site; he was able to are both rare and fire-adapted. from the plant with the rest of relocate many of the rare plants found But, are controlled burns its leaves and become part of the by the Harvills, but only along a power beneficial forall the biodiversity (Continued next page) Sempervirens, Spring 2020 9

and 4) decline of open grassland and savanna habitats. Of these factors, the fourth may be most critical. Mottled Duskywing, Mottled Duskywings not only Erynnis martialis, on New require New Jersey Tea, but they Jersey Tea (Mike Reese, wisconsinbutterflies.org) require their only food plant to be in or adjacent to open, not densely forested, habitat. This requirement springs from the ’s mating strategy. Male Mottled Duskywings are “hilltoppers;” during the mating season, they seek high points like open hilltops, or perhaps an isolated shrub or tree, from (Continued from page 8) of Duskywings, some of which will which to watch for the approach of leaf litter where the fully-grown disperse into recently burned regions females. Evidently, this innate mating caterpillars overwinter. Pupation and where vigorously regenerated shoots behavior does not work well in forested metamorphosis to adult Mottled rising from the unharmed roots of areas where New Jersey Tea could well Duskywing butterflies occur in the New Jersey Tea will beckon egg-laying be present. Certainly, there are multiple spring. Controlled burns for rare females. The idea is to sacrifice some factors involved, but the Mottled plants, generally scheduled during portion of the Mottled Duskywing Duskywing’s requirement for a rare the dormant season, will inevitably population at the preserve in order open habitat that also supports New incinerate the cocooned caterpillars. to maintain the habitat at large, thus Jersey Tea places a stringent limit on As a matter of fact, fire at just about ensuring the long-term survival of the habitats where it can thrive. any time of year can be a catastrophe the butterflies and their required At Difficult Creek, fire is essential. for this Duskywing; fire during the larval food plant. In the big picture, Fire helps New Jersey Tea to thrive, growing season would remove eggs small controlled burns make sense. and vigorous New Jersey Tea plants and actively growing caterpillars. Nevertheless, it must be difficult feed the Mottled Duskywings, and Fire would also temporarily remove to strike a match knowing that the fire keeps the habitat sufficiently open oviposition sites. The irony is that ensuing fire will destroy some portion so that Mottled Duskywings can Mottled Duskywings need fire for of this rare butterfly’s population. mate efficiently. But the amount of their only food plants, Ceanothus Why, one might ask, are Mottled fire needs to be carefully controlled, americanus, to thrive, but those same Duskywings rare when their host food lest this one essential environmental fires inevitably reduce the population plant, New Jersey Tea, is relatively factor, now in the hands of human of this already rare butterfly. common? Four factors have been land managers, inadvertently wipes What is the responsible land implicated in the decline of Mottled out these rare and declining Skippers. manager to do? The management Duskywings: 1) competition for (Johnny Townsend and Chris Ludwig question becomes, not whether to Ceanothus foliage by voracious deer; 2) provided information useful in burn or not burn, but how best to fire, which at any season, will exact a preparation of this article.)v manage fire in this critical habitat. The toll on population size; 3) lethal sprays —John Hayden, Botany Chair solution is to treat the Difficult Creek intended to control Gypsy Moths; preserve as a series of patches, each to be burned in different years. The Tallamy discusses new book, Nature’s Best Hope idea is that, yes, some rare Mottled The Prince William Wildflower Society recently hosted a talk by Dr. Duskywing pupae will go up in Doug Tallamy, author of Bringing Nature Home, published in 2007, and smoke with every fire, but if only a now Nature’s Best Hope: A New Approach to Conservation that Starts in portion of the reserve is burned, only Your Yard. With a capacity crowd that left many people unable to attend, a portion of the butterfly population B.J. Lecrone of Loudoun Wildlife Conservancy volunteered to livestream will be eliminated in any given year. the February 23 event on YouTube. The recording is now available online Every year, unburned portions of the at https://youtu.be/EuNyc4Itni0. See our blog for Sue Dingwell’s review of reserve will produce new generations the book as well. Remember, WE are nature’s best hope.