Final Report for 2012 Edna Bailey Sussman Internship Grant
Assessing the Habitat Characteristics of the Fragrant Cliff Fern (D. fragrans L. Schott) in
Regards to Climate Change and Recreational Land Use
Jessica R. Bouchard
SUNY College of Environmental Science and Forestry
Summary of Proposed Work:
Dryopteris fragrans (L.) Schott (fragrant fern) is a globally secure but rare fern in the Northern
Forests region of the eastern United States. It has a circumpolar distribution in the northern
hemisphere, with the southernmost distribution reaching the temperate Northern Forests, a 10.52
million hectare land area that stretches from eastern Maine through New Hampshire and Vermont and
into northern New York. D. fragrans has State Heritage Program Ranks of S1 in NY, representing
between 1-5 occurrences, S2 in both VT and NH, representing between 6-20 occurrences in each state,
and S3 in ME, representing 21-35 occurrences. Reduced habitat suitability near D. fragrans range
margin may be responsible for its sparse distribution and small population sizes. Atypical of wood
ferns, it occurs in crevices on cliff faces within the Northern Forests, and is most threatened not only by
climate warming but also recreational land use.
The purpose of this internship was to assist Dr. Scott Bailey, my co-adviser and a soil scientist
with the USDA Forest Service, in establishing the habitat characteristics of 16 D. fragrans populations
throughout the Northern Forests of NY, VT, NH, and ME. The objectives of this research were to: 1)
measure and record vegetative factors at each site; 2) measure and record edaphic factors at each site;
and 3) compile and submit data to Dr. Bailey for analysis of habitat characteristics. The goal of this
internship is to provide baseline information on the habitat requirements of D. fragrans in the Northern
Forests. Data obtained from this internship experience will reveal populations most threatened by
extirpation and inform decision makers on the most appropriate long-term management plan. Habitat
characteristics will eventually be correlated with my thesis research, which involves investigating the
genetic and phenotypic diversity of peripheral D. fragrans populations in the Northern Forests, as a
comprehensive approach to assess how this species is responding to a warmer climate and its potential
to withstand future climate change.
Work Completed:
During the summer of 2012 I visited 16 D. fragrans populations to record vegetative and
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edaphic habitat characteristics, to collect water samples from cliff seeps, and to install temperature
logging Ibuttons. The sixteen population sites (n=16) were divided among four states, NY, VT, NH,
and ME, with four sites per state. Cliff face plots for habitat analysis measured 250m², and were
centered around the largest accessible group of D. fragrans at each site. Vegetative measurements
included an estimated count of D. fragrans individuals, identification of vascular plants, estimation of
percent cover by vegetation, and estimation of percent cover by bryophytes. Measured edaphic habitat
characteristics included Universal Transverse Mercator (UTM), elevation, aspect, cliff height, cliff
shape (overall angle and shape as well as micro-habitat structures such as overhangs, benches, etc. in
the immediate vicinity of D. fragrans), joint description, spacing and orientation of joints, talus type,
angles of open sky, percent sky shaded by vegetation, and the vegetative community above and below
the cliff. Three IButtons (Embedded Data Systems) were installed per site, on the trunks of trees at
approximately eye level, and were set to record air temperature every 65 minutes for one year to
characterize the climate at each cliff. All attempts were made to space IButtons equal distances from
each other on trees that were nearest the cliff face plots. Where present, water seeps were obtained
either by syringing moss or by collecting drips directly from seeps. Lithology and rock samples were
collected by Bailey, and he will determine mineralogy by optical petrography. Water seep samples will
be tested by Bailey for concentration of major ions and pH. Data for each site was entered into an
Excel spreadsheet and sent to Bailey. Throughout the field season my work was supervised by Dr.
Bailey via meetings, phone conversations, and emails. All necessary permits were obtained to access
the cliffs that D. fragrans inhabits in the Northern Forests.
Preliminary Results:
Although full analysis of habitat characteristics will be completed by Scott Bailey, I have
compiled preliminary descriptive statistics on some of the vegetative factors recorded in the 250m² plot
at each site. The percent vascular plant cover on each plot ranged between 0.5% to 35%, with NH-RM
(Rattlesnake Mountain, NH) having the lowest cover by vascular plants and NH-IG (Ice Gulch, NH)
having the greatest (Fig. 1). All but two plots had less than 10% vascular plant cover, indicating
predominantly sparse vegetation and what appears to be low productivity on the cliff face plots. This
observation may provide insight on the level of competition that is occurring in these cliff plant
communities.
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Percent Vascular Plant Cover at Each Site
% Cover by Vascular Plants
40%
NY-AZ
NY-HP
NY-WR
NY-HR
VT-DM
VT-OH
VT-MM
VT-ME
35%
30%
25%
20%
15%
10%
5%
NH-IG
NH-RM
NH-MM
NH-CH
ME-AC
ME-RG
ME-KM
ME-SM
0%
Sites
Figure 1. Percent vascular plant cover on the 250m² plot at each site.
Percent cover by bryophytes ranged from 0.5% to 45%, and VT-OH (Owl's Head, VT), ME-KM
(Mt. Kineo, ME), ME-SM (Soubunge Mountain, ME), and NH-RM (Rattlesnake Mountain, NH) all
had the lowest percent cover and NH-IG (Ice Gulch, NH) had the highest. The majority of plots (n=13)
were sparsely covered by bryophytes and exhibited <5% cover. Bryophytes were most often
associated with fractures on the cliff face and features such as shelves, overhangs, caves, and ceilings.
% Cover by Bryophytes
Percent Bryophyte Cover at Each Site
50.00%
45.00%
40.00%
35.00%
30.00%
25.00%
20.00%
15.00%
10.00%
5.00%
0.00%
NY-AZ
NY-HP
NY-WR
NY-HR
VT-DM
VT-OH
VT-MM
VT-ME
NH-IG
NH-RM
NH-MM
NH-CH
ME-AC
ME-RG
ME-KM
ME-SM
Sites
Figure 2. Percent bryophyte cover on the 250m² plot at each site.
An estimated inventory of D. fragrans was conducted within each plot and along the entirety of
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most cliff faces where the plots were located, with the exception of a few very long cliffs. Because
multiple tiers of cliffs occurred at numerous sites, there may have been additional individuals that were
not counted on neighboring cliffs. Therefore it is important to emphasize that this inventory is only an
estimate, as counts were performed only on the cliffs where plots were positioned. The number of
individuals found on each cliff ranged from 10 to >150.
Table 1. Estimated number of D. fragrans individuals at each site.
Location
NY-AZ
NY-HP
NY-WR
NY-HR
VT-DM
VT-OH
VT-MM
VT-ME
NH-IG
NH-RM
NH-MM
NH-CH
ME-AC
ME-RG
ME-KM
ME-SM
Estimated no. of Df individuals
10
11
>85
30
>150
42
14
91
28
89
61
86
10
>150
>15
140
Future Work:
Future work will include revisiting the 16 sites next summer to collect and extract data from
Ibuttons. The diurnal temperature fluctuations and monthly and seasonal temperature means, minima,
and maxima will be statistically compared across all sites. Following analysis of habitat characteristics,
results will be correlated to the genetic and phenotypic diversity study to understand population
dynamics and identify the most appropriate management plan.
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Cliff face at Deer Mountain, VT with numerous D. fragrans individuals
Close up of D. fragrans at Deer Mountain, VT
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