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Research Questions

The following research questions address plant taxa that are globally or regionally rare. The New England Wild Flower Society has recently published comprehensive Conservation and Research Plans that review the conservation status of each taxon and that suggest specific actions to ensure their conservation within their New England range over the next twenty years.

Abridged versions of these Conservation and Research Plans are available for download at our web site by clicking on the taxa below, and provide an excellent general introduction to the ecology of the taxon and the known causes of its rarity. Most of these Plans pinpoint areas where we lack basic knowledge on the biology of the plant -- knowledge that is critical to understanding how best to conserve and protect it. Thus, the New England Wild Flower Society seeks to fund basic research studies that will elucidate the factors that influence plant fitness, interactions among populations, and population trends. These studies may yield some of the first data available on these plants, and will assist with conservation planning for these and many other rare plants. The questions that follow derive directly from the Conservation and Research Plans themselves.

In Summer 2002, NSF/NEWFS Fellows studied a diverse range of species and topics, including the pollination biology of Corydalis flavula in Michigan, population genetics and seed dispersal of Liatris borealis in Rhode Island, and impacts of herbivory on reproductive output of Trollius laxus, comparing rare and common subspecies in Connecticut and Colorado.

As you design a research study to address these questions, we recommend you take the following steps:

1. Perform background research on the taxon.

• Read the Conservation and Research Plan relating to the plant(s)  http://www.newfs.org/conplans.html 
• Search for other sources of information on the species (see "Tips for Searching for Information on Plants”) http://www.newfs.org/researchtips.htm
• Use your own knowledge of other plants to form hypotheses. Bounce your ideas off your academic advisor or other knowledgeable biologists. 

2. Design an experiment or set of experiments to address the hypotheses you have generated. Keep in mind the following:

• Non-destructive field experiments should be performed. We do not wish to endanger plant populations in the process of studying them. Experimental design will be contingent on permitting by the relevant Natural Heritage Programs and on obtaining landowner permission. Thus, you should develop your design to be as non-invasive as possible and to minimize logistical difficulties, and if you are awarded a fellowship, you should be prepared to work flexibly in developing your final design.
• Simple, inexpensive techniques can be extremely effective for obtaining good information.
• Remember to build adequate replication and statistical power into your design (or review statistical techniques that will permit analyses of small data sets).

Species and Research Topics

1. Adiantum viridimontanum

Investigate ecological distributions and interactions among members
of the Adiantum pedatum complex. Several aspects of Green Mountain
maidenhair fern’s biology are poorly understood. In particular, further
research is recommended to examine how members of the Adiantum
pedatum complex are distributed across ecological gradients and how
members of the complex interact in locations where they co-occur.
Increased knowledge of the hybridization frequency between Adiantum
viridimontanum and its progenitors would be useful, as would information
about the factors that influence the formation, distribution on the landscape,
and success of species and hybrids. Field investigations of these questions
would be aided by a better description of field characters that can be used to
distinguish A. viridimontanum from its hybrids.
Research spore banking. Information about spore viability under various
storage regimes is currently lacking, so the success of spore banking as a
conservation action will depend on further research in this area.

2. Agastache nepetoides

Genetic testing to determine the relationship of disjunct Connecticut
and Vermont populations with each other and with other populations in the
nearby range of New England occurrences
Perform field experiments to determine annual rates of survival and
reproduction for A. nepetoides at Norcross and NEWFS Garden in the
Woods for their current populations and also for the extant Vermont and
Connecticut populations. It would also be interesting to compare populations
in which the habitat is maintained to provide open conditions with habitat that
is left to ecological succession.

3. Agastache scrophulariifolia

It is not known whether seeds are persistent and viable in the soil
seed bank. A study to determine seed viablility in the soil should be
conducted at stations where plants have not been observed recently.
Experiments should be conducted at VT. 001 (Pownal), MA No EO
Number (West Cummington) and at CT .001 (Roxbury). Competing growth
should be removed to allow sunlight penetration followed by soil scarification
as described in the conservation and research plan.

4. Amerorchis rotundifolia

Are current adult plants surviving? If not, try to identify what might have
changed in the habitat to decrease survival. Are new plants establishing in
sufficient numbers to balance adult mortality? If clonal, what is the balance
between clonal and sexual reproduction? What habitat changes are
decreasing vegetative reproduction? Are seedlings or small plants present? If
not, are seeds being produced? If so, is dispersal of seeds to unsuitable
habitat high? Is seed predation high or seed survival in soil low? Do seeds
germinate? Is survival of small seedlings low? If no seeds, are pollinators
visiting the flowers? If they are, is pollen being transferred? Are individuals
self-sterile? Is fruit abortion high? If there is no pollination, why not?
Gather more information regarding pollination and potential insect
herbivory. An insect survey should be conducted at Amerorchis flowering
time. Insect specimens should be collected for identification purposes, and
field observations should be conducted to observe what is visiting the
flowers

Determine microsite preferences of the plant. The general habitat of
Amerorchis is understood to be northern white-cedar swamp, but microsite
information is lacking. Is there a feature of microsite that enhances
germination, presence, or survival? Other aspects that should be examined
include temperature, light, mycorrhizal relations, and competition with other
plants for resources.
Mycorrhizal relationships need to be explored, and if possible, those
necessary for germination should be determined. Rasmussen and Whigham
(1993) present a method to study germination and development of orchid
seedlings in the field, and they present suggestions for improvement on their
method.

5. Aristolochia serpentaria

Characterize in detail the preferred microhabitats of this plant.
Study plant-insect interactions including herbivory, use of plants as
oviposition sites by butterflies, and pollination dynamics.

