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Abstract

A series of studies was conducted during 2 years with various environmental and management conditions to investigate the effect of herbicides on rooting of Kentucky bluegrass (Poa pratensis L.). Benefin at 2.2 and 3.4 kg·ha−1, pendimethalin at 1.7 and 3.4 kg·ha−1, and DCPA at 11.8 and 16.8 kg·ha−1 inhibited rooting when tillers were grown in tubes in a greenhouse. Inhibition was greater in the upper 14 cm of the profile than deeper down. Prodiamine at 0.6 and 1.1 kg·ha−1 consistently reduced clipping weights and verdure. However, none of the treatments inhibited rooting in the field in the two years of the study. Chemical names used: N-butyl-N-ethyl-2,6-dinitro-4-(trifluoromethyl)benzenamine (benefin); dimethyl 2,3,5,6-tetrachIoro-1,4-benzenedicarboxylate (DCPA); (±)-2-[4-[(6-chloro-2-benzoxazolyl)oxy]-phen-oxy]propanoic acid (fenoxaprop); N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine (pendimethalin); N3,N 3-di-n-propyl-2,4-dinitro-6-(triflouromethyl)-m-phenylenediamine (prodiamine).

Open Access
Authors: and

Abstract

This study was conducted to determine if the rate of ‘Meyer’ zoysiagrass (Zoysia japonica Steud.) establishment and spread could be enhanced when plugs were introduced into plant growth regulator-(PGR) treated Kentucky bluegrass (Poa pratensis L.) and perennial ryegrass (Lolium perenne L.) turfs. During the first growing season, PGR treatment made little difference in zoysiagrass spread. Zoysiagrass coverage in perennial ryegrass treated with mefluidide (57%) or amidochlor (63%) was significantly greater than in ryegrass treated with ethephon (47%) or the untreated control (48%) by the end of the 2nd year. Enhanced zoysiagrass spread in perennial ryegrass treated with mefluidide and amidochlor was attributed to stand thinning resulting from PGR phytotoxicity and environmental stress in the first year. Zoysiagrass coverage in Kentucky bluegrass was greatest in mefluidide-treated plots, but the increase over the control was only 6%. Flurprimidol slowed the establishment of zoysiagrass in both cool season turfs. Chemical names used: [(N-[(acetylamino)methyl]-2-chloro-N-(2,6-diethyl phenyl)acetamide (amidochlor); (2-chloroethyl)phosphonic acid (ethephon); α-(l-methylethyl)-α-[4-(trifluoromethoxy)phenyl]-5-pyrimidinemethanol (flurprimidol); and N-[2,4-dimethyl-5-[[(trifluoromethyl)sulfonyl]amino]phenyl]acetamide (mefluidide).

Open Access

Abstract

‘Sparkle’ and ‘Honeoye’ strawberries (Fragaria × ananassa Duchesne) were planted into plots of newly seeded perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), winter wheat (Triticum aestivum L.), or no grass. After a 1985 windstorm during the green fruit stage, yield was higher in living mulch plots than in control plots and fruit from control plots were small and dark relative to those from the ryegrass plots. In 1986, all plots had similar yields. All plants grew at similar rates during the establishment year. Later, strawberry plants in living mulch plots had smaller leaves than plants in control plots. Plants in all treatments contained above the critical concentrations of leaf N on most sampling dates. Soil under grass was less compacted and was cooler than cultivated soil. Living mulch prevented annual weed establishment after the first and improved winter survival of flower buds. A tillering type of ryegrass was the best living mulch of the three species tested. It quickly covered the ground but did not spread into the crop rows, and grew tall enough to afford wind protection.

Open Access

Abstract

The depletion of N applied to a moderately N-deficient Kentucky bluegrass (Poa pratensis L.) turf was measured using a soil sampling procedure. Nitrogen as either Ca(NO3)2 or (NH4)2SO4 was applied in solution at 5 g N/m2 and washed into the thatch and soil with an additional 0.3 cm of water. Both N forms were located primarily in the thatch and upper 1 cm of soil. The NO 3 was present in the soil solution, while the NH 4 + was mainly exchangeable (86%). The concentrations of NO 3 and NH 4 + in the soil solution were 452 and 56 μg N/ml, respectively, in the upper 1 cm of soil. Depletion of both NO 3 and NH 4 + from the turf was very rapid, with 70% to 80% of the applied N disappearing during the first 24 hr. Essentially all of the applied N was depleted by 48 hr. Results using (l5NH4)2SO4 indicate that ≈75% of the NH 4 + depletion is attributable to absorption by the turf. Similar results were obtained following fertilization of perennial ryegrass (Lolium perenne L.), tall fescue (Festuca arundinaceae Schreb.), and creeping bentgrass (Agrostis palustris Huds.).

Open Access

Abstract

‘Baron’ Kentucky bluegrass (Poa pratensis L.), ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.), and ‘Reliant’ hard fescue (Festuca ovina var. duriuscula L. Koch.) were treated with N-[2,4-dimethyl-5-[[(trifluromethyl) sulfonyl] amino] phenyl] acetamide (Mefluidide) at 0.28 and 0.56 kg/ha, (2-chIoroethyI) phosphonic acid (ethephon) at 2.24, 4.48; and 6.72 kg/ha; and 5-(4-chIorophenyl)-3,4,5,9,10-pentaaza-tetracyclo [5,4,1,02’6, 08,11] dodeca-3,9-diene (BAS 106 00 W) at 1.68, 3.36, and 5.04 kg/ha. Similar responses to all rates of mefluidide and BAS 106 00 W, and to the 2.24 kg/ha rate of ethephon were observed for Kentucky bluegrass and hard fescue. Tall fescue shoot growth was reduced by mefluidide and the BAS 106 00 W, but to a lesser extent than the other 2 species, and was not affected by ethephon. Ethephon elongated internodes and shortened leaf blades of Kentucky bluegrass. Ethephon at 2.24 kg/ha reduced Kentucky bluegrass clipping weight and increased root organic matter production without reducing quality.

