Number Of Grubs Research Articles

European Chafer on Turf, Jackson Co., Mi, 1995

Abstract An area of non-irrigated rough at The Country Club of Jackson in Jackson County, MI was used for this test. Plots were 3 ft X 3 ft separated by a 2 ft wide buffer strip. All treatments were replicated 5 times. Treatments 1, 2, 3 and 19 were applied on 22 May. Treatments 1, 2 and 3 were immediately irrigated by hand with Vi ½ inch water. 0.8 inches of rain fell over the next 2 days. Treatments 4, 5, 6 and 21 were applied on 12 Jul under extremely warm and dry conditions. Treatments 4, 5 and 6 were irrigated by hand with Vi ½ inches of water immediately after application. All curative treatments were applied on 20 Aug between 10:00 and 3:00 in sunny, warm (85°F) and very dry conditions with slight 0-3 mph winds. Treatments 7, 8 and 9 were immediately irrigated by hand with V4 °inch water. No rainfall fell on the plots until 16 Sept. All applications were made with a hand-held CO2 R&D Sprayer with a single 8003 nozzle at 38 psi at a rate of 175 gal/A finished spray. The plots were evaluated on 30 Sep by digging a 2 ft2 area from the middle of each plot and counting the number of grubs.

Green June Beetle Control on Golf Course Fairways in North Carolina 1995

Abstract Two formulations of Bacillus thuringiensis japonesis Buibui were evaluated for control of GJB grubs on a bermudagrass fairway at the Quail Ridge Golf and Country Club in Sanford Turfgrass on the site is mowed at 0.88 inch and has 0.25 inch of thatch. The sandy loam soil had a pH of 5.6 and 0.51% humic matter. Plots 10 ft X 10 ft were established in an area with a history of GJB infestation and treatments (replicated 4 times) were randomly assigned to the plots. Insecticides were applied on 14 Aug under sunny skies (95°F) to a population of primarily 1st and 2nd instar grubs. The spray formulations were applied using a CO2-powered backpack sprayer with 8003 nozzles delivering approximately 30 gpa and operating at 40 psi. The area received 0.5 inch of irrigation the night before treatment and 0.25 inch of irrigation following treatment. All plots were oversprayed on 5 Sep with a 4.8 lb Al/acre rate of Sevin 80 WPS and were evaluated on 6 Sep (23 DAT) by counting all the dead grubs on the surface within two randomly placed one m2 frames in each plot. The dead grubs from the Sevin overspray are assumed to have survied the initial “test” treatments. The average number of grubs counted (per m2) in each plot are reported in the table. All data were transformed x + 0.5 prior to ANOVA and DNMRT.

Importance of Treatment Duration for Praziquantel Used against Larval Digenetic Trematodes in Sunshine Bass

The effectiveness of praziquantel (Droncit) against yellow grubs Clinostomum complanatum and unidentified, encysted, larval trematodes was tested in infected sunshine bass Morone chrysops female × M. saxatilis male. Praziquantel treatments significantly reduced the total number of live grubs in the fish in most treatment regimes tested. Treatment at 0.25 mg/L for 24 h was as effective as one at 8 mg/L for 8 h. Mature dead and dying metacercaria may have released toxins that killed host fish in some treatments.

Control of White Grubs at the Purdue University Agronomy Research Center, W. Lafayette, In, 1994

Abstract Treatment plots were 2 × 2 ft, arranged in a RCB design, replicated 5 times. A PVC cylinder (6 inch inside diameter) was buried 4 inches into the soil and projected 1 inch above the soil in the center of each plot. Five third-instar grubs (mixed population consisting of about 90% Japanese beetles and 10% Southern masked chafers) were infested within each cylinder 5 d prior to treatment, 2 Sep. Granular formulations were applied with a homemade salt shaker. All plots received 0.5 inches of irrigation immediately after treatment. Conditions at the time of treatment were: air temp., 21°C; soil temp, at 1 inch, 20°C; thatch depth (natural), 0.13-0.25 inches; soil texture, silt loam; wind speed 3-5 mph. Efficacy was evaluated 30 DAT by extracting the cylinders, separating the soil and grass, and recording the number of live grubs.