6. Asclepias purpurascens

Note: New England populations of this plant are currently too small and precarious
to permit manipulative studies or intensive field research. However, larger
populations elsewhere in the plants' range could be studied to provide information.
Among the questions that require answers are:

What factors limit fruit set in A. purpurascens?
What environmental factors limit establishment and growth of A.
purpurascens? Determine soil pH, calcium/magnesium content, and
moisture capacity at sites where the species occurs. Light availability should
be characterized by recording photosynthetically-active radiation (PAR)
above plants, preferably using time-integrated measures (e.g., Pearcy et al.
1997).
Examine levels of competition with co-occurring plant species,
possibly through thinning experiments.
Document land-use history and indices of disturbance of these sites.
Characterize levels of genetic variability in small and large populations
outside New England and determine levels of outcrossing and
inter-population exchange

7. Aster concolor

Determine habitat preferences. Comparisons with habitat preferences of
prolific southern populations could be especially helpful. Create a model for
optimum habitat on Nantucket and in New England to provide a habitat
management target.
Investigate reproductive biology. Determine whether the species is
self-compatible; determine levels of reproduction in the wild; investigate its
response to fire.
Determine metapopulation status. Investigate and map the spatial
configuration of all EOs; determine dispersal distances and potential for
migration to existing EOs or colonization of new habitats; determine length of
persistence of occurrences (sub-populations) with and without disturbance;
determine the longevity of the seed-bank.
Develop an understanding of A. concolor’s pollinators, especially their
habitat requirements and range of travel in order to help determine
connectivity of sub-populations.
Investigate the role of insect herbivory and seed predation.
Specifically, investigate the role of herbivory by rabbits, particularly the
impact of the introduced Eastern Cottontail on Nantucket, to determine if
reintroduction would be more successful in areas inhabited only by the native
New England cottontail.

8. Carex atherodes

Quantify areal extent, number of stems, and number of sexually
reproductive culms for each population.
Quantify seed production and limits to reproduction at as many
populations as possible.
Determine possible threats of invasive exotic plants at several sites.

9. Carex barrattii

Investigate the habitat conditions that promote germination and
establishment of C. barrattii, inside and outside its New England range.
How these conditions might be promoted in natural populations? Many
biologists who were contacted mentioned the probability that fire plays an
important role in the reproductive success of the species. Study plots should
be established so that controlled burning could be contrasted with canopy
clearing and the end results closely monitored. Reproductive success could
then be measured for the different treatments.
Investigate the taxon’s response to changing water levels.

10. Carex garberi

Study riverside seep habitats. Little is known either about the biology of
this species or the ecology of riverside seeps. Studies contributing to the
understanding of the ecology of this taxon are needed to understand the
mechanisms responsible for establishment, maintenance, and dispersal of C.
garberi occurrences as well as other species in the riverside seep
community.
Why is Carex garberi not found in all areas along the river shores?
Is flooding or ice scour more important to survival of the plants?
What is the minimum viable population size?
Studies to quantify the genetic isolation of the Connecticut and Maine
river populations would help guide conservation planning.

11. Carex polymorpha

Study germination dynamics in the field and greenhouse. Previous
investigators (e.g., Standley 1989) report little success in germinating seeds
of Carex polymorpha.

12. Carex richardsonii

Determine the predominant mode of reproduction in the field. Is most
of the reproduction clonal or by sexual reproduction? The nature of
reproduction has long-term consequences for its survival. One would expect
that genetic diversity would decrease in small, isolated populations that are
reproducing clonally over long periods of time. However, data from Jonsson
and others (1996) and McClintock and Waterway (1993) suggest that
relatively high levels of genetic variation do exist in clonal sedges. In a few
species of Carex, genetic variation is similar to many wind-pollinated and
out-crossing species. Hence, genetic diversity may still be high at these
subpopulations if they are reproducing sexually. Also, monitor seeding
recruitment.

13. Carex wiegandii

Reproductive biology: Gaining a better understanding of Carex
wiegandii’s sexual reproduction is fundamental to informing management
and protection decisions. A primary conservation action for this sedge
recommends that two populations in the White Mountain National Forest
(NH .007 [Lincoln] and NH .008 [Livermore]), two populations in Acadia
National Park (ME .019 [Bar Harbor] and ME .020 [Mount Desert]), and
the one site in Conte Refuge (VT .006 [Lewis]) should be studied to
determine the sedge’s phenology, pollen viability, seed production, soil seed
banking, dispersal mechanisms, and germination requirements.
The proportion of populations occurring in dynamic habitats should be
more thoroughly researched and used as a yardstick in understanding trends
in the regional status of Carex wiegandii and to inform conservation and
management action (A. A. Reznicek, personal communication with W.
Nichols, 2001).
Effects of timbering: Research should also address the compatibility of the
sedge’s continued presence with successional processes in timber harvested
areas.

14. Castilleja coccinea

Soil studies and species inventories of the extant sites should be
carried out to determine whether any broad generalizations can be made
about the range of soil factors that support the species.
Determine the extent to which shading (and removal of shade)
influences growth, survivorship, or recruitment of the species.

The plant is a hemiparasite, but its host requirements are unknown.
Identifying associated species might be important in developing a profile of
appropriate habitat. William Moorhead (personal communication) has
observed at the extant sites a suite of associated species that tend to be
associated with alkaline soils. He feels that the species may be associated
with seeps in soils deriving from limestone bedrock or calcareous tills. Leslie
Mehrhoff (personal communication) considers associated species such as
Gentianopsis crinata and Parnassia glauca to be more generally
indicative of rich sites. Likewise, Linke (1980) and Smith (1983)
independently report this species associated with Indian paintbrush at
different sites. The work done on C. coccinea by Malcolm (1962a, 1962b)
and evidence from other species of the same genus (Heckard 1962, Mills
and Kummerow 1988) indicates the genus is a rather generalist parasite.
However, Marvier (1998) found that host quality varies and a "mixed diet"
promotes the highest reproductive success while diminishing the growth of
herbivores on C. wightii. Marvier and Smith (1997) discuss the potential
importance of recognizing and preserving the appropriate host assemblage to
the conservation of parasitic plant species. Using a list of the associated
species at CT. 004, common garden experiments should be undertaken to
determine whether some hosts support greater reproductive success in C.
coccinea. Host-parasite relationships may also influence germination
success.
Characterize the effects of disturbance on the species: churning of
wetland soils by some type of grazing mammals was an historically important
component of the Indian paintbrush ecology. Each of the two most viable
extant sites has experienced some soil disturbance annually for several years:
one is mowed for hay and the other was grazed until recently. Disturbance
should be explored in the field to determine how it might affect the success of
germination and recruitment.
In variably sized experimental plots, Allee effects should be explored
by comparing seed set between "populations" as a consequence of
different plant densities. Evidence seems to indicate that pollinator
availability is not limiting seed production at this site. However, Allee effects
might be important in the smaller extant populations.

