Turf Response to Urease Inhibitors and Cationic Materials Applied in Combination with Urea

We evaluated the response of Kentucky bluegrass (Pea pratensis L.) turf to urea amended with the urease inhibitors PPD, NBPT, and ATS and with the cations K+ (KCl) and Mg+2 (MgCl2). Treatments for the 2-year field experiment included liquid urea applied monthly in June to Sept. 1985 and 1986 at 49 kg N/ha with PPD (1%, 2%, 3% by weight of applied N), NBPT (0.5%, 1%, 2%), ATS (5%, 15%, 25%), K+ (5%, 15%, 25%), and Mg+2 (5%, 15%, 25%). The NBPT was included only in the 1986 field study. The Mg+2 and K+ reduced foliar burn and increased turf quality during mid- and late Summer 1985 at the 5% rate, but clipping yield was not affected by any treatment. In 1986, under milder climatic conditions, PPD and NBPT increased clipping yield by 13.2% and 15.2%, respectively. At the 15% rate, ATS increased clipping yield by 15.1%, but, on average, PPD and NBPT were much more effective. Chemical names used: phenylphosphorodiamidate (PPD), N-(n -butyl) thiophosphoric triamide (NBPT), and ammonium thiosulfate (ATS).

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Fall Application of Prodiamine for Spring Crabgrass (Digitaria spp.) Control

Weed Technology ◽

10.1017/s0890037x00039774 ◽

1994 ◽

Vol 8 (3) ◽

pp. 612-616 ◽

Cited By ~ 3

Author(s):

Thomas W. Fermanian ◽

Jean E. Haley

Keyword(s):

Field Study ◽

Weed Control ◽

Kentucky Bluegrass ◽

Quality Loss ◽

Turf Quality ◽

Fall Application

Fall application of a PRE herbicide offers professional lawncare applicators additional flexibility in scheduling necessary weed control operations. A 3-yr field study was established on common Kentucky bluegrass in Urbana, IL to examine the effectiveness of fall- or spring-applied prodiamine and DCPA for spring large and smooth crabgrass control. Prodiamine was effective for crabgrass control in turf (≥ 91% control) when applied in spring at ≥ 0.4 kg/ha or when it was applied in the fall at ≥ 0.6 kg/ha (≥ 82% control). In most cases, fall-applied prodiamine at the 0.8 kg/ha rate (≥ 91% control) controlled crabgrass as well as spring-applied DCPA at the 11.8 kg/ha rate (≥ 94% control). Little reduction in turf quality (≥ 8.3) occurred when prodiamine was applied in the fall at 0.8 kg/ha or less. Only when prodiamine was applied at 2.2 kg/ha was there significant quality loss (7.3) with spring applications. In a second experiment to evaluate split fall and spring prodiamine applications for crabgrass control, all split applications had 100% crabgrass control which was not significantly different from single applications of ≥ 1.4 kg/ha.

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Timing the Establishment of Kentucky Bluegrass : Perennial Ryegrass Mixtures for Football Fields

HortScience ◽

10.21273/hortsci.43.1.240 ◽

2008 ◽

Vol 43 (1) ◽

pp. 240-244 ◽

Cited By ~ 5

Author(s):

John C. Stier ◽

Eric J. Koeritz ◽

Mark Garrison

Keyword(s):

Perennial Ryegrass ◽

Poa Pratensis ◽

Late Summer ◽

Kentucky Bluegrass ◽

Rust Disease ◽

Turf Quality ◽

Seeding Date ◽

Field Plots ◽

Species Proportions ◽

Seed Mixtures

Sports field construction contracts in cool-season areas often stipulate a 9- to 12-month period between seeding and opening for play. Seed mixtures are usually dominated by slow-establishing Kentucky bluegrass (KBG; Poa pratensis L.) and contain lower proportions of perennial ryegrass (PRG; Lolium perenne L.) for quick cover. Our objective was to evaluate the effect of planting time on three KBG : PRG mixes, a 100% PRG blend, and their ability to sustain football-type traffic. Field plots were seeded in late summer, as a dormant planting in late fall, and in the following spring. Plots received simulated football traffic, split for one or four weekly games, from mid-August through mid-November of the year in which spring seeding occurred. The experimental design was a strip-split-plot, randomized block with four replications. The study was repeated a second year. All seeding dates provided acceptable turf quality regardless of seed type by September. However, summer seedings of KBG-based mixtures provided better turf quality than mixtures planted in the spring, whereas dormant-seeded mixtures provided the poorest turf quality. Turf seeded with 100% PRG was less sensitive to seeding date, with summer or spring seedings providing similar quality and dormant seedings superior to KBG-based dormant seedings. Summer seedings also resulted in the least amount of broadleaf weeds the next year with dormant seedings having the most weeds, particularly with plots seeded to 95% KBG. All KBG-based seed mixtures provided turf containing ≈50% KBG or more by September, although the amount of KBG remaining after traffic was significantly greatest in plots seeded to 95% KBG and least in plots seeded with 70% KBG. Pure PRG swards provided acceptable turf quality throughout the traffic period but should be used cautiously as a result of winterkill potential and crown rust disease (Puccinia coronata Corda f. sp. agropyri Erikss.). Different amounts of traffic did not affect turf species proportions. The most consistently desirable results may be obtained with a mixture containing 70% to 80% KBG and 30% to 20% PRG, respectively. Mixtures dominated by KBG should be seeded in late summer for best results.

