Turfgrass, Landscape and Urban IPM Research Report 1989
ABOUT THE COLLECTION
The Urban IPM and Turfgrass Research Summary Report is one of several commodity-based agricultural research reports published by the University of Arizona.
This report was first published in 1988.
The purpose of the report is to provide an annual research update to turfgrass managers, landscape professionals and IPM practitioners. The research is conducted by University of Arizona faculty and staff.
Both historical and current issues have been made available via the UA Campus Repository, as part of a collaboration between the College of Agriculture and Life Sciences and the University Libraries.
David Kopec and Paul Baker are current co-editors of the Urban IPM and Turfgrass Summary. You can email them at firstname.lastname@example.org. You can also visit the CALS Publications website for additional information.
Contents for Turfgrass, Landscape and Urban IPM Research Report 1989
- The Golf Industry in Arizona: An Economic Summary
- Performance Test - 1988 National Turfgrass Evaluation Program Bermudagrass Trials
- 1989 Tall Fescue Variety Trial
- Winter Turf Performance Trials
- Effects of Gypsum on a Wastewater Irrigated Turfgrass Soil
- Irrigation of Turfgrass with Secondary Municipal Sewage Effluent: Soil and Turf Aspects
- Turfgrass Evaluations of Curly Mequitegrass, Hilaria belangeri (Steud.) Nash.
- Germination of Lehman Lovegrass and Black Grama Under Controlled Environment Conditions
- Response of Purple Nutsedge to Repeat Application of Imazaquin Herbicide During 1988
- Assessment of Application Rate and Formulation of Imazaquin Herbicide on Purple Nutsedge Suppression
- Activity of Imazaquin for Purple Nutsedge Suppression Using Various Application Techniques
- Response of Overseeded Bermudagrass to Monsanto 15151 Herbicide
- Air-layering as a Method of Asexual Propagation of Mesquite
- Ethylene-Induced Flower Bud Abortion in Easter Lily is Inhibited by Silver Thiosulfate
- Characterization of Amino Acids and Carbohydrates Found in Whitefly Honeydew As the First Step Toward Bioloical Control
- Pregermination Treatments and Temperature Requirements for Germination of Mexican Redbud, Evergreen Sumac, and Mealy Sage Seeds
- Vegetative Propogation of Mexican Redbud, Larchleaf Goldenweed, Littleleaf Ash, and Evergreen Sumac by Stem Cuttings
- Relative Drought Resistance of Desert Willow, Fruitless Mulberry, and Yellow Bells
Relative Drought Resistance of Desert Willow, Fruitless Mulberry, and Yellow BellsDesert willow and yellow bells had a higher capacity to avoid drought than fruitless mulberry under moist conditions, but the reverse was true under dry conditions. Desert willow and yellow bells had a higher tolerance to dehydration than fruitless mulberry, resulting in a higher relative resistance to drought under either moist or dry conditions. Detached leaves from desert willow and yellow bells plants grown under stress restricted water loss better than those grown under no stress. Fruitless mulberry leaves lost water at essentially the same rate regardless of irrigation.
Vegetative Propogation of Mexican Redbud, Larchleaf Goldenweed, Littleleaf Ash, and Evergreen Sumac by Stem CuttingsEffect of cutting age (weeks after budbreak) and IBA concentration on percent rooting of Mexican redbud, larchleaf goldenweed, littleleaf ash, and evergreen sumac were investigated. Maximum predicted percent rooting was 88% for cuttings of Mexican redbud taken 4 weeks after budbreak and treated with 21 gliter⁻¹ IBA, 99% for cuttings of larchleaf goldenweed taken 6 weeks after budbreak and treated with 16 gliter⁻¹ IBA, 86% for cuttings of littleleaf ash taken 16 weeks after budbreak and treated with 17 gliter⁻¹ IBA, and 24% for cuttings of evergreen sumac taken 16 weeks after budbreak and treated with 5 gliter⁻¹ IBA.