15. Corydalis flavula

Determine whether removal of encroaching shrubs at one Connecticut
site enhances survivorship, growth, and recruitment of the plants.
Determine primary pollinators of the species in Connecticut (these may
include a rare butterfly) and assess the relative contributions of insect
pollination and self-pollination (cleistogamy) to reproductive success
With four moderately secure populations in Connecticut, most of which may
rely heavily on cleistogamous reproduction to set seed, it is of interest to
determine: 1) the genetic relatedness among these populations and the
nearest populations outside New England and 2) levels of genetic
variability within populations and the ramifications of this for seed set and
seedling establishment.

16. Cynoglossum virginianum var. boreale

Research pollinator ecology and possible pollinator limitation: An
experiment comparing flowers that are hand-crossed, self-pollinated by
hand, and bagged to exclude pollinators should be performed to quantify
pollinator limitation and out-crossing effects on seed set at either the sites in
Maine or New Hampshire. In populations where pollinator visitation is
believed to limit seed production, flowers should be hand-pollinated to
decrease pollinator limitation due to small population size. An additional
benefit is that deleterious genetic effects may be reduced by hand-crossing
pollen.

17. Desmodium cuspidatum

Determine degree of self-incompatibility. This could be accomplished
through bagging experiments, either in the wild or on garden plants. Using
garden plants will be preferable, given the small number of current
populations in New England.
Describe pollination mechanism, particularly whether a "tripping"
mechanism is an essential part of pollination in wild populations.
Identify pollinator species. This is best accomplished by observations of
wild populations. At the same time, observations of any nectar robbing and
concomitant bypassing of pollination would be useful.

Quantify percentage of viable seed set in the wild. Seed collected for
establishment of cultivated colonies (which may then be used for further
research or for production of plants or seed for re-introductions) can be
tested for germination percentages. It would be useful to know this
percentage for the large populations in Massachusetts (MA 1 [North
Adams] and MA 6 [Holyoke]), as well as for large populations in
Connecticut and Rhode Island, if any can be located. The percentage of
seed set in these apparently flourishing populations can then be compared to
seed set in very small populations, such as VT .001 (West Rutland).
Study seed dispersal. Nothing seems to be known about dispersal of
Desmodium seeds in general, although adaptation to long-distance dispersal
via mammalian or bird vectors is generally assumed from the seed
morphology, i.e., their "sticky" outer coats. Although likely to be difficult,
studies of dispersal distances in the wild, perhaps for more common
co-occurring congeners, would be helpful.
Define genets versus ramets. It is unclear how far a genet spreads in the
wild, if at all. This should be determined, if only to clarify the basic
population structure.
Determine genetic structure of populations. Studies of extant
populations through New England, possibly in comparison to more common
congeners in New England and to D. cuspidatum populations in the center
of its range, may clarify any genetic bottlenecks affecting the species in New
England.
Quantify population size variation. One current New England population
(MA #1) was determined to have nine plants in 1998 and 60 plants in 2001.
Assuming this was not due to differences in survey effort, this demonstrates
an ability for rapid population growth. Garden plants, possibly at the Garden
in the Woods of the NEWFS, should be observed to see how long it takes
for a seedling to reach reproductive size and for a minimal population size to
grow via local reseeding. Several wild populations should be observed
annually for five to ten years each, to determine fluctuations in population
size.
Describe rhizobial interactions. New England Desmodium cuspidatum
should be checked for the presence of rhizobial nodules. It would be useful
to know the extent of "sharing" of rhizobial species across co-occurring
legumes and other plants in each current occurrence. Inoculation of garden
or greenhouse colonies of D. cuspidatum with rhizobia from flourishing wild
colonies may show whether the presence/absence of specific rhizobial strains
is necessary for vigorous growth of D. cuspidatum.
Identify insect pests or susceptibility to deer browsing. Natural
Heritage field forms indicate that some populations experience noticeable
insect damage. The species of insect responsible, along with the extent of
damage, should be observed for wild populations. While deer damage was
not noted on field forms, similar observations of the extent of damage due to
deer would be useful.

18. Diphasiastrum sitchense

Special studies on clonal size, productivity and fertility are encouraged
to determine growth rate, extent and possible extent of clones, and to
determine optimum sustainable populations. No guidelines as to the definition
or measurement of this optimum can be given at present; they should be
developed by anyone undertaking such research.

19. Eriocaulon parkeri

Determine phenology, pollination mechanisms and vectors, pollen
viability, seed production, seed dispersal, and seed germination.
Determining method of pollination may be difficult, as standard techniques
such as emasculation and pollen exclusion bags will not work for this aquatic
species without modification. Pollen viability, seed production, and seed
germination studies might be expanded to explore differences in location and
water quality (urban versus rural sites) in an effort to understand the declines
of this species from populated areas.

20. Eupatorium leucolepis var. novae-angliae

Initiate studies on the taxon’s population biology, including
reproductive methods, germination requirements, seed dispersal, and
dormancy. The taxon employs unusual reproduction. Flowers lack pollen
and therefore are "male-sterile" (Sullivan 1992). The plant reproduces by
two asexual processes. Clonal growth is the more observable of these
processes, and the dense masses of plants found on the upper shorelines of
many ponds result from vegetative extensions of stolons and stems. The
plant’s other reproductive method is the production of viable seeds and
embryo without sexual reproduction, a process known as agamospermy.
How is genetic variability maintained in populations?
Determine taxonomic status of the taxon. Sullivan (1992) suggested
that, contrary to Fernald’s taxonomic determination based on morphology,
New England boneset is a self-sustaining hybrid between Eupatorium
resinosum and Eupatorium album. She concluded that E. l.
novae-angliae is not closely related to E. l. leucolepis, and proposed that
New England boneset receive full species status. Wiefenbach’s (1993)
follow-up genetic tests ruled out Eupatorium album as a parent species,
but supported Sullivan’s hypothesis that Eupatorium leucolepis var.
novae-angliae is a naturally reproducing polyploid taxon of hybrid origin.
Her tests indicated that Eupatorium resinosum is a probable parent of
Eupatorium leucolepis var. novae-angliae but that other antecedents are
unknown. Wiefenbach (1993: 19) concluded that New England boneset is a
paleohybrid of uncertain parentage, which originated after the most recent
glaciation (10,000 years ago), and that it is "the product of a unique event
from a distant time that cannot be repeated." The genetic relationship of
Eupatorium leucolepis var. novae-angliae to Eupatorium leucolepis var.
leucolepis requires further clarification. Conduct DNA tests that will clarify
and potentially redefine the taxonomic relationships of Eupatorium
leucolepis var. novae-angliae with Eupatorium leucolepis var. leucolepis
and other members of the genus Eupatorium.