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Effect of urease inhibitors and cationic materials on growth response and ammonia volatilization following fertilization of Kentucky bluegrass (Poa pratensis L.) with urea

10.31274/rtd-180813-10630 ◽

1987 ◽

Author(s):

Young Kyoo Joo

Keyword(s):

Growth Response ◽

Ammonia Volatilization ◽

Poa Pratensis ◽

Kentucky Bluegrass ◽

Urease Inhibitors ◽

Cationic Materials

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Species Succession and Turf Quality of Tall Fescue and Kentucky Bluegrass Mixtures as Affected By Mowing Height

Crop Science ◽

10.2135/cropsci2013.10.0669 ◽

2014 ◽

Vol 54 (3) ◽

pp. 1220-1226 ◽

Cited By ~ 5

Author(s):

Stefano Macolino ◽

Guido Pignata ◽

Maurizio Giolo ◽

Michael D. Richardson

Keyword(s):

Tall Fescue ◽

Kentucky Bluegrass ◽

Species Succession ◽

Turf Quality

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Planting Date Affects Survival and Height Growth of Hybrid Poplar

The Forestry Chronicle ◽

10.5558/tfc62164-3 ◽

1986 ◽

Vol 62 (3) ◽

pp. 164-169 ◽

Cited By ~ 10

Author(s):

Edward A. Hansen

Keyword(s):

Hybrid Poplar ◽

Late Summer ◽

Growing Season ◽

Climatic Conditions ◽

Planting Date ◽

Planting Dates ◽

Soil Frost ◽

Growing Seasons ◽

Poplar Cuttings ◽

Energy Plantations

In this study I investigated the effects of planting date for soaked versus unsoaked cuttings of two hybrid poplar clones under irrigated versus unirrigated and weedy versus weed-free conditions. Cuttings were planted each year for 4 years. Survival at the end of the first growing season was generally greater than 90% for all planting dates. At the end of the second growing season survival for trees planted before July 16 was again generally more than 90%. However, cuttings planted from July 30 through August 27 showed a major decline in survival and survival of fall planted cuttings ranged from 6 to 90%. Mortality of late summer- or fall-planted cuttings occurred prior to the beginning of the second growing season and was attributed to frost heaving. The tallest trees were not those planted at the earliest possible dates (April in Rhinelander). Instead, the tallest trees at the end of the first and second growing seasons were those planted in early- and mid-May. This optimum planting period was the same regardless of clone, soaking, irrigation, or weed treatment. Actual optimum planting date would change with location and local climatic conditions. Some climatic indices may prove more universal in predicting when to plant. Although tentative, it appears that for best growth, unrooted hybrid poplar cuttings should be planted in soil warmer than 10 °C. Trees do not grow as well if planted immediately after soil frost leaves the ground. Key words: Energy plantations, plantation establishment, woody biomass, intensive culture, Populus.

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Salt Stress-induced Injury is Associated with Hormonal Alteration in Kentucky Bluegrass

HortScience ◽

10.21273/hortsci12413-17 ◽

2018 ◽

Vol 53 (1) ◽

pp. 97-101 ◽

Cited By ~ 3

Author(s):

Xunzhong Zhang ◽

Wenli Wu ◽

Erik H. Ervin ◽

Chao Shang ◽

Kim Harich

Keyword(s):

Salt Stress ◽

Cell Membrane ◽

Poa Pratensis ◽

Membrane Damage ◽

Kentucky Bluegrass ◽

Zeatin Riboside ◽

Cool Season ◽

Cell Membrane Damage ◽

Turf Quality ◽

Isopentenyl Adenosine

Plant hormones play an important role in plant adaptation to abiotic stress, but hormonal responses of cool-season turfgrass species to salt stress are not well documented. This study was carried out to investigate the responses of hormones to salt stress and examine if salt stress-induced injury was associated with hormonal alteration in kentucky bluegrass (KBG, Poa pratensis L.). The grass was grown in a growth chamber for 6 weeks and then subjected to salt stress (170 mm NaCl) for 28 days. Salt stress caused cell membrane damage, resulting in photosynthetic rate (Pn), chlorophyll (Chl), and turf quality decline in KBG. Salt stress increased leaf abscisic acid (ABA) and ABA/cytokinin (CK) ratio; reduced trans-zeatin riboside (ZR), isopentenyl adenosine (iPA), and indole-3-acetic acid (IAA), but did not affect gibberellin A4 (GA4). On average, salt stress reduced ZR by 67.4% and IAA by 58.6%, whereas it increased ABA by 398.5%. At the end of the experiment (day 28), turf quality, Pn, and stomatal conductance (gs) were negatively correlated with ABA and ABA/CK ratio, but positively correlated with ZR, iPA, and IAA. Electrolyte leakage (EL) was positively correlated with ABA and ABA/CK and negatively correlated with ZR, iPA, IAA, and GA4. GA4 was also positively correlated with turf quality and gs. The results of this study suggest that salt stress-induced injury of the cell membrane and photosynthetic function may be associated with hormonal alteration and imbalance in KBG.