Control of the Southern Masked Chafer at the Purdue University Agronomy Research Center, W. Lafayette, In, 1993

Abstract All treatments were applied to a 4 ft2 area (plot), replicated five times in a RCB design. A PVC cylinder (6 inch inside diam) was buried 4 inches into the soil and projected 1 inch above the soil in the center of each plot. Five third-instar grubs were infested within each cylinder, with the exception of plots treated with Merit which were infested with second-instar grubs, 2 d prior to treatment, 2 Sep. Dispersible formulations were applied at 2 gal/1000 ft2 using a 2 pint squeeze bottle with a mist nozzle. Granular formulations were applied with a homemade salt shaker. All plots with the exception of those treated with Triumph, Diazinon, and one Orthene 15G treatment (not watered-in), received 0.5 inches of irrigation immediately after treatment. Triumph and Diazinon treatments were irrigated with 0.5 inches of water 24 h after treatment. Conditions at the time of treatment were: air temp., 22°C; soil temp, at 1 inch, 20°C; thatch depth (natural), 0.13-0.25 inches; soil texture, silt loam; RH 92%; wind speed 3-5 mph. Turf in PVC cylinders that was treated with chlorpyrifos (FN 5354 and NAF-53) and its associated wetting agent (HM 8902) was brought in from another location and had a thatch layer of 0.5 inches. Efficacy was evaluated 30 DAT by extracting the cylinders, separating the soil and grass, and recording the number of live grubs.

Efficacy of Entomopathogenic Nematodes Against Japanese Beetle Grubs, 1992

Abstract The experiment was conducted on a golf course fairway rough in Amherst, NH. The experimental design was a RCB, replicated 4 times with 8 ft × 8 ft plots. Treatments were applied 3 Sep and rated 24 Sep. At the time of application, JB were predominantly 2nd instar. Nematodes and Triumph were applied with a watering can in 5 gal/1000 ft2 at 1700 h. Nematodes were checked for viability before application. Treatments were not watered in because it was unnecessary due to the high soil moisture and rain. The plots were irrigated as necessary throughout the trial period to maintain good soil moisture. These plots hadn’t received any other insecticides for at least 1 year previously. Plots were rated by counting the number of live grubs per 2.25 ft2 of turf. Conditions at the time of treatment were: air temperature, 55.4°F, 1 inch depth 62°F, 2 inch depth 62.7°F; soil pH, 5.8: slope, 0% soil texture, loam, 43% sand, 47% silt, 10% clay; soil organic matter, 6.8%; soil moisture, 24.8%; precipitation, drizzle for 8 h pretreatment and 14 h posttreatment.

Efficacy of Entomopathogenic Nematodes Against the Japanese Beetle Grub on a Golf Course Fairway, 1993

Abstract Three formulations of nematodes were tested against Japanese beetle grubs at the Amherst Country Club, Amherst, NH. Treatments were applied to 2nd instar grubs on Sep 2 from 1800 to 2100 h. Plot size was 8 × 8 ft with a 3 ft buffer between plots. Plots were arranged in a RCB design with 4 replicates. All treatments were applied in a watering can. All treatments were applied in water at a volume of 5 gal/1000 ft2. Immediately after application, plots were irrigated with 0.5 inch water and kept irrigated as necessary to keep the soil moist. Conditions at the time of treatment were: soil pH, 5.9; water pH, 6.8; soil texture, loam, 40% sand, 40% silt, 20% clay; soil moisture, 19.7%; OM, 5.1%; soil temperature at 1 inch 77.2°F, soil thatch, 0.5 inch; sky, cloudy. Plots were rated on Sep 30 by counting the number of live grubs under a 3 ft2 section of sod cut by a sod cutter.