21. Hackelia deflexa var. americana

Study ecological interactions to determine how pollination, seed
dispersal, and herbivory affect plant population structure. Quantify the
species that visit northern stickseed flowers, and the resources (e.g., nectar
and pollen) they take from them. Determine the frequency with which
northern stickseed self-pollinates. Identify species that disperse the seeds,
and describe their movement patterns. Assess the degree of genetic isolation
between populations, and study the genetic diversity of these small
populations. Examine the effect of herbivory on plant reproductive success.
In studying all of these interactions, determine whether northern stickseed
has specialized ecological relationships with any other organisms, the loss of
which might jeopardize populations of the plant.
Assess the species’ response to various forms of natural and
anthropogenic disturbance. Examine the kinds of substrate on which
seeds germinate, and try to correlate these with disturbance processes (such
as erosion of outcrops). Study whether northern stickseed favors disturbed
sites because ecological competition from other vegetation is low (as
suggested by Gentry and Carr 1976), or for some other reason. Determine
whether human forms of disturbance, such as logging and trail use, mimic
natural disturbance factors to create habitat, or destroy habitat through
different processes. Trail use could be studied at VT .005 (Salisbury) and
VT .009 (Shelburne). Effects of logging might be investigated at ME .003
(West Paris), VT .010 (Shelburne), and VT .011 (Milton). Given the small
number of individuals in each population and the fact that the plant is rare,
manipulative studies of recreational and extractive use of northern stickseed
habitat would be inappropriate. Instead, workers should focus on gathering
of observational data about trails and logging.

22. Hasteola suaveolens

It would be useful to know why the plant seems to flourish in cultivation, yet is
declining in its natural habitat throughout most of its range. The following questions
are suggested as appropriate topics of research for H. suaveolens:

What is the relative importance of sexual reproduction versus
vegetative propagation to the persistence of populations?
Is H. suaveolens self-incompatible and is the number of compatibility
groups in our populations small enough to limit seed production?
Is a lack of suitable pollinators responsible for low seed set in our
populations?
What are the conditions that promote germination and establishment
of H. suaveolens? How might these conditions be promoted in natural
populations?
Which life history stages are most important to limiting population
growth of H. suaveolens?

What are the consistent ecological differences between the site
where the New England population occurs and the sites of large,
healthy populations in other states that could account for the difference
in population size?

23. Hydrophyllum canadense

Develop a consistent, efficient, and minimum-impact monitoring
technique to accurately assess population sizes and trends over time while
minimizing potential negative impacts such as trampling plants and damaging
the habitat during sampling. It will be informative to use some combination of
counting plants and mapping the locations of concentrations of the plants. It
will be important to determine the most practical and accurate way to count
plants. Currently, stems, clumps, and plants have been used to describe the
plants; this likely results in counts that are not comparable. Ideally, a
standardized sampling regime should be established for all of the populations
using one measure.
Determine optimal light, moisture, and nutrient levels for the species.
Determine the relative importance of sexual and asexual
reproduction.
Determine the impacts of exotic invasive plant species and means of
controlling them.
Determine the role of disturbance (e.g., flooding and ice scouring) in the
population ecology of the plant; determining the nature of herbivory seen in
populations.
Determine the impacts of various current land uses and investigate
land use history and its impact on populations.

24. Hypericum adpressum

Determine the ecological significance of the two growth forms. Some
populations of Hypericum adpressum are characterized by robust plants
with spongy stems and thickened bases, called forma spongiosum. In
general, typical H. adpressum appears like an annual plant, with population
numbers fluctuating from year to year based on the depth of water and
consequent degree of pond shore exposure at particular sites. In contrast,
the spongiose form of H. adpressum occurs as one component of relatively
persistent emergent plant communities that develop in the littoral zone of
ponds that do not undergo significant annual water level fluctuations. In the
first situation (typical H. adpressum), populations are dependent on
unpredictable and highly fluctuating water levels that result in ephemeral
shoreline exposure. In the second case (form spongiosum), populations
persist and remain relatively unchanged over the course of many years. Thus,
conservation strategies must be adapted to the particular ecology of the
subject habitat. One particular biological question regarding the conservation
of H. adpressum concerns the taxonomic and ecological significance of the
two forms of this species: typical adpressum and the form spongiosum.
Although it is assumed that the morphological differences between these two
forms are due to environmental factors (stability of water level and degree of
immersion), it is possible that genetic variation may also be indicated.

25. Liatris borealis

Further investigate the role of seed predators. Clarify the relationship of
L. borealis and seed predating microlepidopteran moth species. Continue
work of Dr. David Wagner (University of Connecticut) on rearing out larva
collected from L. borealis seed heads. Of particular ecological importance
and interest is the previously unknown tortricid species that may be an
obligate feeder of L. borealis. If this is the case, the fate of this insect
species will depend on the fate of its host plant.
Investigate geologic habitat preferences. Take soil samples from sites
throughout the range and analyze to make generalizations about required soil
types. The existence of soil preferences could also be examined by using soil
maps. Populations can be located, via Global Positioning Systems (GPS) or
traditional techniques, on geologic maps. These maps can be used to search
for soil and other geological patterns in habitat preference. A GIS data base,
which is updated with information from monitoring every 1 to 5 years, would
be beneficial to conservation of this plant for many reasons. Such a database
would enable assessment of trends by area in extirpation, habitat type,
geologic preferences, and other important characteristics.
Test for presence and longevity of a seed bank.
Determine reproductive age and life expectancy. Basic life history
characteristics are not known about L. borealis, and this information is
valuable in assessing the health of a population. Individual plants should be
tagged and followed throughout their life cycle to determine reproductive age
and life expectancy of this species. These data can be obtained as part of the
demographic studies recommended above.

26. Listera auriculata

Identify possible habitat; to discover dispersal mechanisms (e.g.,
tolerance of seeds for water dispersal and effectiveness of wind as a
dispersal agent for short-statured plants); to determine how big an area can
support a metapopulation (so we can comfortably decide to protect a certain
size of preserve); and to develop a template to guide searches for new
populations.