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Effects of Compost Topdressing on Turf Quality and Growth of Kentucky Bluegrass

Applied Turfgrass Science ◽

10.1094/ats-2006-0113-01-rs ◽

2006 ◽

Vol 3 (1) ◽

pp. 0 ◽

Cited By ~ 9

Author(s):

G. A. Johnson ◽

Y. L. Qian ◽

J. G. Davis

Keyword(s):

Kentucky Bluegrass ◽

Turf Quality

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Control of Annual Bluegrass (Poa annua) in Kentucky Bluegrass (Poa pratensis) Turf with Linuron

Weed Technology ◽

10.1017/s0890037x0003637x ◽

1992 ◽

Vol 6 (4) ◽

pp. 852-857 ◽

Cited By ~ 10

Author(s):

J. Christopher Hall ◽

C. Ken Carey

Keyword(s):

Field Experiments ◽

Poa Pratensis ◽

Stand Density ◽

Normal Growth ◽

Dry Weight ◽

Kentucky Bluegrass ◽

Controlled Environment ◽

Annual Bluegrass ◽

Turf Quality ◽

Severe Reduction

Effects of linuron on annual bluegrass control and Kentucky bluegrass cultivar tolerance were studied in field and growth chamber experiments. In controlled environment experiments, linuron at 0.06, 0.12, 0.25, 0.50, and 0.75 kg ai ha-1 was applied to pure stands of annual bluegrass and eight Kentucky bluegrass cultivars. Linuron at the two highest rates controlled annual bluegrass, reducing the clipping dry weight by more than 85% 4 wk after treatment, and by 65 to 92% 6 wk after treatment. Growth of Kentucky bluegrass was reduced with the most severe reduction occurring 2 wk after linuron application. All cultivars exhibited normal growth 8 wk after treatment. In field experiments, linuron at rates from 1.5 to 2.0 kg ai ha-1 controlled annual bluegrass in old (> 5 yr) Kentucky bluegrass stands, and in 16 cultivars of 1-yr and 2-yr-old Kentucky bluegrass stands, with little or no damage. At rates of 1.5, 2.0, and 2.5 kg ai ha-1 linuron, damage to newly seeded cultivars was moderate to severe. However, 6 to 7 wk after linuron application to newly seeded cultivars, stand density and turf quality were equivalent to untreated checks.

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Reproduction affects flight activity in female and male Daubenton’s bats, Myotis daubentoni

Canadian Journal of Zoology ◽

10.1139/z07-045 ◽

2007 ◽

Vol 85 (5) ◽

pp. 653-664 ◽

Cited By ~ 22

Author(s):

M. Dietz ◽

E.K.V. Kalko

Keyword(s):

Energy Demand ◽

Late Summer ◽

Climatic Conditions ◽

Flight Activity ◽

Adult Males ◽

Reproductive Condition ◽

Small Individual ◽

Pregnant Females ◽

Pregnancy And Lactation ◽

Lactating Females

Nearly all mammals in the temperate zone breed in spring and summer when climatic conditions are favourable and food is abundant. Similar to other mammals, food requirements of female bats are particularly high during pregnancy and lactation and of males during spermatogenesis. Seasonal changes in energy demand and reproductive condition should therefore result in different foraging activity within and between sexes. This assumption was tested on 16 adult females and 13 adult males of the Palaearctic Daubenton’s bat, Myotis daubentoni (Kuhl, 1817), that were radio-tracked during pregnancy, lactation, and post-lactation periods. Pregnant females, as hypothesized, flew significantly longer (mean: 358.9 min; 70% of the night length) than males (mean: 228.5 min; 42.4% of the night length) during spring. In contrast, nightly flight time of lactating females decreased and was significantly less than that of pregnant females, but was similar to that of males during the same period. The longest flight times of males were registered during late summer when spermatogenetic activity is high. However, there were distinct differences in the use of foraging areas between female and male Daubenton’s bats. Female bats used small, individual foraging areas during pregnancy and lactation. The pattern was reversed in females after the young had been weaned and in males after they entered spermatogenesis. Overall, the results confirmed our proposition that flight activity reflects the higher energy demand and nutrition requirements in the different reproductive periods.

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