Nitrogen fertilizer and clover inclusion effects on the establishment of fine fescue taxa

Little information exists on establishment vigor differences among fine fescue taxa (Festuca L. spp.) and on the effects N fertilizer levels or clover (Trifolium L. spp.)-inclusion during establishment. Five replicated field experiments in Indiana, Minnesota, and Oregon were conducted from 2019 to 2021. Data collection continued for 9 mo after planting to investigate differences among four fine fescue taxa and determine optimal N fertility or clover-inclusion programs for the establishment of fine fescue taxa. Six N fertilizer levels ranged from 0 to 122.5 kg N ha⁻¹ during the 8 wk after planting, and two treatments included clover-inclusion + 0 kg N ha⁻¹ at seeding. The three taxa of the Festuca rubra complex—strong creeping red fescue (F. rubra L. ssp. rubra Gaudin), slender creeping red fescue [F. rubra ssp. littoralis (G. Mey.) Auquier], and Chewings fescue (F. rubra ssp. commutata Gaudin)—were similar to one another and required the shortest amount of time until 90% establishment (i.e., faster establishment) compared with hard fescue (Festuca brevipila Tracey). Providing 24.5 kg N ha⁻¹ at seeding hastened establishment of all fine fescues compared with no N fertilizer (0 kg N ha⁻¹). Applying 49 kg N ha⁻¹ at establishment provided faster establishment than the 24.5 kg N ha⁻¹ treatment; however, treatments receiving 73.5–122.5 kg N ha⁻¹ during the first 8 wk after planting provided a similar rate of establishment as 49 kg N ha⁻¹. Inclusion of clover with fine fescue resulted in slower establishment than fertilizer levels of ≥24.5 kg N ha⁻¹.