Barry R. Stewart

Preemergence Herbicide Effects on Hybrid Bermudagrass Root Architecture and Establishment

Determine the effects of commonly used PRE herbicides on hybrid bermudagrass root architecture and establishment. Introduction Hybrid bermudagrass (Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt-Davy) is commonly produced as sod in the southern US and other warm-season climates around the world. Preemergence herbicides are sometimes used to control annual weeds. However, these herbicides may negatively affect hybrid bermudagrass establishment from sprigs and/or sod. Preemergence Herbicide Effects on Hybrid Bermudagrass Root Architecture and Establishment Erick G. Begitschke, James D. McCurdy, Te-Ming (Paul) Tseng, T. Casey Barickman, Barry R. Stewart, Christian M. Baldwin, Michael P. Richard, and Maria Tomaso-Peterson Mississippi State University

Nitrogen and Sprigging Rate Effects on ‘Latitude 36’ Hybrid Bermudagrass Establishment

Hybrid bermudagrass [Cynodon dactylon · Cynodon transvaalensis] is frequently used throughout the southern and transitional climatic zones of the United States. These grasses can only be vegetatively propagated, such as by sprigging. Turfmanagers will often apply high rates of sprigs and nitrogen (N) in an attempt to minimize the time to establishment. However, little is known about how planting and N rates affect establishment. The objective of this study was to determine optimum sprigging andN rates during the establishment of ‘Latitude 36’ hybrid bermudagrass to minimize time to full surface cover. The study was conducted in four locations across the southern United States during Summer 2015. Sprigging rates consisted of 200, 400, 600, and 800 U.S. bushels/acre (9.3 gal/bushel), andN rates were 0, 11, 22, and 44 lb/acreN per week. Results showed that as the N rate increased, percent cover generally increased but only slightly [7% difference between high and low rates 5 weeks after planting (WAP)]. The effect of sprig rate on percent cover indicated that as rate increased, cover also increased. Differences in establishment due to sprig rate were present until 6 WAP at which time all plots achieved 100% cover. The greatest difference betweenN and sprig rate was that sprig rate showed differences in percent cover immediately, whereas N rate differences were not apparent until 2 WAP. Increasing sprig rather than N rate should be considered to speed up establishment.

Maximizing 'Cimarron' Little Bluestem Establishment as Secondary Rough for a Golf Course

Native grasses are an important design component in secondary roughs of golf courses due to minimal maintenance requirements and aesthetics. However, problems with seed germination and subsequent establishment limit their use. Two 2-year studies on ‘Cimarron’ little bluestem were conducted in 2000 and 2002 at Mississippi State University. In each study, seed was planted at five rates: 12.7, 25.4, 38.1, 51, and 63.4 lb of pure live seed (PLS) per acre. Visual percent cover was recorded each month after planting (MAP). The seeding rate of 12.7 lb PLS/acre may not be acceptable for secondary roughs, since coverage was only 6.7 and 4%, respectively, at 2 MAP. This would most likely result in establishment failure during rainfall events. By the end of the first 2-year trial, there were no significant differences among coverage rates ≥ 25.4 lb PLS/acre. By the end of the second 2-year study, there was no difference among seeding rates. Based upon this study, rates at or above 25.4 lb PLS/acre would be recommended. Though these higher ‘Cimarron’ seeding rates benefit first year establishment, 100% cover is still unlikely and establishment will require a minimum of 2 years. Early management response to weed competition may be a key component for successful establishment of ‘Cimarron’ little bluestem in golf course secondary roughs.