No‐Till Seeding of Red Clover into Tall Fescue as Influenced by Grass Suppression, Fungicide, and Nutrients

Abstract

No‐till planting of red clover (Trifolium pratense L.) is recommended for improving the nutritive quality and seasonal production of endophyte‐infected tall fescue (Festuca arundinacea Schreb.) but fungal diseases can cause stand and yield losses. The objective of this research was to determine the effect of grass suppressant, fungicide, and nutrients (P and K) on red clover no‐till planted in September during 3 yr. Six field experiments were conducted in the northern Georgia limestone valley area near Calhoun, and in the Southern Appalachian mountains near Blairsville. ‘Redland III’ red clover was no‐till planted in September using factorial combinations of the following treatments to examine their effect on first year stand and forage yield: paraquat herbicide, vinclozolin [3‐(3,5‐ dichlorophenyl)‐5‐ethenyI‐5‐methyl‐2,4‐oxazolinedione] fungicide, and nutrients (50 lb P205/acre and 50 lb K2O/acre). No‐till planting of red clover with no sod treatment resulted in first‐year tall fescue‐red clover dry forage yields (3‐yr average) of 7380 lb/acre, of which red clover comprised about 50%. Sod suppression or nutrients alone had no effect (P > 0.05) on clover stands or yield. Monthly fungicide application alone increased (P < 0.05) red clover yields 120% in 1 out of 3 yr. Suppressant + fungicide increased (P < 0.05) yield 44% over the check in 2 out of 3 yr. Fungicide + suppressant + nutrients increased (P < 0.05) yields over that of the check with a 3‐yr average increase of 75% at the two locations. The higher yields obtained with fungicide, grass suppressant, and nutrients over 3 yr at two locations suggest that disease losses in no‐till planted red clover may be over 40%. Research Question No‐till seeding of red clover into grass sods is generally more dependable than alfalfa because of better seedling vigor. However, red clover losses occur that are mainly a result of fungal diseases such as crown and stem rot caused by Sclerotinia trgoliorum. The present study evaluated the effects of grass suppression, fungicide application, and nutrients (P and K) on establishment and yield of September no‐till seeded red clover at two north Georgia locations. Literature Summary No‐till seeding of red clover in grass during late summer and autumn in the mid‐Atlantic and lower midwestern states of the USA often results in serious stand and yield losses from crown and stem rot. The impact of crown and stem rot and other diseases on stand and forage yield of red clover no‐till seeded in autumn has not been determined in the southeastern USA. Grass suppression is necessary for successful no‐till seeding of alfalfa but its usefulness in red clover establishment may be questionable. Study Description Six field experiments were conducted over 3 yr at Blairsville (2200 ft elevation) and Calhoun (640 ft) in northern Georgia. ‘Redland III’ red clover was no‐till planted in mid‐September and paraquat grass suppressant, vinclozolin fungicide, and nutrients (P and K) were applied alone and in all combinations to compare red clover stand and...