Dissertations and Theses @ UNI

Availability

Open Access Thesis

Keywords

Prairie restoration--Middle West; Prairie plants--Middle West--Planting time; Prairie plants--Middle West--Growth;

Abstract

The conversion of the Midwestern United States’ tallgrass prairies to agriculture has resulted in extensive habitat loss and degradation and a decline in the provisioning of ecosystem services. To restore these services the United States Department of Agriculture created the Conservation Reserve Program (CRP) which provides incentives to agricultural landowners to implement conservation practices designed to meet goals pertaining to single ecosystem services. We studied the effects of seed mix design, planting time, and first-year management on the multifunctionality and cost-effectiveness of prairie reconstructions. We established research plots planted with one of three seed mixes either in the dormant (fall) or spring season with or without first-year mowing management applied. The Economy mix had a 3:1 grass-to-forb ratio consisting of 21 species, the Diversity mix had a 1:1 grass-to-forb ratio with 71 species, and the Pollinator mix had a 1:3 grass-to-forb seeding ratio containing 38 species. We measured native species richness, stem density, canopy cover, canopy fill, and floral resources in each plot over two growing seasons. We also estimated the cost-effectiveness of each seed mix at producing 1000 native stems. Additionally, we compared the effects of seed mix design and mowing management on vegetation outcomes across two sites differing in planting year and cropping history (soybeans versus corn) but sharing a similar experimental design. We found that the Economy mix established the highest number of grasses and native cover but the fewest forbs. The Pollinator mix had the highest number of forb stems and inflorescences but fewest grasses, whereas the Diversity mix established the greatest species richness, an intermediate density of grass stems, comparable forb stems and the highest floral richness. Mowing accelerated native species establishment and increased cost-effectiveness across all seed mixes. Spring planting had a strong influence on the establishment of warm-season grasses,while dormant plantings increased cool-season grasses and spring and fall forbs. The effects of seed mix design and first-year mowing on vegetation outcomes were robust across the two sites. Our results suggest CRP could effectively consolidate multiple existing conservation practices by instead recommending a diverse, evenly-balanced seed mix to provide multifunctional stands. We also recommend first-year mowing as an effective tool to accelerate plant establishment and dormant season planting as no cost approach to increase pollinator habitat quality.

Year of Submission

2021

Degree Name

Master of Science

Department

Department of Biology

Department

Tallgrass Prairie Center

First Advisor

Mark C. Myers, Chair

Date Original

5-2021

Object Description

1 PDF file (vii, 65 pages)

Language

en

File Format

application/pdf

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