Sod‐Seeding of Ladino Clover and Alfalfa as Influenced by Seed Placement, Seeding Date, and Grass Suppression1

Abstract

AbstractThe competition between a grass sward and a legume seedling limits legume growth when sod‐seeding legumes into perennial grass swards. The objective of this research was to evaluate the effects of time of seeding, grass suppression, and seed placement on the spring establishment of ladino clover (Trifolium repensL.) and alfalfa (Medicago sativaL.) in a tall fescue (Festuca arundinaceaSchreb.) sod. Field experiments were conducted during 4 years (1978 to 1981) on a Cecil clay loam soil (clayey, kaolinitic, thermic Typic Hapludult) in North Carolina. Seeds were drilled or placed on the soil surface with and without broadcast applied paraquat (1, 1'dimethyl‐ 4, 4′‐bipyridinium ion) at 0.28 kg a.i. ha−1on two dates (mid‐February or mid‐March) in a randomized complete block design with a 2 ✕ 2 ✕ 2 factorial arrangement. Legume stands and dry matter yields were measured. Drilling legume seeds vs. surface placement resulted in two to four times as many seedlings initially established and up to 2000 kg ha−1more legume yield during the first season. Nevertheless, satisfactory stands were eventually obtained from surface seeding ladino in late February in 3 of 4 years. Planting in February resulted in better stands and yields of clover than March plantings in 3 of 4 years. Using paraquat for sod suppression often resulted in significant advantage when clover was seeded at the later (March) date. Alfalfa produced very low yields during the first season under all treatment variables (usually one or two harvests) and did not appear to compete well with the tall fescue sod when spring seeded. The highest yields obtained during these studies ranged from 795 to 4610 kg ha−1.