Cypripedium Acaule Research Articles

Plant reintroduction in restored peatlands: 80% successfully transferred – Does the remaining 20% matter?

In ecological restoration, especially in projects aiming at introducing a diverse plant community, species that do not establish are rarely reported., Yet, knowledge gained from identifying and understanding the reasons why species did not establish is useful to improve restoration techniques. In this paper, we used Sphagnum dominated peatlands restored with the Moss Layer Transfer Technique (MLTT) as a typical example of restored ecosystems for which information about species that does not establish is lacking. By comparing the plant species pools of 22 pairs of donor/restored Sphagnum peatlands (including 17 sites restored for more than 10 years), we calculated that the proportion of successfully introduced plant species (transfer rate) was 82 ± 9%, amongst the highest transfer rate when compared to other restoration projects. Only five vascular plant species were classified as recalcitrant – species present in the donor site but absent from the restored sites: Carex trisperma, Cypripedium acaule, Ilex mucronata, Maianthemum trifolium and Rubus chamaemorus. Explanations about the filters impeding establishment were mainly based on the autoecology of the species. Depending on restoration goals (e.g. return of edible berries or orchid diversity) we recommend the specific reintroduction of recalcitrant species after the MLTT.

Geography and soil chemistry drive the distribution of fungal associations in lady’s slipper orchid,Cypripedium acaule

Mycorrhizal associations are required for the germination of orchids in nature. Recent studies reveal that distributions of arbuscular mycorrhizal and ectomycorrhizal fungal species are influenced by soil nutrient availability. However, it is unclear how soil nutrient availability influences mycorrhizal and root endophytic fungal association in orchids. Here we studied the pink lady’s slipper Cypripedium acaule Aiton, an orchid found typically in Pinus L. dominated forests of eastern North America, which associates with a diverse suite of fungi. We sampled 16 C. acaule populations across central and northern Georgia, USA. Soil samples were collected at the site of each plant and analyzed for organic matter, total carbon and nitrogen, calcium, ammonium, nitrate, and pH. Fungi present in the roots of each plant were identified from root samples using DNA analysis of key fungal barcoding genes. We then assessed the degree to which fungal associates corresponded to particular geographic, climatic, and soil factors via nonmetric multidimensional scaling. Our results indicate a broad association between geography, soil chemistry, and the distribution of root endophytic fungal associations in C. acaule. Importantly, this association may help explain why orchids with broad fungal associations are rare within landscapes. However, further research on the role of fungal availability in the soil is warranted.

Orchids of Atlantic Coast Barrier Islands from North Carolina to New York

During the past 25 years, we have documented the occurrence of 17 orchid species from Atlantic coast barrier islands from North Carolina to New York, including Calopogon tuberosus, Corallorhiza wisteriana, Cypripedium acaule, Epipactis helleborine, Goodyera pubescens, Habenaria repens, Listera australis, Malaxis spicata, Platanthera cristata, Pogonia ophioglossoides, Spiranthes cernua, S. lacera var. gracilis, S. laciniata, S. odorata, S. praecox, S. vernalis, and Tipularia discolor. For each species, we present data on localities of extant orchid populations, fluctuations in population size, flowering dates, habitat preferences, threats to some populations, results of herbarium and literature searches, and our opinion on the status of orchid species reported by others but not observed by us in the field. Spiranthes vernalis is the most common orchid on mid-Atlantic coast barrier islands. Other species occurring in large (> 1000 individuals) populations include Platanthera cristata, Spiranthes cernua, S. praecox, and Tipularia discolor. Four orchid species occur in moderately large (50 to 100 individuals) populations but have limited distributions, including Calopogon tuberosus, Cypripedium acaule, Epipactus helleborine, and Pogonia ophioglossoides. When analyzed by locality, several regions of high orchid diversity can be identified, including False Cape, Virginia, and the region between and including Nags Head Woods and Kitty Hawk Woods on Bodie Island, North Carolina. These orchid “hot spots” occur in regions that provide a high diversity of habitats.