27. Listera convallarioides

Characterize L. convallarioides preferred habitat. Studying populations
in states where the orchid is not rare (e.g., Vermont, Maine) might help
answer these questions: What type of habitat is most likely to harbor
populations? How does slope, with its effect on water velocity and hence
substrate and water depth, affect populations? What range of water pH,
alkalinity, and temperature does L. convallarioides enjoy? How is it
dispersed between patches of habitat? Does it need perennial water or can it
tolerate dry periods? Hall et al. (2001) found that environmental influences
that correlated with plant species in a seep are pH, concentration of major
ions, percentage of open water, and substrate height above the water table.
Although growing conditions for northern white cedar are fairly well defined
(Johnston 1990, Sperduto and Engstrom 1998, Thompson and Sorenson
2000), the microhabitat for L. convallarioides could use clarification.
Study pollination. It would also be useful to discover whether L.
convallarioides has a variety of pollinators, to rule out dependence on a
single, perhaps vulnerable, insect. More knowledge about the fungus that
sometimes attacks L. convallarioides might let us know whether it affects
long-term survival of a population.

28. Listera cordata

We need to characterize the microhabitat preferences of the plant in
the New England sites where it occurs. Although the plant grows in dry
duff in the west, in the northeast the species appears to prefer habitat that is
at least seasonally moist. It would be of interest to gather information on
moisture regime (perennial or seasonal), pH of water and soil, and light
availability for populations where it is relatively common, for example Maine
and Wisconsin, in addition to New Hampshire.

29. Ludwigia polycarpa

Study the hydrological requirements of the species and its habitat.
Study the relationship between light levels and occurrence and vigor
of individuals and populations.
Study life history components and determine potentially vulnerable stages
in the life cycle.

30. Ludwigia sphaerocarpa

In light of growing demands for water withdrawal within its coastal plain
habitat, the most critical information needed in terms of long term
management is L. sphaerocarpa's response to water level changes,
both natural and artificial. By investigating historic water level fluctuations
for existing stations, it may be possible to determine the range of tolerance
for water level variation. Any field investigations along this line should also
note the relationship of other rare plant species to water level
fluctuations/manipulations.
Additional information on population demographics is also desirable.
Data confirming the growth patterns and vigor of populations in sheltered
versus exposed micro-habitats would contribute to the tailoring of future
conservation actions.

31. Mimulus moschatus

Survey for historic occurrences. In addition to the above extant
occurrences, there are two historic naturally occurring populations in
Deerfield and Orange, Massachusetts. Efforts to find these occurrences
should be pursued. Locating these occurrences would be important in
extending the geographical distribution of the species. There are also reports
of undocumented populations in northern Vermont, which should be
researched and surveyed.
Collect basic demographic data on existing populations.
Perform a morphological analysis (possibly complementing a genetic
analysis pending other, larger funding sources) of the affinity and relatedness
of New England and western populations of Mimulus moschatus.

32. Nabalus serpentarius

Study seed dispersal, viability, and germination. The distance over
which seeds are dispersed is unknown. Poor germination has been observed
at the New England Wild Flower Society. Either the seeds are not viable
due, perhaps, to self-incompatibility, or the correct germination conditions
are not known. If populations are to be increased in size, a large supply of
plants would be required, so ability to germinate and raise the seedlings will
be an essential first step.
Determine dynamics of soil seed bank and survival of seedlings. If
this species is monocarpic, the persistence of these populations will depend
on the presence of sufficient seeds in the soil. The lifetime of the seeds in the
soil seed bank, the percent germination of the seeds, and the percent survival
of seedlings will provide information on the viability of the populations and
the need for augmentation or introduction.
Study potential self-incompatibility. Many Asteraceae tested to date
have sporophytic self-incompatibility. No information exists on the genus
Nabalus. If the species is self-incompatible, populations must exceed a
critical size to maintain sufficient S alleles to permit successful reproduction
(Byers and Meagher 1992). Some small populations of Asteraceae have
evolved self-compatibility in response to strong selection at reduced
population size. Experiments should compare seed set in self-pollinated and
cross-pollinated individuals. Individuals from various New England
populations should be crossed to determine S allele diversity if
self-incompatibility is found. For example, see the experiments performed by
Reinartz and Les (1994) and Byers (1995).
Characterize growth habit. Although Nabalus serpentarius is generally
considered a perennial, observations indicate that the species is monocarpic
and dies after flowering. Confirmation of these observations is needed, and
can be obtained by closer observation of existing populations over several
years. Small populations of plants that are short-lived and do not reproduce
vegetatively are at greater risk of extinction than perennials or colonial plants
(Fischer and Stocklin 1997) and have larger minimal viable population
requirements than perennials and species with vegetative reproduction
(Pavlik 1996).
Quantify demography. It is not known whether the existing populations are
growing or declining. Such information is required for a population viability
analysis.
Describe the role of fire in relation to the plant. The largest population
of Nabalus serpentarius in New England grows in a habitat, sandplain
heathland, adapted to fire (Barbour et al. 1998). Burning might simply
provide open habitat for this species, but fire could play a role in the biology
of the species, perhaps by promoting seed germination, and ex situ
experiments to determine the role of fire in germination should be performed.

33. Neobeckia aquatica

Investigate the demography of fluctuating populations.
Determine critical life stages that may be influencing population
fluctuations.
Determine physical factors that may influence population fluctuation.
Studies of habitat preferences -- namely, pH requirements, optimal light
regimes, and requirements for sediment composition and nutrient levels --
should be undertaken.
Determine biotic interactions that may influence population
fluctuation. Biological interactions, including potential herbivore interactions
and the existence of symbiotic relationships, should be documented.

34. Panicum flexile

Study ecological interactions to determine how seed dispersal and
herbivory affect plant population structure.
Assess the plant’s response to natural and anthropogenic
disturbance.

35. Paronychia argyrocoma

Identify pollinators in at least three separate locations, one montane, one
along the Saco River, and the Massachusetts site.
Study limiting factors influencing dispersal, germination, and establishment
of successful reproductive populations would be valuable.

