Research in Botany

Dr. Don Mansfield engages C of I students in a botanical discussion

Current Projects

Students working at the Harold M. Tucker Herbarium are currently engaged in a wide variety of original research projects. They are making real and relevant contributions to our knowledge of plant taxonomy, biogeography, plant genetics, and a host of other botanical disciplines. Each project will culminate -- or already has culminated -- in a professional research presentation at the very least, and many will result in research papers published in peer-reviewed journals. The projects and researchers profiled below are just a cross-section of the vibrant research climate at the Herbarium.

Soil-based endemism in plants of the Owyhee region

Researcher: Brittni Brown, a senior Environmental Studies major with minors in Spanish and in Analytical and Technical Skills in the Natural Sciences, has studied abroad in Costa Rica. After graduation, she plans to pursue an advanced degree in conservation biology and a career in habitat restoration, working to develop conservation solutions that strike the best balance between the needs of the local people and those of threatened ecosystems.

Project:In the Owyhee region of southwest Idaho and southeast Oregon, there is an abundance of rare and unique plants; many of these species are associated with particular soils, especially with beds of ancient volcanic ash. The details of the relationship between these plants and their native soil is often unclear, though. This summer and fall, Brittni gathered plant population data and soil samples from eight ash-bed sites across the Owyhees. She is currently analyzing the soil samples and the plant distribution, and has won a Student Research Grant to have the soil samples' cation exchange rates examined at an external laboratory.

Morphological and genetic analyses of the rare endemic mustard Lepidium papilliferum

Researcher: Laura Barbour, a senior Environmental Studies major with a conservation biology focus, became involved with the herbarium by working with Dr. Mansfield in the summer of 2010. She has been working on her Lepidium project for the past two years; collecting data for the project has given her great opportunities to interact with botanists, conservationists, and Fish and Wildlife staff. After graduation, she plans to earn a Master’s degree in a natural-resources-related field and pursue a career in conservation.

Project: Slick spot peppergrass, Lepidium papilliferum, is a rare species in the mustard family. It is found only in southwestern Idaho, and then only in tiny “slick spot” habitats scattered among the sagebrush steppe. Laura is investigating the genetics and morphology of this endemic plant, trying to determine how greatly slick spot peppergrass differs both between far-flung populations and from its closest relatives. She is also analyzing the species’ ecology, seeking to identify the environmental factors that shape each slick spot peppergrass population. Her overarching goal is to understand Lepidium papilliferum’s phylogeny—how its different populations have diverged from each other over time.

Investigation in Astragalus morphology

Researcher: Betsaida Chavez Garcia is a senior Environmental Studies major with a conservation biology focus and a Spanish Foundations minor. She enjoys being outdoors, and became interested in botany after taking Dr. Mansfield’s Field Botany course in her sophomore year. After graduation, she plans to pursue an advanced degree in plant ecology.

Project: The woolypod milkvetch, Astragalus purshii, is a highly variable species, with at least five taxonomic varieties in CIC’s collections alone. The lines between these varieties are frequently blurred and uncertain. Betsaida’s work deals with A. purshii var. ophiogenes (the Snake River milkvetch) and A. purshii var. lagopinus. She is working to determine whether these plants actually belong to two separate varieties, to one more-variable variety, or to an entirely new variety as yet unknown to science. Secondarily, she also plans to study the reasons for these differences—the ecological and genetic factors that drive changes in the plants’ morphology and distribution.

Available Projects

Students looking for an exciting, rewarding research experience need look no farther than the Harold M. Tucker Herbarium. There are always new studies to be done and new questions to be answered. A few of the potential projects in need of more investigation, just waiting for a researcher, are summarized below.


Working with Dr. Mansfield, this project would involve gathering genetic data on populations of plants from the field. There are several plants, including Primula cusickiana, and Lepidium spp. for which the taxonomy is unclear and genetic data are needed to bring clarity to the taxonomic groups. If you like to perform eletrophoretic separations and analyze gels to determine degrees of inter and intrapopulational genetic variation, then this work would be right up your alley.


In southwestern Idaho and southeastern Oregon there are many plant species that are poorly known. In some cases there are collections of plants that appear to be somewhat distinct from existing species. In some cases these differences may appear to be minor and not worthy of any new name. In other cases the differences may warrant new names, that is, they may be species or subspecies new to science. Without careful examination of many populations of plants, represented by many specimens in the Tucker Herbarium, it is difficult to know what are the appropriate boundaries of a particular species. By studying the morphologic variation (let alone the genetic, chemical, or other forms of variation) among many collections that have been acquired over the past few decades by students, faculty, and friends of the Tucker Herbarium it is possible to hypothesize new taxonomic boundaries for our local taxa. There are many taxa that would benefit from multivariate, morphometric analysis of existing herbarium specimens. A study of this sort could be done in one or more semesters without extensive field study using resources available in the Tucker Herbarium. The goal of such a study would be to understand species boundaries in one of these "problematic" taxa.