Open Access

Abstract

Stripe smut [Ustilago striiformis (West.) Niessl.] is a destructive disease of ‘Merion’ and several other cultivars of Kentucky bluegrass [Poa pratensis L.). Fungicides (all in kg·ha-1) were foliar-applied to a diseased stand of ‘Merion’ Kentucky bluegrass in spring while disease symptoms were evident. In the initial study, sequentially applied (14-day interval) triadimefon (3.0 + 3.0) and terbuconazole (1.6 + 1.6) provided excellent control and commercially acceptable turfgrass quality 2 years after fungicide application. Propiconazole (1.7 + 1.7) provided good disease control; however, benomyl (6.1 + 6.1), fenarimol (3.0 + 3.0), iprodione (6.1 + 6.1), and prochloraz (7.6 + 7.6) provided poor disease control when plots were rated 2 years following application. In the second study, a single application of terbuconazole (1.6) and diniconazole (1.5 or 3.0) provided excellent stripe smut control, and turf exhibited commercially acceptable quality 2 years following fungicide application. Triadimefon-(1.5 or 3.0), terbuconazole- (0.8), and propiconazole- (1.7) treated turf exhibited reduced disease injury after 2 years; however, turf quality was not as good as that provided by the other fungicide treatments. Observations and data collected over 3 years do not support the view that U. striiformis-infected plants die during summer stress periods, thereby controlling the disease by reducing large populations of perennially infected plants. Chemical names used: methyl[1-[(butylamino)carbonyl]-1H-benzimidazol-2-yl]carbamate (benomyl); α-(2-chlorophenyl)-α-(-4-chlorophenyl)-5-pyrimidinemethanol (fenarimol); 1-isopropylcarbamoyl-3-(3,5-dichlorophenyl) hydantoin (iprodione); 1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(l,2,4,-triazol-1-yl)-1-peneten-3-ol (diniconazole is proposed); N-propyl-N-[2-(2,4-6-trichlorophenoxy)ehyl]-1H-imidazole-1-carboxamide (prochloraz); 1-(2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl methyl)-1H,2,4-triazole (propiconazole); a-[2-(4-chlorophenyl)ethyl]-a-(1,1-dimethylethyl)-H-l,2,4-triazole-1-ethanol (terbuconazole is proposed); 1-(4-chlorophenoxy)-3,3-dimethyl-1-(lH-l,2,4-triazol-1-yl)-2-butanone (triadimefon).

Open Access

Abstract

Seeds of Andropogon gerardii Vitman., Panicum virgatum L., Sporobolus heterolepis (A. Gray) A. Gray., Bouteloua gracilis (Willd. ex H.B.K.) Lag ex. Griffiths, Lotus corniculatus L. ‘Empire’, Bromus inermis Leyss., Trifolium hybridum L., Medicago sativa L. Subsp. Sativa ‘Vernal’, and Poa pratensis L. ‘Park’ were pregerminated and grown for 48 hours at 5°C increments between 12° and 37° and at 47°. No radicle growth occurred at 47° for any species. Maximum growth occurred at 27° for B. inermis and 32° for P. virgatum and A. gerardii. For other species, maximum growth occurred over a range of temperatures from 22° to 32°. P. pratensis and B. inermis, C-3 grasses, had no growth but B. gracilis, P. virgatum, and A. gerardii, C-4 grasses, had significant radicle growth at 37°C.

Open Access
Authors: and

Abstract

Eighteen cultivars representing 6 species (Poa pratensis L., Agrostis alba L., Agrostis palustris Huds., Agrostis tenuis Sibth., Festuca rubra Gaud., and Lolium perenne L.) of cool season turfgrass were exposed to 15 pphm ozone for 6 hours daily, 15 pphm sulfur dioxide continuously, 15 pphm nitrogen dioxide continuously, or a mixture of all three at these concentrations for 10 days. The most common symptoms of injury on sensitive cultivars in response to these gases were bleaching and necrosis of leaves with some cultivars exhibiting dark brown necrosis and stippling in response to O3 alone. Cultivars varied in sensitivity to O3 or SO2 from very sensitive to insensitive while few cultivars were sensitive to NO2 alone at the concentration used. Exposure of some cultivars resulted in less leaf area production but no visible injury symptoms, while other cultivars had leaf injury without reduction of area of uninjured leaves. The combined exposure caused more leaf injury and greater reduction in the leaf area production by most cultivars compared with plants exposed to single gases. Exposure to single pollutants could provide inaccurate estimates of turfgrass cultivar sensitivity outdoors where several pollutants may occur simultaneously.

Open Access

). Traditionally, the main turfgrasses grown in the transition zone are zoysiagrass ( Zoysia japonica Steud.), bermudagrass [ Cynodon dactylon (L.) Pers.], Kentucky bluegrass ( Poa pratensis L.), and tall fescue ( Festuca arundinacea Schreb.) ( Beard, 1973

Free access
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Abstract

The germination of grass seeds on freshly prepared lawns in the northeastern U.S. is usually enhanced by lightly mulching the shown seed with salt hay, (hay from salt marshes — a mixture of 2 grasses, Distichlis spicata and Spartina patens,) or cheesecloth to prevent the seeds from drying between rains or waterings. Salt hay is sometimes scarce and cheesecloth is expensive, so we evaluated other materials for this purpose.

Open Access