Early response of the herbaceous layer to harvesting in a mixed coniferous–deciduous forest in New Brunswick, Canada

We studied plant communities before and after two types of clearcutting to determine their response and their relationships to disturbance intensity and to make management recommendations. Permanent plots sampled before and for 2 years after harvesting were used to compare changes in the herbaceous layer for 2 years after harvest in three treatments: clearcutting with natural regeneration (C), clearcutting with mechanical site preparation and planting (CS) and uncut control (UC). The greatest compositional changes occurred in the CS treatment, where 16 species were lost and 20 new species were gained compared to 14 lost and 16 gained in the C treatment. The number of forest habitat species decreased 20–24% by the second year after harvest in both treated areas. Species that were lost included Cypripedium acaule, Monotropa hypopithys, Orthilia secunda, Ribes lacustre, Streptopus amplexifolius, Thelypteris noveboracensis and Vaccinium vitis-idaea. The number and cover of disturbance-adapted species increased about 250% in the CS treatment compared to 200% for the C treatment. Mean total species richness per plot, Shannon–Wiener, Simpson and evenness diversity indices were significantly greater ( P<0.05) the second year after harvest than before harvest in the two harvest treatments. Richness of forest species significantly declined in both treated areas. Sørensen’s similarity index (each post-harvest year versus pre-harvest) increased with time in all treatments and was lowest in the CS treatment. Cover of most growth forms, especially bryophytes, decreased after harvesting in the two harvest areas, whereas small trees/shrubs and graminoids increased, particularly in the CS treatment. Cover of conifer seedlings and bryophytes greatly decreased in the C treatment where coniferous stand types dominated before harvest. Four non-native taxa ( Plantago major, Ranunculus acris, Taraxacum officinale and Veronica officinalis) were encountered in the study. In 1997, total cover of non-natives was 0.2% in the CS treatment and <0.05% in the C and UC treatments. We conclude that the more dramatic changes in species composition and diversity in the CS treatment are the result of greater forest floor disturbance caused by site preparation. Protection of forest understory plants can be improved by minimizing forest floor disturbance, maintaining shade cover and leaving uncut strips or patches in areas containing species that are sensitive to harvesting.

Cost of reproduction in the pink lady's slipper orchid (Cypripedium acaule, Orchidaceae): an eleven‐year experimental study of three populations

An 11-yr experimental study of the cost of reproduction in three wild populations of the perennial orchid Cypripedium acaule contrasted experimental plants that were repeatedly hand-pollinated and often made fruits with control plants that were not hand-pollinated and only rarely made fruits. Repeated flowering without subsequent fruit production resulted in no detectable reduction in either plant size or probability of flowering in subsequent years. A cost of fruit production was evident in experimental plants in all three populations in terms of a reduced probability of flowering and smaller leaf area in subsequent years, but was not evident in terms of mortality rate. Experimental effects of fruit production reached maximum values at 3-7 yr, depending on the population. The probability of remaining dormant below ground in a given year was strongly dependent on plant size in the previous year. Furthermore, the length of the dormancy period (one to several years) was a significant and inverse function of plant size just prior to dormancy. Sample sizes and the consequent ability to detect experimental effects declined over time as more plants died or stopped flowering. Four to seven years appears to be an optimal duration for studies of the cost of reproduction in perennial herbs similar to this species. Studies lasting less than 4 yr may be too brief to reveal experimental effects, whereas those lasting more than 7 yr may fail to reveal new insights.

