Effects of soil compaction on the germination and survival of common prairie forbs and grasses in Wisconsin prairie revegetation

Abstract

Compaction of soil is a global issue that affects agricultural crops, agroforestry, and possibly restoration of native plant communities, which are often desired for roadside vegetation. We test the effects of soil compaction on the establishment and persistence of native forbs and grasses using a randomized complete block design with 4 replications at 2 sites in Wisconsin. Using a vibratory plate compactor, we created 4 levels of soil compaction in November 2011. A forb–grass mixture of species commonly used in Midwestern prairie restorations was seeded in November 2011 as a dormant seeding. Compaction in the top 10 cm (4 in) of soil and soil moisture were assessed at the time of seeding and during April and May 2012. Plant density and cover were measured in June of the establishment and survival years (2012 and 2013) for each planted species, with non-planted species cover assessed at the same intervals. Using linear regression we explored relationships between surface compaction and planted species density in the establishment year, and relationships between mean soil compaction and planted species density and cover, and non-planted species cover in the survival year. Soil compaction had no effect on species density in the establishment year. Soil compaction had a slight negative effect on forbs, a variable effect on grasses, and a slight positive effect on non-planted forbs in the subsequent year. Overall, soil compaction at levels similar to those observed on Wisconsin roadsides did not have a marked impact on germination and survival of the studied species.