Organic amendments decrease bulk density and improve tree establishment and growth in roadside plantings

摘要: Abstract Soil compaction significantly impacts urban tree survival and herbaceous vegetation recruitment along roadsides. samples were collected at two highway planting sites in Ontario, Canada. The average soil bulk density the 0–10 20–30 cm range was 1.45 g cm−3 1.55 g cm−3, respectively, Site 1. At site 2, 1.49 g cm−3 1.67 g cm−3, respectively. Six treatments established on each to determine amount of organic amendment required decrease increase growth as a measurement successful establishment. Compost incorporated into 0%, 10%, 25% 50% volume-to-volume basis both sites. In 2014 Acer x freemanii Autumn Blaze® ‘Jeffersred’ whips planted treatment bed (Site 1, n = 36 2 n = 42). Bulk density, porosity, pH, EC, survival, height, shoot extension chlorophyll content measured for 2015 growing seasons. Incorporation v/v compost consistently decreased below-root restricting thresholds, resulting improved growth. Significant differences observed between organic-amended remediated beds compared control; higher (p