MALE AND FEMALE POLLINATION SUCCESS IN A DECEPTIVE ORCHID, A SELECTION STUDY

We carried out phenotypic selection analyses to assess the relative importance of several floral traits, as well as microhabitat, in determining both male and female pollination success in a nonrewarding orchid (Cypripedium acaule Ait.) in two Nova Scotia populations. Fruit production in these one-flowered, cosexual plants was strongly pollen limited within a season: 100% of individuals set fruit following hand-pollination, but only 5% and 13% did so under natural circumstances in the two populations. Male and female reproductive success were highly correlated, with >90% of plants that received a pollinium also dispersing one. Despite very low visitation rates, the chance of a removed pollinium fertilizing another ovary was 36% and 51%, respectively, in the two populations. There was no evidence for selection acting differently, either through the two sexual functions or in the two populations. In contrast, the strength of directional selection on several traits differed among microhabitats within each population. Univariate and multivariate regressions indicated statistically significant directional selection acting on flower-opening date through male, female, and total (combined) pollination success in one population. For female, male, and total success in this population, we also detected correlational selection acting on opening date and flower height. There was also negative correlational selection acting on flower height and labellum length through female success. Microhabitats within the populations had a larger effect on both female and male success than did floral traits. In particular, the presence of ericaceous shrubs and an open canopy appeared to be closely linked with higher pollination rates.

Morphogenèse comparée de protocormes du Cypripedium acaule (Orchidaceae) cultivés in vitro avec ou sans sucre

Seeds of the terrestrial orchid Cypripedium acaule from temperate regions contain an undifferentiated embryo consisting of about one hundred cells. These cells contain lipid and protein storage reserves. The development of the seeds was studied in vitro on a germination medium with or without dextrose (glucose). On the medium containing dextrose, proembryos develop and form a protocorm. From the anterior pole of the protocorm appears a "promeristem", a structure that will form a scale and the apex of the seedling. The formation of the root never precedes that of the apex. In the protocorm, the amount and size of starch grains show an increasing antero-posterior gradient. Only the apex, the procambium, and the secretory cells do not accumulate starch grains. On the medium without dextrose, the proembryos develop slowly into a protocorm, and a semi-meristematic region can be recognized at the anterior pole. However, no other tissue differentiation occurs and the protocorm soon degenerates without having undergone organogenesis. The protocorm accumulates a few starch grains, more voluminous and more numerous at the posterior pole, that agglomerate around the nucleus; but during the development, these rapidly disappear from the cells. Generally, all cells are strongly vacuolated. These observations indicate that orchid seeds cannot reach the seedling stage without a sugar input, which is ensured by a fungal symbiont in nature. Key words: Orchidaceae, morphogenesis, protocorm, starch, sugar effect, in vitro germination.

Costs of Reproduction in the Pink Lady's Slipper Orchid (Cypripedium acaule): Defoliation, Increased Fruit Production, and Fire

An earlier experiment with the pink lady's slipper orchid demonstrated that plant leaf area was lowered only after successive years of increased fruit production. This result suggested that the cost of reproduction was small in relation to the energy budget of the plant. To test this idea, plants were subjected to experimental hand-pollination treatments to increase fruit set as well as leaf removal treatments to decrease the energy budget of plants. Changes in plant size in years 2 and 3 and, to some extent, rate of flowering, were determined by a combination of initial plant size, leaf removal treatments in year 1, fruit production in year 1, and damage from an unplanned fire in year 2. Plants that had both leaves removed and produced a fruit in 1987 decreased in size in the following 2 years in comparison with other treatment groups. The cost of fruit production was not apparent in plants that had only one or no leaves removed. Plants apparently have to be put into severe physiological stress in order for a cost of reproduction to appear in the following year. The cost of producing one fruit was a decline of plant size in the following year of 30 cm2, which is very similar to our previous experiment using a different design. An additional experiment failed to find evidence that these plants increase their photosynthetic rate to compensate for the loss of leaves or the cost of maturing fruit. Published experiments in both the greenhouse and the field that failed to find a cost of reproduction should be reevaluated in terms of the intensity of treatment imposed and the overall energy budget of the plant in field situations.