Control of Billbug Larvae and a Subsequent White Grub Population on a Lawn Area in Wayne County, Ohio, 1993

Abstract The study was located lawns of the Agricultural Technical Institute at Wooster, Ohio. Insecticides were applied 15 Jun to plots 10 x 10 ft arranged in a randomized complete block, replicated 4 times. Granular insecticides were applied using a drop spreader and liquids using a CO2 sprayer with Teejet 8010LP nozzles at 30 psi that delivered a volume of 3 gal/1000 ft2. The experimental area received no posttreatment irrigation. Environmental conditions at time of treatment were as follows. Billbugs: early instars present, no pretreatment count. Turf: 3° slope, dry, 3 in height, 50% Kentucky bluegrass, 50% perennial ryegrass. Thatch: moist, Vi inch, dense. Soil: moist, 68°F at 1 inch and 55°F at 3 inches. Weather: sunny, 73°F, 5-8 mph. Water: pH 4.9. Billbug efficacy data taken from each plot 9 Jul (28 DAT) were based on the number of live billbug larvae and pupae in 6, AVi inches in diam samples from each plot. Efficacy data for control of a subsequent JB and NMC larval population (appx 70% JB: 30% NMC) taken 5 & 7 Oct was based on the number of live grubs in 6, 7 × 7 in samples from each plot.

Full Season Japanese Beetle Grub Control with Merit, 1993

Abstract Two formulations of Merit were compared for efficacy against Japanese beetle grubs on a golf course fairway in Amherst, NH. Plots were 10 × 10 ft, replicated 4 times in an RCB design. Treatments were applied 26 Apr and rated 24 Sep. The granular formulation was applied with a homemade salt shaker. The wettable powder was applied in a watering can at a volume of 5 gal water/1000 ft2. After application, plots were irrigated with 0.5 inches water. Plots were rated by counting the number of live grubs in a 3 ft2 sample. Conditions at the time of treatment were: air temperature, 53.3°F; soil temperature, 2 inches, 50.8°F; thatch depth, 0.5 inch; soil pH, 5.8; slope, 1%; soil texture, sandy loam, 53% sand, 43% silt, 4% clay; soil organic matter, 6.5% soil moisture, 19.4%.

Spring Management of White Grubs in Chesterfield, In, 1993

Abstract Treatment plots were 6 ft × 2 ft, arranged in a RCB design, replicated 5 times. Treatments were applied 7 May. Triumph and Dursban were applied with a COypressurized backpack sprayer using 11003 nozzles, operating at 20 psi and delivering 20 gal/acre. Granular formulations were applied using a homemade salt shaker. All plots were irrigated with 0.25 inches of water immediately after treatment. Conditions at the time of treatment were: air temp., 27°C; thatch depth (natural), 0.5-0.75 inches; soil texture, silt loam; soil pH 5.6; wind speed 2-8 mph. Efficacy was evaluated 21 May using a sod cutter that excised the turf to a depth of 0.75 inches. The sod (6 ft × 1.5 ft) cut by the sod cutter was turned over and the number of grubs clinging to the grass roots and exposed on the ground was recorded.

Fall Control of Japanese Beetle Grubs with Conventional and Experimental Formulations on Turfgrass in Wayne Pa, 1993

Abstract The turfgrass area consisted primarily of annual bluegrass (50%) and creeping bentgrass (50%). Treatment plots were 9 × 6 ft, arranged in a RCB design and replicated 3 times. Granular formulations were applied with a hand-held shaker and mixed with a fine grade top-dressing sand to facilitate product distribution. Liquid formulations were applied with a CO2 compressed air sprayer with 4 8004VS TeeJet nozzles mounted on a 6 ft boom, operating at 28 psi, and delivering 5 gal/1000 ft2. At treatment time (23 Aug) the following soil and environmental conditions existed: air temperature, 66°F; soil temperature at 1 inch depth, 70°F; soil temperature at 2 inch, 69°F; RH, 85%; amount of thatch, 0.125 inches; soil type, loam; soil particle size analysis: 37.0% sand, 45.0% silt, 18.0% clay; organic matter, 5.0%; soil moisture (oven baked), 31.6; water pH, 7.0; soil pH, 5.1; and overcast skies. Immediately after treatment the experimental area was irrigated with 0.5 inches of water. Posttreatment counts were made 49 DAT (11 Oct). Japanese beetle grub control was evaluated by removing four 0.087 ft2 sod samples from each replicate, and the total number of grubs were recorded and converted to a ft2 count. Sod samples were removed with a 4 inch diam cup cutter.