36. Pedicularis lanceolata

Study demography. At this time, no population viability analysis of
Pedicularis lanceolata has been performed, and so it is difficult to state
specific, quantitative conservation objectives for population sizes and
numbers of this taxon with any degree of confidence. Because P. lanceolata
is short-lived, is not self-pollinating, and is relatively late-flowering, large
populations may be required in order to maintain viability. Turnover rate in
short-lived species is greater than that in longer-lived species, and so more
plants are needed to allow for yearly fluctuations in survival rates. Species
that are not self-pollinating require enough other individuals within traveling
distance of pollinators to achieve pollination and seed set. Finally, plants that
are insect-pollinated and are late-flowering may need to be present in
enough abundance to meet the nutritional requirements of pollinators without
help from many other species.
Studies of another species of Pedicularis can provide some insight
into the issue of population size. A species with similar habitat requirements
and life history, Pedicularis palustris, inhabits "fen meadows" in Europe
(Schmidt and Jensen 2000) and wet soil in eastern Canada (Gleason and
Cronquist 1991: 487) and is becoming rare in some European countries.
Like P. lanceolata, it is short-lived and is primarily out-crossing (Macior
1993). In a single-year examination of 13 extant populations in Germany and
Norway, populations were shown to be highly variable, having between
three and 28,500 flowering individuals each (Schmidt and Jensen 2000). In
this species, larger populations were correlated with higher numbers of
capsules per plant and with higher numbers of seedlings per flowering plant.
Perform demographic studies of occurrences in parts of the country
where it is not endangered and to compare these with New England
populations. Potential differences in climate, vegetation, and pollinators must
be considered when applying results of such studies in New England.

37. Polemonium van-bruntiae

Quantify germination rate and seedling survival rate (some data
already exist from a previous introduction of plants into a new site in
Vermont)
Characterize demography (e.g., percent of new stems in a population per
year, average age of individual plants and age structure of population,
average age and range of ages at reproductive maturity, average and range
of number of seeds set, and average lifespan), the size of clones and the
genetic structure of populations (e.g., average number of ramets per genet
and genets per population); following marked individuals would be helpful,
and data obtained might allow researchers to model population viability.
Determine pollinators and pollination success (while bees have been
observed visiting some flowers, very little is documented about Appalachian
Jacob’s ladder pollination); percent seed set, and mechanisms of dispersal;
understanding these may be especially important for managing small
populations, like the one in Maine
Study habitat requirements (e.g., why is it rare, if it grows well in roadside
ditches?), especially light, tolerance for flooding and drought, and soil pH
and nutrient profile
Document effects of disease and herbivory
Genetic study. This plant has an unusual distribution, with several
occurrences in Vermont, and one disjunct population in Maine. A genetic
study could elucidate the origin and degree of isolation of this population,
and enable us to determine whether conservation is warranted or feasible at
this edge-of-range occurrence.

38. Polymnia canadensis

Research species ecology in New England. Recent studies of Polymnia
canadensis have been done regarding life history, germination, and
pollination (Bender 1991). These studies could provide a model for similar
studies in New England. Of particular interest may be a study of dispersal
and seedling requirements. It remains puzzling as to why so few sites exist in
New England where suitable habitat does not appear to be a limiting factor.

39. Pterospora andromedea

Collect data on phenology, size of inflorescences, spacing of
inflorescences (do they appear in "clumps"?), herbivory, seed
production and dispersal, persistence or reappearance of individual
plants at exactly the same location, and pollinator visits. Pollinator
identification is likely a crucial piece of missing information. Observation of
fungal associations will also be vitally important.
Analyze any and all available records of historic occurrences to shed
light on the causes of Pterospora’s decline in New England and almost
complete disappearance in New York. The broader the area of study, the
more likely it will be to yield evidence of causative factors, so, ideally,
records for the entire eastern population segment (from Michigan to Prince
Edward Island) should be examined. Wherever possible, field notes or
publications of collectors should be reviewed for any information about the
occurrences they collected. Mapping of historic occurrences and last
observation dates, when compared with land use history, could be especially
informative. Knowledge gained about causes of Pterospora’s decline in the
East may help in formulation of strategies for its recovery.
Conduct wider sampling and DNA analysis of Pterospora and its
associated mycorrhizae from sites throughout the eastern distribution
to determine which Rhizopogon species are parasitized by eastern lineage(s)
of Pterospora. Introduction, reintroduction, or augmentation of Pterospora
undoubtedly would require the presence of adequate populations of the
appropriate species of Rhizopogon mycorrhizal fungi at the chosen site. The
genus is taxonomically challenging (Kretzer et al. 2000, Bidartondo and
Bruns 2002), and very little is known about the distribution of Rhizopogon
species, especially in the East.

40. Rhexia mariana

Collect data on the population structure, life history, reproductive and
dispersal abilities, and habitat requirements of this species in New
England to inform future conservation decisions. Is Rhexia mariana limited
primarily by abiotic factors such as temperature, moisture, or soil nutrients,
or by competitive interactions with other plants? What are the competitive
abilities of this species? Which other plants are most likely to interfere with
its growth? How do changes in water levels on pond shores affect the health
of R. mariana populations and its competitors? Is pollen limitation a
problem for the reproduction of this species as it was for R. virginica in
Ontario?
Are the extant populations on Cape Cod are genetically independent
or form one or more metapopulations? This information would help
determine where introductions would be most beneficial and which would be
the best sources for seeds. Two extant EOs in Sandwich are about 0.5 km
apart, and five EOs in Brewster are each no more than 2 km from one of the
others, with one pair within 0.6 km and the other three within 0.8 km of each
other. Bumblebees occasionally range as far as 5 km from their nests
(Heinrich 1979, Goulson and Stout 2001), but a study of Rhexia virginica
populations in Ontario implied little genetic exchange between populations
only 400 m apart when separated by an arm of a lake (Larson and Barrett
1999a).
It may also be informative to make genetic comparisons between
New England representatives of the taxon and those from the center
of its range to determine if this peripheral population is evolving differently
from the rest of the species. Is there a genetic basis for the apparently
narrower habitat requirements of R. mariana in New England? Any
research that could help explain why the very similar Rhexia virginica is so
much more common on Cape Cod and extends farther north to Nova Scotia
and Ontario would also be useful.