Costs of reproduction in the pink lady's slipper orchid (Cypripedium acaule): defoliation, increased fruit production, and fire

An earlier experiment with the pink lady's slipper orchid demonstrated that plant leaf area was lowered only after successive years of increased fruit production. This result suggested that the cost of reproduction was small in relation to the energy budget of the plant. To test this idea, plants were subjected to experimental hand‐pollination treatments to increase fruit set as well as leaf removal treatments to decrease the energy budget of plants. Changes in plant size in years 2 and 3 and, to some extent, rate of flowering, were determined by a combination of initial plant size, leaf removal treatments in year 1, fruit production in year 1, and damage from an unplanned fire in year 2. Plants that had both leaves removed and produced a fruit in 1987 decreased in size in the following 2 years in comparison with other treatment groups. The cost of fruit production was not apparent in plants that had only one or no leaves removed. Plants apparently have to be put into severe physiological stress in order for a cost of reproduction to appear in the following year. The cost of producing one fruit was a decline of plant size in the following year of 30 cm2, which is very similar to our previous experiment using a different design. An additional experiment failed to find evidence that these plants increase their photosynthetic rate to compensate for the loss of leaves or the cost of maturing fruit. Published experiments in both the greenhouse and the field that failed to find a cost of reproduction should be reevaluated in terms of the intensity of treatment imposed and the overall energy budget of the plant in field situations.

Simple Methods for Calculating Age‐Based Life History Parameters for Stage‐Structured Populations

Stage—classified matrix models are important analytical and theoretical tools for the study of population dynamics; in particular, these models may be appropriate for populations in which survivorship and fecundity are dependent on size or developmental stage, populations in which the age of individuals is difficult to determine, and populations in which there are multiple types of newborns. Nevertheless, methods for analyzing the implications of a population's stage—transition matrix have been limited in comparison to methods available for age—structured models (life tables or Leslie matrices). In this paper we show that all of the standard age—based measures of life history traits can be derived from a stage—transition model. By decomposing the transition matrix into separate birth, survival, and fission matrices we derive simple, direct formulas for age—based life history traits such as the discrete survivorship function, lx, maternity function, fx, mean age at maturity, and net reproductive rate, Ro, and also population parameters, including the stable age distribution, age—specific reproductive value, and generation time. These provide a common set of parameters for comparing age—structured and stage—structured populations or comparing populations with differently structured life cycles. In addition, we define four measures of age and life—span that summarize the relationship between stage and age in a stage—structured population: age distribution and mean age of residence for each stage class, expected remaining life—span for individuals in each stage class, and total life—span conditional on reaching a given stage class. We illustrate the use of our methods to address specific ecological questions by applying them to several previously published demographic data sets. These questions include: (1) what are the demographic effects of crowding on the tropical palm Astrocaryum mexicanum?; (2) how important is the initial rosette size in determining life history of teasel, Dipsacus sylvestris?; and (3) how old are reproducing adults in a stage—classified population of pink lady's—slipper, Cypripedium acaule? Our results may also be useful for evaluating the adequacy of a given stage—transition model.

Platanthera pallida (Orchidaceae), a New Species of Fringed Orchis from Long Island, New York, U.S.A.

