Restoration Ecology of an Endangered Plant Species: Establishment of New Populations of Cirsium pitcheri

Abstract

We determined the effects of shade, burial by sand, simulated herbivory, and fertilizers on the survival and growth of artificially planted population of Cirsium pitcheri -an endangered plant species of the sand dunes along Lake Huron. Sand burial experiments showed that greenhouse grown plants should optimally be transplanted into areas receiving 5 cm of sand deposition: burial at this depth maximized emergence, survivorship, and below-ground biomass. Under field conditions, simulated herbivory of up to 50% of the plant height produced a slight increase in biomass after one year of growth. Field observations showed that when white-tailed deer removed more than 50% of the transplant's leaf tissue, the plant died. The application of a 20:20:20 (N:P:K) water-soluble fertilizer produced a significant increase in the dry leaf biomass, total leaf area, and total dry biomass relative to control plants. We also tested for the presence or absence of a persistent seed bank. Few seeds were recovered from soil samples collected from Pinery Provincial Park and Providence Bay. However, C. pitcheri has the ability to form a persistent seed bank under field conditions but only at soil depths of у 15 cm. Cirsium pitcheri seeds are able to germinate and seedlings can emerge from a burial depth of up to 6 cm. Thus, seeds planted in open, sunny areas will probably maximize emergence, growth, and survivorship of seedlings. Populations of C. pitcheri can be restored by planting seeds at shallow depths, transplanting greenhouse-grown plants, applying water soluble fertilizers, and protecting plants from herbivores.

Population viability analysis and the effects of light availability and litter on populations of Cirsium pitcheri, a rare, monocarpic perennial of Great Lakes shorelines

“…Decreased light levels and the presence of litter reduced seedling emergence of C. pitcheri by 14-34% in our growth chamber experiment. These results corroborate those of Rowland and Maun (2001) who showed that C. pitcheri germination and seedling vigor are reduced by shade in the field. The negative impact of shade on plant survival and growth has been shown for other monocarpic perennials (Gross, 1984) and Lake Michigan dune taxa (Lichter, 2000).…”

“…We expressed F ij fecundity for C. pitcheri as a measure of seedling recruitment, defined as the number of seedlings per reproductive plant in the previous year (F 14 = n (seedling, t+1) /n (adult, t) ). Pitcher's thistle lacks a significant seed bank (Rowland and Maun, 2001); thus, this transition was not included as part of our demographic modeling. We also constructed ternary diagrams to compare the WSP population to other reports for C. pitcheri populations and related species (Silvertown et al, 1996;Bell et al, 2003).…”

The Ecological Characteristics of Seed Germination and Seedling Establishment of <i>Manglietia patungensis</i>: Implication for Species Conservation

“…In an experiment about the factors affecting seedling survival, Carol found that shade conditions affected early survival, and the death of seedlings of six species in nine species contributed to pathogens infection [40]. To ensure that rare and threatened flora extinctions be prevented or at least minimized, numerous attempts have been made to create new populations of endangered plants by translocation [41,42]. A successful translocation can be defined by addressing four goals of abundance, extent, resilience and persistence [43].…”

The influence of contemporary and historic landscape features on the genetic structure of the sand dune endemic, Cirsium pitcheri (Asteraceae)

“…obs.). It appears to have a very short-lived seed bank (Loveless, 1984;McEachern, 1992;Bowles and McBride, 1996;Hamzé and Jolls, 2000), which is unlikely to contribute significantly to population growth (Rowland and Maun, 2001).…”