41. Rhynchospora capillacea

Competition experiments may inform future management activities,
because competition is one of the primary threats to this species. Of
particular interest would be competition with other native calcareous wetland
species, such as Carex lasiocarpa, which is present in many fen
communities, and which increased in cover following water level rises caused
by beaver damming (Rawinski and Lapin 1990).
Research into population dynamics in response to disturbance could
provide important information that would inform management decisions. For
example, ecologists observed that the population of R. capillacea in
Egremont, Massachusetts produced new areas of fruiting and very robust
individuals in great numbers following a wildfire in 1999. This species may
respond to disturbance with an increase in sexual reproduction, which
enables it to establish new areas of a fen and populate the seed-bank. As it
is gradually out-competed by other, taller vegetation, the species may bide
its time along the fringes of pools, paths, and in the seed bank, awaiting
another disturbance event and reproductive opportunity. Research that
tested this, or other, hypotheses relating to population dynamics, would help
managers understand how best to increase population size at a given site.
Experiments to investigate seed germination requirements and
seedling establishment should be undertaken as soon as possible, in case
reintroduction of R. capillacea to a site is necessary in the future,. Longevity
of seed viability in storage should also be tested.
Population viability analyses (PVA) should occur for at least three
separate populations of R. capillacea in New England, preferably one for a
population in each of the three supporting community types. By conducting
such analyses, critical information may be gained about the actual viability of
our populations, including limits for minimum viable populations. These
studies will also help identify limiting life-history stages (Holsinger and
Gottlieb 1991).

42. Rotala ramosior

Observations on insect pollinators should be gathered from at least two
sites in New England, MA.011 (Holyoke) and CT .007 (Glastonbury).
Research and studies of the dispersal mechanisms for the taxon should also
be undertaken. The method of dispersal to new, distant locations is of
particular interest, as is the success of establishment at new locations.
Research on the viability of pollen and seed, the reproductive status
of populations, and the genetic diversity within and among New England
populations are needed and will assist in the conservation of the species in
the region.
Field observations and possibly research are needed to assess the
long-term threat of Lythrum biological control agents on populations
of R. ramosior. No intentional introduction any Lythrum biological control
agent should be undertaken in the vicinity of known extant occurrences.
However, if the beetles are observed feeding on Lythrum at any site
containing the taxon, immediate continued observations and studies should
be conducted to determine if any incidental or significant feeding on R.
ramosior is taking place. These studies should remain ongoing at any such
location in the long-term. Each occurrence of R. ramosior containing
Lythrum salicaria should be checked for the presence of biological control
agents each time it is surveyed.

43. Schoenoplectus etuberculatus

Genetic analysis of Schoenoplectus etuberculatus throughout its
range to determine the uniqueness of the Rhode Island population. This
study is considered the highest research priority for this species as analysis
might determine that the single New England population is genetically
distinct, and therefore a higher conservation priority.
Study of the relationship between water levels and plant
reproduction. Casual observations suggest the annual percentage of fruiting
stems in the Rhode Island population may be affected by fluctuations in
water levels. This assumption requires additional yearly assessment of
population productivity and tracking of water levels to identify conditions for
optimum production.
A review of the use of this species as food by waterfowl throughout
its range, including the Rhode Island location, may give some incite into the
potential pressure on populations caused by browsing.

44. Scirpus longii

Seed viability experiments should be conducted. I would recommend
burying nylon packets of seed in the wetland soil at known bulrush sites, and
retrieving some of the packets each year for viability/germination testing.
Factors that trigger fertile culm formation, such as fire, should be
investigated, especially in concert with water level monitoring.
Small-scale soil scarification experiments should be carried out to
determine whether seedlings germinate from the seed bank, or to see if
planted seeds (from that same population) germinate and mature.
The plant communities supporting Long’s bulrush require detailed
study in order to learn more about the community and habitat relations of
the species, and to detect and remedy subtle perturbations to these wetland
systems. In particular, we need to better understand the relationships
between the wetland vegetation and the nutrient status of the soils and water.
Hydrologic studies and fire history investigations would also greatly
help us understand these environments.

45. Sclerolepis uniflora

What is an individual plant? This species reproduces primarily
vegetatively; so are clumps of plants clones or is the entire population in a
lake a clone?
How should abundance be determined and reported?
What conditions stimulate terrestrial growth and flowering?
Can this species maintain itself in the aquatic form indefinitely?
Can it overwinter in terrestrial form?
When flowering, is pollen viable? Are seeds produced? Are seeds
fertile?
Why have seed not been found after flowering at one of the
populations?
Can Sclerolepis compete and coexist with the invasive aquatic plant,
Myriophyllum heterophyllum?
How do the peripheral populations of Sclerolepis compare with plants
from the rest of the range, since the New England occurrences are the
most northern populations? Are these two isolated northern populations
genetically variable or are they predominantly one clone? Are New England
plants genetically different from the rest of the range?
What is the range of variability in lake water levels, which maintain or
create suitable habitat for Sclerolepis? Can we obtain information on historic
water levels in Wallum Lake at the turn of the century? How does water
level affect flowering and seed set?
What environmental factors affect growth?
What effect will efforts to control or eradicate Myriophyllum
heterophyllum have on Sclerolepis?
What effect does lake liming have on Sclerolepis?
How does this species respond to disturbance from boating? To what
depth do these plants grow and what effect does boating have on the cutting
of fragments and the stranding of material on shore?

Field and greenhouse studies should be conducted on New England plants to
investigate the above questions. Additional information may be gained by
examinations of populations outside of New England.

46. Scutellaria integrifolia

Habitat requirements. Especially with regard to soil, light and disturbance,
in order to identify potential sites for surveys or introductions. Greenhouse
studies that manipulate soil texture (e.g., sand content, clay subsoil), soil
moisture (both variability and average levels), light availability, soil nutrient
levels (including variable levels in calcium), and reaction to growing season
disturbance (such as cutting), would help determine habitat requirements.
This would in turn aid in management of populations, identification of likely
areas for surveys and evaluation of sites for introduction. Studies would also
provide a baseline against which soil samples from potential introduction sites
could be compared.
Reproduction. Specifically about time of year seeds germinate; how long it
takes for plants to become reproductively mature; pollination; dispersal and
seed predation.
Distinct gene pools. Do plants grown from Connecticut wild seed differ
morphologically, biologically or ecologically, from each other, from New
York plants, or from those available from nurseries or other seed
collections? Does this indicate a need for or caution against outcrossing with
other populations?
Effects of drought. Does increased mortality or decreased reproduction
occur from prolonged or ill-timed drought?