Pregermination Treatments and Temperature Requirements for Germination of Mexican Redbud, Evergreen Sumac, and Mealy Sage SeedsScarification and stratification requirements of Mexican redbud and evergreen sumac seeds and the effects of temperature on Mexican redbud evergreen sumac, and mealy sage seed germination were investigated. The maximum predicted germination from a quadratic response surface was 94.9% after 62 minutes scarification and 35 days stratification for Mexican redbud and 59.3% after 52 minutes scarification and 73 days stratification for evergreen sumac. Mexican redbud seeds germinated from 23.8 to 30.5 C, evergreen sumac from 20.8 to 30.6 C, and mealy sage from 20.6 to 34.2 C. Maxium predicted final percent germination and the temperature at which it occurred for Mexican redbud, mealy sage, and evergreen sumac was 104.2 at 27.5 C, 89.8 at 29.2 C, and 42.4 at 22.1 C, respectively
Characterization of Amino Acids and Carbohydrates Found in Whitefly Honeydew As the First Step Toward Bioloical ControlA Florida strain of sweet potato whitefly, Bemisia tabaci (Gennadius), was found to have an expanded range which includes several new food crops. To determine why, we examined how it processes plant nutrients. The amino acid and carbohydrate content of phloem sap of poinsettia and pumpkin and of honeydew produced by the Florida strain and a strain from Arizona feeding on both plants were analyzed. Poinsettia phloem sap contained 15 amino acids; 14 of these were in pumpkin phloem sap. Almost all the same amino acids were in the honeydews produced by the two strains on the two hosts. Approximately half of the amino acids found in the honeydew were at concentrations which were significantly lower than concentrations in the phloem sap. Honeydew from both hosts contain six additional amino acids. The major one was glutamine which may be used to expel nitrogen. Carbohydrates in phloem sap and honeydew were common transport sugars, like sucrose. Both honeydews contained trehalulose, a disaccharide not previously associated with insects. Both strains processed phloem sap and honeydew from both plants in the same manner, but the Florida strain produced significantly larger quantities of honeydew; it is therefore assumed to process more phloem sap. Since this strain has access to more phloem sap it also has access to more of the amino acids which are in short supply in the phloem sap of some plants allowing it to broaden its range.
Ethylene-Induced Flower Bud Abortion in Easter Lily is Inhibited by Silver ThiosulfateFlower bud abortion, or "blasting" was shown to be at least partially caused by treating plants with ethephon, a chemical that releases ethylene. In floricultural greenhouses, ethylene could accumulate to levels that could induce commercially significant levels of flower bud injury. Silver thiosulfate (STS) was shown to be a potent inhibitor of ethephon injury. STS at (1 to 2 mM) could be applied as early as the visible bud stage (approximately 5 to 6 weeks before flowering) without phytotoxic effects. Using current silver prices, the material cost for our treatment is less than 0.4 cents per plant. Based on these results, a preventative STS application could potentially reduce much of the flower bud abortion seen in commercial greenhouses.
Air-layering as a Method of Asexual Propagation of MesquiteThree 12-year-old Prosopis chilensis were successfully layered in spring and late summer. The best rooting occurred with 1 cm stems treated with either 5,000 or 15,000 ppm IBA. Air-layers treated with IBA had a higher rooting rate and better root quality than untreated air-layers.
Response of Overseeded Bermudagrass to Monsanto 15151 HerbicideA one-time application of MON1S1S1 or 0.5 lb. ai /a on September 1, 1988, was evaluated for potential overseeding effects. Treated plots, which were overseeded with perennial ryegrass at 10, 20, or 30 lbs. per thousand square feet, were not significantly different compared to untreated plots for percent ryegrass stand and verdure. Only seed rate effects increased percent ryegrass and verdure weights slightly. These data show no detrimental effects of using MON15151 ("Dimension" trade name) six weeks before overseeding.
Activity of Imazaquin for Purple Nutsedge Suppression Using Various Application TechniquesAn experiment was devised to evaluate application technique, and elucidate the plant response (herbicidal activity) of imazaquin herbicide on single plants of purple nutsedge. Herbicide treated plants showed increased filleting and stunting 31 days after treatment. Soil treatments tended to increase herbicidal response. Imazaquin activity was minimized when the herbicide was not irrigated into the soil. Soil applied-imazaquin postponed the emergence of shoots from viable nutlets, but did not prevent emergence altogether.