Persistence of dryland pasture species in mixed swards in Canterbury

Changes in dryland pasture composition were monitored over 5 years in pastures that were managed under a normal sheep farm management system. Grass grub population built up with time and appeared to be the main reason for plant loss and the resultant changes in pasture composition. Grass grub densities in ryegrass mixtures increased to a high level (220/m* ) by year three, with subsequent ioss of ryegrass plants. Grub densities increased more slowly in cocksfoot-, tall fescueand phalaris-based pastures, with no apparent loss of plants. Cocksfoot dominated pasture composition by year three, even when sown at only 25% of total seed mix. Phalaris did not increase its contribution and at no stage made a significant contribution to production when sown in mixtures with other grasses. As grass grub numbers declined there appeared to be some regeneration of the ryegrass component. The more persistent cocksfoot and tall fescue pastures increased their herbage yield advantage over ryegrass pastures with time. Autumn animal performance was directly related to the amount of green herbage on offer. Keywords: Costelytra zealandica, Dactylis glomerata,dryland pastures, Festuca arundinacea, Lolium perenne, Phalaris aquatica, pasture composition

Evaluation of Granular Formulations of Insecticides for Control of Japanese Beetle and Northern Masked Chafer Grubs on a Golf Course Rough in Franklin County, Ohio, 1991

Abstract Experimental plots consisting of approximately 80% Kentucky bluegrass and 20% perennial ryegrass were established and treated on 29 Jul. Treatment plots were 3.05 m squares, separated by 0.9 m alleys, arranged in a randomized complete block design and replicated 4 times. Liquid treatments were applied using a C02 sprayer (40 psi with four 8015 Teejet nozzles) calibrated to deliver 0.16 liter/m2, and granular products were applied using a 0.61 m Gandy Turf Tender drop spreader. The entire experimental area was irrigated with 6.35 mm water (7.96 pH) immediately after treatments were applied. At treatment time, conditions were: sky cloudy, air temperature 24.4°C, wind 0-19 km/h, soil temperature at 2.5 cm = 26.7°C and at 7.6 cm = 25.0°C, and the turf had a dense thatch 6.35-12.7 mm thick, with mowing height 4.4 cm. Posttreatment counts were made 58 d later (25 Sep) by taking six 17.8 × 17.8 cm (= 0.03 m2) samples randomly from each treatment plot and recording the number and species of grubs.

Field Efficacy and Persistence of Entomogenous Nematodes in the Management of White Grubs (Coleoptera: Scarabaeidae) in Turf and Pasture

The entomogenous nematodes Steinernema carpocapsae (Weiser) and Heterorhabditis Heliothidis (Khan, Brooks &; Hirschmann) were used to control white grubs in turf and pasture. In the turf trial, nematode concentrations of 0.25, 0.5, or 1 million nematodes per m2 were evaluated. Only 12% of the grubs were killed by the nematodes at all three concentrations. In the pasture trial, nematode concentrations of 0.5 and 1.5 million per m2 were applied alone or in combination with diazinon (2.25 kg [AIl/ha). Comparisons (t tests) of the mean number of grubs recovered from each treatment area 2-4 wk after application showed significant reductions in the grub populations in both trials after certain nematode treatments. When applied at a rate of 1.5 million per m2, nematodes persisted for 8 wk after application in the pasture trial. In other tests of persistence, nematodes survived as long as 5 wk after application. Nematophagous fungi were recovered from treated areas and untreated plots; however, no significant increases in numbers of propagules occurred after application. Predaceous mite populations did significantly increase after application in one trial. Many of these mites are considered nematophagous.