47. Senna hebecarpa

Conduct research at several sites on insect interactions, pollination,
seed dispersal, longevity of individual plants, and response to
disturbance.
Study possible symbioses with nitrogen-fixing bacteria; are they
necessary for the species to grow?
Determine seed viability (cross-pollination, low genetic variability), and
seed longevity (to determine seed bank effectiveness).

48. Solidago rigida

Species survival and reproductive parameters: plant longevity,
pollination and seed set, and seedling recruitment. These factors could be
addressed through permanent marking and monitoring of individual plants,
through quantification of seed set followed by hand pollination if seed set is
found to be low, and by creating artificial experimental germination sites.
Soil preference. The dependence on calcareous or magnesian soil should
be investigated through soil testing of the current occurrences. If this
dependence turns out to be the case, that would indicate strong limitations on
where the plant could occur and would have implications both for de novo
searches and for considerations of introduction or reintroduction.
Tolerance of salt water flooding. Two of the three Connecticut sites are
on the coast, with the plants a few meters or less from the water's edge.
Given the possibility of hurricane flooding and sea level rise at these sites, salt
water injury is a consideration that could be tested experimentally at Garden
in the Woods or a similar facility where Solidago rigida ssp. rigidai is being
cultivated. The author does not recommend experimentally subjecting
existing wild populations to potentially lethal doses of sea water.

49. Stuckenia filiformis ssp. occidentalis

The taxonomic status of S. filiformis subsp. occidentalis should be
determined through modern molecular techniques, to ascertain if it is a
species or a hybrid. DNA analysis similar to that of Whittall et al. (in
preparation) or isozyme work similar to that conducted by Hollingsworth et
al. (1996a, 1996b) should be carried out. Plant material from related species
of Stuckenia, which may be involved in a possible hybrid, should be
obtained for analysis. These taxa include: S. filiformis subsp. alpina, S.
pectinata, and S. vaginata. A thorough study of all the Stuckenia in North
America would make an excellent Ph.D. dissertation.
Characterize the nature of competition between Stuckenia pectinata
and S. filiformis subsp. occidentalis where they co-occur.
Investigate the impacts of nutrient-loading on the establishment,
survivorship, and reproduction of S. filiformis subsp. occidentalis.

50. Taenidia integerrima

Investigate the effects of limited canopy removal and soil
scarification on seed bank germination, seedling establishment, and
reproduction of plants.
Determine how seeds of Taenidia integerrima disperse. Using this
information, strategies should be developed to promote dispersal of seeds to
new areas.
Research should specifically focus on whether seeds of Taenidia
integerrima can remain viable in the seed bank over time. Hyatt and
Casper (2001) used a protocol to understand between-year seed bank
persistence in temperate deciduous forest. Due to the rarity of New England
populations, manipulative seed bank studies that might negatively impact
these populations should be considered for sites outside of New England.

51. Triantha glutinosa

Study riverside seep habitats. Little is known either about the biology of
this species or the ecology of riverside seeps. Studies contributing to the
understanding of the ecology of this taxon are needed to understand the
mechanisms responsible for establishment, maintenance, and dispersal of T.
glutinosa occurrences as well as other species in the riverside seep
community.
Why is Triantha glutinosa not found in all areas along the river
shores?
Is flooding or ice scour more important to survival of the plants?
What is the minimum viable population size?
Studies to quantify the genetic isolation of the Connecticut and Maine
River populations would help guide conservation planning.

52. Triphora trianthophora

Determine optimal and acceptable light, moisture, and leaf litter and
soil conditions that optimize plant growth, survivorship, and reproduction.
Paired comparisons of beech-dominated sites that do and do not support
Triphora trianthophora may be informative. Although impacts from timber
harvest are generally viewed as negative for forest herbs, canopy thinning
may be appropriate in conditions that are thought to be too shaded.
Determine general light requirements for the orchid. Woody debris is also
known to be important for seed germination in certain orchid species
(Rasmussen and Whigham 1998); is it important to T. trianthophora?
Study mycorrhizal and saprophytic relationships. Because mycorrhizal
associations are likely to be crucial to the existence of the orchid, they should
be considered for study; studies on other orchids may provide insights as to
the importance of additional information for management and the costs to
populations of conducting such research (Taylor and Bruns 1997 and
Kristiansen 2000).
Describe pollination ecology, primary pollinators and rates of activity,
rates of outcrossing and inbreeding in populations.
Quantify seedling establishment.
Compare the relative contribution of vegetative and sexual
reproduction to population growth.
Quantify impacts of herbivory on plant survivorship and reproduction.

53. Trollius laxus

Test for the presence of a seed bank in populations with no fruit
production in a given year. Take small shovelfuls of soil in the vicinity of the
larger Trollius plants in late fall or early spring. Put some in flats outdoors
and keep moist until they freeze for the winter, and subject others to
treatment optimal for Trollius germination in cultivation (Brumback 1983).
Look for Trollius seedlings emerging in the spring and summer.
Alternatively, dry the soil samples, sieve, and search for seeds, then sow.
Determine the source and chemistry of water inputs to the wetlands
supporting Trollius, and ascertain whether these are groundwater discharge
wetlands. Locate records or collect data indicating periodicity and extent of
natural flooding.

54. Verbena simplex

Study pollination, fertilization, seed dispersal, germination rates and
seedling survival, responses to short-term climatic fluctuations, and
the taxon’s long-term viability in its present habitats. Comparison of this
regional information with similar studies in the central part of its range
(Kentucky, Missouri, and Oklahoma, for example), where the plant is
common, could shed light on the specific reasons for the rarity of Verbena
simplex in New England.
The influence of invasive species that colonize disturbed upland habitats
with a circumneutral soil base (Centaurea maculosa, for example), could
also be investigated as a possible limiting factor for the taxon’s viability in
New England. Has the proliferation of spotted knapweed and other
invasives minimized the potential for Verbena simplex to occupy open
communities that it could have colonized successfully a century or more ago?

Due date for proposals: February 5, 2003. Notification of Fellowships will be made in early March, 2003 

For more information, please contact: Elizabeth Farnsworth (508) 877-7630, ext. 3207 or email: efarnswo@mtholyoke.edu

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