Miscanthus 9 giganteus is a C 4 perennial grass that shows great potential as a high-yielding biomass crop. Scant research has been published that reports M. 9 giganteus growth and biomass yields in different environments in the United States. This study investigated the establishment success, plant growth, and dry biomass yield of M. 9 giganteus during its first three seasons at four locations (Urbana, IL; Lexington, KY; Mead, NE; Adelphia, NJ) in the United States. Three nitrogen rates (0, 60, and 120 kg ha À1 ) were applied at each location each year.Good survival of M. 9 giganteus during its first winter was observed at KY, NE, and NJ (79-100%), and poor survival at IL (25%), due to late planting and cold winter temperatures. Site soil conditions, and growing-season precipitation and temperature had the greatest impact on dry biomass yield between season 2 (2009)

Most turfgrass soil cultivation research has emphasized water in· filtration and thatch responses, but has provided limited information regarding detailed soil and rooting responses to different cultivation methods. This study evaluated cultivation effects on soil physical properties and turf growth of a 'Penneagle' creeping bentgrass (Agrostis palustris Hods.) putting green. Cultivation, utilizing vertically operating hollow (HTC) or solid (STC) tines, was applied over a 3-yr period on a loamy sand soil (modified fine-loamy, mixed, mesic, TypicDep. of Crop and Soil Sciences, Michigan State Univ., East Lansing, MI 48824. Acknowledgment is made to the U.S. Golf Association, the Michigan Turfgrass Foundation, and the Michigan Agric. Exp. Stn. for support of this research. Part of a thesis submitted by the senior author in partial fulfillment of the M.S. degree.

Frequency and severity of anthracnose epiphytotics, caused by Colletotrichum cereale Manns Manns sensu lato Crouch, Clarke, and Hillman, on annual bluegrass (ABG) [Poa annua L. f. reptans (Hauskins) T. Koyama] putting greens have increased over the past decade. This 3‐yr field study evaluated the impact of N fertilization (4.9 kg ha−1 every 7 or 28 d), mefluidide (ME; 0 and 0.106 kg a.i. ha−1 yr−1) {N‐[2,4‐dimethyl‐5‐[[(trifluoromethyl)sulfonyl]amino]phenyl]acetamide}, trinexapac‐ethyl (TE; 0 and 0.050 kg a.i. ha−1 every 14 d) [4‐(cyclopropyl‐α‐hydroxy‐methylene)‐3,5‐dioxocyclohexanecarboxylic acid ethylester], verticutting (VC; 0‐ and 3‐mm depth every 14 d), and interactions of these factors on anthracnose of ABG mowed at 3.2 mm. Nitrogen fertilization frequency had the greatest influence on disease throughout the study; N applied at 4.9 kg ha−1 every 7 d reduced damage 5 to 24% compared to a 28‐d interval. The plant growth regulators, ME and TE, frequently interacted during the last 2 yr of the study; sequential application of ME and TE reduced disease 6 to 14% compared to plots that only received one of these plant growth regulators. At advanced stages of disease, the combination of 7‐d N fertilization and ME and TE application had the greatest disease reduction. Verticutting had little effect on anthracnose severity.

No abstract

Cultivars and selections of Kentucky bluegrass (Poa pratensis L.) exhibit varying degrees of summer stress tolerance. Understanding the factors associated with performance under summer stress is important for identifying stress tolerant germplasm. The objective of this field study was to evaluate shoot and root growth responses of 10 Kentucky bluegrass genotypes subjected to high temperature and drought stress conditions in New Jersey. Turf canopy characteristics, shoot and root growth responses, and soil water depletion patterns were evaluated on a Nixon Loam (fine‐loamy, mixed mesic Typic Hapludult) and used to characterize Kentucky bluegrass selections having variable summer stress tolerance. Tolerant entries maintained 19% more roots at the 15‐ to 30‐cm depth in 1995 and 65% more roots at the 30‐ to 45‐cm depth than intolerant entries. Gravimetric soil water contents of tolerant plots were significantly lower at the 15‐ to 30‐cm depth than intolerant entries for both years. Tolerant Kentucky bluegrass, able to exploit deep soil moisture under heat and drought conditions, exhibited significantly fewer summer stress symptoms, had significantly lower stomatal resistance (based on subset of cultivars), and maintained canopy temperature 5°C cooler than intolerant entries at the end of stress periods. This indicated that maintenance of transpirational cooling was an important factor associated with better summer stress performance of turf plots under high temperature and drought conditions in New Jersey.