Reexamination of the species and hybrids of the simple-lipped group of the genus Platanthera sect. Blephariglottis shows that several colonies found on eastern Long Island constitute a new species. Platanthera pallida is described based upon its recurved lip, reflexed lateral sepals, cream coloration, and unusual habitat-dry, interdunal hollows. It was previously referred to as P. because of its superficial resemblance to that species and lack of other similar fringed orchises in the northeastern United States. Platanthera pallida P. M. Brown, sp. nov. TYPE: United States. New York: Long Island, Suffolk County, Montauk, C. S. Bryan, 10 Aug. 1948 (holotype, AMES 65176). Figure 1. Platantherae cristatae (Michaux) Lindley similis, sed ab ea perianthio in alabastro perpallide aurantiaco post anthesin eburneo, labello recurvato ligulato fimbriato, petalis obovatis ad apicem fimbriatis, fimbriis plerumque furcatis, calcari obtuso 5-6 mm longo, sepalo medio integro, sepalis lateralis valde reflexis differt. Plants (20-)29-65(-84) cm tall, glabrous and distinctly glaucous; lower leaves 2-3, sheathed, strongly keeled, conduplicate, to 25(-30) cm long and 3(-5) cm wide when flattened; upper leaves reduced to 3-5 linear bracts below the inflorescence. Inflorescence racemose, (18-)24-80(-112)-flowered, (5-)10-20(-27) cm long, 2.5-4 cm diam., densely flowered except in very tall individuals; lower floral bracts usually equal to or often exceeding the pedicellate ovary and decreasing in length upward, about 2.2 cm long. Perianth very orangeyellow in bud opening to cream, petals and lip often aging to a deeper creamy yellow or fading to a dull white; lateral sepals 3 mm long, 3 mm wide, reflexed, widest at the middle and tapering to a rounded apex and truncated base; dorsal sepal 3 mm long, 3 mm wide, concave, entire and arching forward to partially enclose the fringed petals; petals obovate, 3.25 mm long, 2 mm wide, fringed at the tip, the fimbriae usually forked and clearly visible to the sides of the dorsal sepal; lip ligulate, 3 mm long, 2 mm wide (exclusive of fringe); recurved or, rarely, descending, the margin with forked fimbriae up to 3 mm long, the fimbriae near the base perpendicular to the lip; spur 5-6 mm long, tubular, NOVON 2: 308-311. 1992. strongly curved, either obtuse or bulbous at the tip; nectary orifice T-shaped; column with the viscidia 2.5-3 mm apart; fruit a capsule, 1-1.6 cm long. Illustration. Photograph in Rickett (1966: plate 20) as Habenaria cristata. Distribution and ecology. Currently known only from the Town of East Hampton, Suffolk County, Long Island, New York. Plants growing in dry, interdunal hollows and dune slopes (but never swales); usually with Pinus rigida, Quercus velutina, Cladonia sp., Smilax glauca, S. rotundifolia, Toxicodendron radicans, Hudsonia ericoides, Danthonia sp., Agrostis sp., Minuartia caroliniana, Arctostaphylos uva-ursi, Vaccinium corymbosum, and Cypripedium acaule. Etymology. The term pallida, pale, is chosen for its appropriate description in comparison to P. (Michaux) Lindley and other brightly colored, related species. In the past, these plants have commonly been called the pale cristata or pale fringed orchis. The latter is recommended for a

Costs of Reproduction in the Pink Lady's Slipper Orchid: A Four-Year Experimental Study

The cost of current reproduction on future growth, survival, and reproduction is a central concept in evolutionary ecology, but the field evidence in plants for a cost of reproduction is weak because the appropriate experimental protocol (manipulation of the level of reproduction in an experimental group of individuals) has rarely been carried out. The pink lady's slipper orchid, Cypripedium acaule, is well suited to this design because naturally occurring flowering plants only rarely fruit, whereas virtually all hand-pollinated flowers develop into fruits. In two eastern Massachusetts populations, plants were randomly assigned to be hand-pollinated or left as controls, with the treatments repeated in four successive years. After 2 yr, treatment effects were weak at one site and absent from the other site. By the third and fourth years, the high cost of reproduction was clearly demonstrated in a lower growth and flowering rate of hand-pollinated plants in comparison with the control plants. An average-sized plant that produces a fruit in the current year results in an estimated 10%-13% decrease in leaf area and a 5%-16% decrease in the probability of flowering in the following year. Plants that are experimentally defoliated are still capable of maturing their fruit, even though these plants have a decreased probability of flowering in the following year. These results show that long-term studies in the field are capable of demonstrating a cost of reproduction.

The reproductive biology of boreal forest herbs. II. Phenology of flowering and fruiting