Assessment of Application Rate and Formulation of Imazaquin Herbicide on Purple Nutsedge SuppressionA field test was implemented at Paradise Valley Country Club to investigate the effect of two rates of imazaquin (Image) herbicide (0.38 and 0.50 lbs ai /a) in both the granular (G) and emulsifiable concentrate formulation on purple nutsedge and common bermudagrass in a mixed stand (85 ± 20% nutsedge).
Response of Purple Nutsedge to Repeat Application of Imazaquin Herbicide During 1988Repeat sequential applications (1 - 4) of imazaquin herbicide were applied to 100% pure stands of purple nutsedge during the summer of 198& Treatments were applied every two weeks. Maximum suppression for plots receiving only one application was reached 1 month after application (25% control). Two 14-day sequential applications achieved 60% control 2 weeks after the second treatment. Both 3 and 4 sequential applications resulted in 88% and 92% control after 2 and 4 weeks from the third and fourth applications, respectively. Resprouting eventually reoccurred on all plots. This data shows the enhanced effect of repeat applications of imazaquin for purple nutsedge suppression.
Germination of Lehman Lovegrass and Black Grama Under Controlled Environment ConditionsMechanical scarification greatly improved the germination of Lehmann Lovegrass seed. Depending on the type and duration of scarification, seed gemzination can be improved from 10 %-12% germination (untreated seed) to over 90% (60-second scarification in a commercial seed scarifier). Black grama is sensitive to both dehulling and dehulling followed by scarification. Unhulled black grama seed should be used for field plantings.
Turfgrass Evaluations of Curly Mequitegrass, Hilaria belangeri (Steud.) Nash.Curly mesquitegrass, Hilaria belangeri, is being evaluated for utilization as a desert turf. Experiments were conducted on plant material collected throughout Arizona to: (a) quantify the natural variation in turfgrass qualities in this species; (b) evaluate the field performance of selected plant material to fertilizing and mowing practices; and (c) assess the effects of planting date and seeding rate on seedling establishment. Thirty-four percent of the rated plant material displayed low growing height while 26.9 % of the plant material had short leaf length. Thirty-five and 23.5 % of the rated plant material had acceptable or better than acceptable color ratings and fine leaf width, respectively. In another experiment, nitrogen had no significant effect on plant color, however, increasing nitrogen increased percent ground cover. Percent ground cover also increased as the height of cut increased. Substantial variation was observed in the number of stolons per plant, and high stolon numbers were not associated with high nitrogen levels. Planting time had a significant influence on seedling establishment. Seeding rates also differed significantly in the number of seedlings established per m².
Irrigation of Turfgrass with Secondary Municipal Sewage Effluent: Soil and Turf AspectsThis field experiment evaluated the use of secondary municipal sewage effluent for irrigation of two turfgrass species. In April 1987 common bermudagrass (Cynodon dactylon L. Pers.) was seeded to a gravelly sandy loans soil and maintained under fairway conditions. Perennial ryegrass (Loliman perenne L.) was overseeded in the fall to maintain an actively growing turf. Plots were irrigated identically with either effluent or potable water. Soil and irrigation water samples were collected periodically and analyzed for pH, electrical conductivity (EC), sodium (Na), calcium + magnesium (Ca +Mg), bicarbonates (HCO₃), nitrogen (N), phosphorus (P) and potassium (K). Effluent water was found to contain a higher sodium absorption ratio (SAR), EC and greater concentrations of all the above elements with the exception of pH. Effluent irrigation lead to significantly lower seed germination and resulted in higher EC, Na, nitrate- nitrogen (NO₃-N), P and K concentrations in soils. Turf quality was assessed by visual evaluation under four N fertilization rates in each irrigation regime. Established effluent irrigated turf did not show signs of osmotic stress with a 15-20% leaching fraction and responded to the nutrient content of this water during periods of higher irrigation rates. However, no single fertilization rate or irrigation regime consistently produced a superior turf quality. Secondary municipal sewage effluent was used successfully for turf irrigation but the greater EC, Na and nutrient content of the water need to be considered by the turf professional making management decisions.
