Thursday, August 19, 2010

An Interview with Dave Williams: Part 2

The Tallgrass Prairie Center Guide to Seed and Seedling Identification in the Upper Midwest makes identifying these little green sprouts look possible. Tell us what motivated you to write this book.
My greatest motivation for writing this book was to give anyone interested in growing tallgrass prairie plants the ability and confidence to identify prairie seedlings. It all started in 1998 when I was conducting graduate research at UNI. A major part of this research involved being able to identify prairie seedlings of 23 forb species. Only one prairie seedling identification book was available: Prairie Seedlings Illustrated by Laura Jackson and Lora Dittmer. This publication was very helpful but included only 12 of the 23 forbs that I needed to identify. So, as a winter project in 1999, I grew all 23 forbs in the UNI greenhouse. I sketched thousands of seedlings as they emerged and developed. I had to use a hand lens to find unique plant characteristics. I created a spreadsheet to organize the information in a way that I could use in the field. What I thought would be a short winter project took the entire winter and spring to complete.

Your guide focuses on 72 species. How did you select these?
I selected the species for this book based upon the following. First, species most likely to be used in a prairie planting. I have used all the species in this book in various seed mixes over the years. Second, availability of seed. Individuals can purchase seed of all species in this book from commercial sources. Third, species somewhat easy to propagate. Seed of most species included in this book can be germinated but may require additional treatments to maximize germination. Fourth, species that belong to important guilds of prairie species. A good example of a prairie guild is the legume species, species in the bean family that take nitrogen from the atmosphere and convert it to a form that plants can use. Legumes provide fertilization to the prairie. Fifth, species not listed as threatened or endangered. Some threatened and endangered prairie species have very specific habitats in the wild and may have unique genetic traits. From a conservation standpoint, it could be detrimental to remnant populations of threatened and endangered species if nonremnant plants are established all over the landscape.

What audiences did you aim for? Would a beginning gardener be able to use this guide?
Initially, I thought natural resource managers would use this guide to assess prairie plant establishment in conservation plantings. However, as this project evolved, I realized that anybody with an interest in planting tallgrass prairie could benefit from this guide. So the project began as a technical resource guide containing lots of botanical jargon and has been reworked many times to become a user-friendly guide. 

The illustrations present information so clearly. How did you come up with the format?
From day 1, my goal was to develop a system that a person without any seedling identification experience could use to identify prairie seedlings in the field. Common sense and botanical sense dictated the format. Dichotomous plant keys are time-tested tools that many botanists use to identify plants. While these keys are essential for plant identification, they require extensive botanical training to be effective. I used the dichotomous key format for my guide but simplified the number and extent of choices. The challenge was to distill what seemed like an infinite number of seedling characteristics into a small number of groups so users could differentiate seedlings of 72 species.

What was trickiest about growing and photographing the plants?
First, I had to define what was a seedling plant! My goal was to illustrate seedlings at the stage they might be found in a planted prairie near the end of the first growing season. This was somewhat of an arbitrary designation because seedlings can change in a few short weeks. Ultimately, determining the seedling stage of each species was based upon my observations of new prairie plantings over the last 20 years.

It became clear early on that the only way to photograph seedling plants and their associated parts was to grow them in a greenhouse from seed and grow many individuals for each species. Plants grow fast in the greenhouse and slow in the field. I found that most species needed only 4 to 5 weeks of greenhouse time after planting before they were similar to seedlings in the field at the end of the first growing season.

Photographing the small seedling plants was very challenging. David O’Shields and I experimented with exposures, light combinations, and backgrounds until we realized that we needed expert advice from someone experienced with macro photography. Jeffery Byrd of the UNI Art Department graciously volunteered his time and expertise to help us get the exposure and lights right. Positioning the seedlings on the stage was very time-consuming. Heat from the lights caused the seedlings to bend and curl, which added another level of complexity. Sometimes aphids crawled along the plant and interfered with the photograph. I suspect we took 30 to 40 photographs of each species. 

Dave Williams, The Tallgrass Prairie Center Guide to Seed and Seedling Identification in the Upper Midwest

No comments:

Post a Comment