The flowering and fruiting phenologies of 12 boreal forest herbs were recorded during 1979 (flowering and fruiting) and 1980 (flowering only) in spruce–fir forests of central New Brunswick. The species studied were Aralia nudicaulis, Chimaphila umbellata, Clintonia borealis, Cornus canadensis, Cypripedium acaule, Linnaea borealis, Maianthemum canadense, Medeola virginiana, Oxalis montana, Pyrola secunda, Trientalis borealis, and Trillium undulatum. Flowering in the community occurred from mid-May to the end of July. The order of flowering was maintained in the 2 years, but the degree of synchronization of inflorescences differed in several species. Fruiting in the community began in mid-July and extended beyond the end of September. The percentage of buds that ultimately bore fruit ranged from 0 (Cypripedium acaule) to 61% (Aralia nudicaulis). With the exception of Cypripedium acaule, which received little pollinator service, the self-incompatible species, Cornus canadensis, Maianthemum canadense, and Medeola virginiana, experienced the lowest levels of fruit-set. Pollen limitation and predation of developing fruit appear to be the major factors limiting percentage fruit-set in boreal forest herbs. Fruit production varied with time of flowering of inflorescences in several species, with periods of low fruit-set tending to coincide with lower densities of flowering inflorescences. Significant rates of fruit removal by herbivores occurred in all sarocochorous species. Disappearance of fruits from infructescences ranged from 31 (Medeola virginiana) to 95% (Aralia nudicaulis), with highest removal rates occurring during periods of greatest fruit availability.

The reproductive biology of boreal forest herbs. I. Breeding systems and pollination

Detailed observations and experimental studies of the reproductive biology of 12 boreal forest herbs were conducted over a 3-year period (1978–1980) in spruce–fir forests of central New Brunswick. The species examined were Aralia nudicaulis, Chimaphila umbellata, Clintonia borealis, Cornus canadensis, Cypripedium acaule, Linnaea borealis, Maianthemum canadense, Medeola virginiana, Oxalis montana, Pyrola secunda, Trientalis borealis, and Trillium undulatum. All taxa are insectpollinated perennials and most exhibit clonal growth. Floral syndromes of the understory community are relatively unspecialized with many species possessing small white or green flowers. A total of 103 taxa of insects were collected from flowers during the 1979 season. Bombus spp. are the major pollinators of 5 of the 12 species. Syrphid flies, bee flies, and halictid and andrenid bees were also commonly observed. Controlled pollinations were undertaken to determine the breeding systems of herbs. Bagged, self-, cross- and open-pollinated treatments were used to investigate the capacity for self-pollination, compatibility status, and factors influencing fecundity in each species. A diversity of reproductive systems was revealed. Six species are completely dependent on insects for pollination, four species are weakly autogamous, one is strongly autogamous, and one appears to be apomictic. Comparisons of fruit-set and seed set from controlled self- and cross-pollinations indicate that four species are strongly self-compatible, one is dioecious, and the remainder display varying degrees of self-incompatibility. Despite this variation, outbreeding appears to be the most common reproductive mode. In several species there is evidence that low pollinator service limits fruit-set.

Effects of disturbance by visitors on two woodland orchid species in Great Smoky Mountains National Park, USA

Two species of woodland orchid, showy orchis Orchis spectabilis, and pink lady slipper Cypripedium acaule, were surveyed for population density, clumping characteristics, and shoot morphology along sampling routes with easy, moderate and difficult access for visitors in Great Smoky Mountains National Park. Showy orchis populations were denser close to trails, and there were no major differences in populations attributable to visitor disturbance. The density of lady slipper populations was not clearly related to road or trail position, but there were significant differences in plant morphology between, easy, moderate and difficult access routes and some morphological characteristics gave significant regressions against road and trail distance. There was only limited evidence that environmental factors, such as slope or elevation, were influencing shoot morphology. The results indicate that visitors to the National Park will have difficulty finding blooming plants, despite the numerous lady slipper shoots along easy access routes. Rare plant monitoring efforts and further plant poaching studies should include detailed morphological information, since density may not be an adequate measure of population condition.

POLLEN REMOVAL IN CYPRIPEDIUM ACAULE (ORCHIDACEAE) IN RELATION TO AERIAL FENITROTHION SPRAYING IN NEW BRUNSWICK

AbstractMeasures of pollen removal in the orchid Cypripedium acaule Ait. provided a retrospective method for estimating the activity of bumble bee pollinators in New Brunswick spruce-fir forests. Significantly lowered activity was observed in fenitrothion-sprayed forest as compared with unsprayed control areas. The difference is probably attributable to direct mortality of bees in sprayed forest.

Detachment (Elimination) of Chromosomes in Cypripedium acaule

Detachment (Elimination) of Chromosomes in Cypripedium acaule