Effects of Gypsum on a Wastewater Irrigated Turfgrass SoilSecondarily treated wastewater is used extensively in the southwestern United States for turfgrass irrigation, but deterioration in soil quality can occur from sodium (Na) delivered by this water. Application of gypsum (CaSO₄2H₂O) at 2 240 kg ha⁻¹ yr⁻¹ is often recommended to control the Na. Research to determine if this rate is effective on effluent -irrigated turfgrass sites is lacking. A 2-yr study was carried out on a golf course fairway (typic tomf7uvent soil) with a 10 yr history of effluent irrigation and elevated Na levels (800 mg kg⁻¹). Four rates of gypsum (0, 2 240, 4 480, and 8 960 kg ha⁻¹) were surface applied in November 1986 and 1987. Soil samples were collected every 3 months after treatment (MAT) and analyzed for Ca (total and water - soluble (WSCa)), Mg, K, Na, SO₄⁻²-S (S), pH, and electrical conductivity (EC). Results showed elevated WSCa and S levels 3 and 6 MAT in both years. The two highest rates resulted in elevated S levels 12 MAT. During both years, gypsum at the two higher rates decreased Na levels within 3 MAT. The lowest application rate did not reduce Na levels until 12 MAT in 1987 and its effects were not as great. Following the second annual application, the 2 240 kg ha⁻¹ rate was as effective as the higher rates in reducing Na levels 6 and 12 MAT. Total Ca levels were not affected by gypsum but Mg and K levels did decrease. In both years, a temporary increase in EC and decrease in pH occurred after gypsum treatment. It appears that gypsum at 2 240 kg ha⁻¹yr⁻¹ can be as effective as higher application rates in reducing Na in effluent-irrigated turf soil but only after two applications.
Winter Turf Performance TrialsOverseeding trials were conducted to evaluate the turf-type fitness of cool season grasses for use in the desert when bermudagrass is dormant. Perennial ryegrass, fine fescues, rough stalk bluegrasses and creeping bentgrasses were tested for turfgrass quality, color, percent ground cover and uniformity under a close mowing (3/8 inch) regime. Entries varied significantly from each other once seasonal hard frosts did not recur after January. Certain entries had better turf performance under hot (late spring) conditions. Both commercially available and experimental germplasm were evaluated.
1989 Tall Fescue Variety TrialTall fescue is a very heat and drought tolerant, cool season turf, which can remain green throughout the year in the arid Southwest. Data are lacking on the performance of tall fescue varieties in this location. Sixty-five tall fescue entries were established in November 1987 and their performance as a home-lawn turf rated for quality, color, density, percent ground cover, pest incidence and water use. All varieties performed very well during the first seven months of 1989, but a decline in August quality was observed during summer monsoons mainly due to the incidence of large brown patch (Rhizoctonia solani L.) and record-setting high temperatures. Turf still showed signs of stress by mid-September. Turfgrass irrigation water use from 1 January to 23 September totalled 43.3 inches (1100.5 mm) and averaged 63 % of predicted evapotranspiration.
Performance Test - 1988 National Turfgrass Evaluation Program Bermudagrass TrialsBermudagrass germplasm was evaluated for turfgrass color, quality, chlorosis symptoms, leaf texture and percent plot ground cover, in order to assess turf adaptation under desert conditions. Both experimental materials and commercially available germplasm were different for these traits during 1988, which was the second year's evaluation of a 5-year-long national trial for turf-type bermudagrass.
The Golf Industry in Arizona: An Economic SummaryIn 1987, 191 golf facilities in Arizona were surveyed to determine the employment, income, revenues, and expenditures generated by the state's golf course industry. The direct plus indirect employment and income benefits are estimated to be 12,400 jobs and $155 million in wages, respectively.