A model for estimating abundance of cattle grub (Diptera: Oestridae) from the proportion of uninfested cattle as determined by serology*

A model is presented for determining the abundance of cattle grubs in the backs of calves from the proportion of uninfested calves in a herd. The distribution of grubs in calves' backs was compared with the negative binomial, but no relationships were found among the distribution parameters, suggesting that the negative binomial is an inappropriate choice for the basis of a sampling model. The relationship between the mean number of grubs per animal (mean), variance (delta 2), and proportion of uninfested calves (p0) in a herd was determined and used as the basis for the sampling model. The relationship between p0 and p0e [determined using serology (ELISA)] was evaluated. The variance of estimates of mean grubs per animal based on the regression model and uncertainty due to using p0e as an estimate of p0 was examined. A test of the model indicated that p0e could be used to obtain a reliable estimate of mean grubs per animal and that the method would be applicable for monitoring grub populations, assessing chemical control programmes, and determining release rates of sterile insects for control.

Effect of Droncit (Praziquantel) on Yellow GrubsClinostomum marginatumand Eye FlukesDiplostomum spathaceumin Channel Catfish

Abstract Channel catfish Ictalurus punctatus with infections of yellow grubs Clinostomum marginatum and eye flukes Diplostomum spathaceum were treated with 2 mg Droncit (praziquantel)/L in a water bath for 2 and 4 h. At the time of treatment, 80% of the fish had visible yellow grubs and 70% had opaque eyes. Fourteen days after treatment, 40.1% of the yellow grubs in the 2-h treatment were dead. No grubs were dead in the 4-h treatment; however, the number of yellow grubs was reduced in the treated fish. No dead eye flukes were seen in untreated fish after 14 d, but 59.2 and 44.4% of eye flukes in the 2- and 4-h treatments, respectively, were dead. At 21 d, the percentages of dead eye flukes were 86% (2 h) and 90.1% (4 h). Droncit had limited effect on yellow grubs in channel catfish, but the chemical had a beneficial effect of reducing numbers of eye flukes.

Early detection of cattle grub (Hypoderma lineatum and H.bovis) (Diptera, Oestridae) using ELISA

An enzyme-linked immunosorbent assay (ELISA) to detect cattle grub-infested animals in the autumn in Alberta has been developed. Antibody to Hypoderma lineatum de Vill. was detectable as early as 6 weeks post-infestation in artificially infested steers. Peak antibody concentrations preceded the peak in maximum 'apparent' grub numbers which occurred between 37 and 43 weeks after infestation. Natural infestations with H. lineatum and H. bovis L., ranging from one to ninety-two grubs per calf, were readily detected by November and the incidence of false positives in uninfested calves was only 5%. Low level (1-4 grubs) infestations of H. bovis only became detectable in February with peak antibody concentrations occurring at the end of April. Prevalence of cattle grub infestations in southern Alberta was shown to be 37% during this study.

Biological control of grass grub in Canterbury

The grass grub (Costelytra zealandica) is a major pest of Canterbury pastures. Grass grub numbers are low in young pastures and then commonly rise to a peak 4-6 years from sowing, before declining. Grass grub numbers in older pastures fluctuate but rarely reach the same levels as the early peak. Biological control agents such as bird and invertebrate predators, parasites and diseases cause mortality in grass grub populations; the effect of predators and parasites is limited. Pathogens are common in grass grub populations. Amber disease, caused by the bacteria Serratia spp., was the disease most frequently found in population surveys in Canterbury, while milky disease (Bacillus popilliae) and protozoan diseases were less common. The level of amber disease was reduced in pastures where insecticide had been applied. Inundative applications of entomophagous nematodes and the bacterium Serratia entomophila have been tested against grass grub. A bacterial productbased on S. entomophila is now being marketed for grass grub control. Keywords grass grub, biological control, pathogens

Grass grub tolerant pastures and fertiliser nitrogen as an alternative to white clover in pasture subject to grass grub attack

The effect of replacing white clover with fertiliser nitrogen (N) on dry matter production and grass grub populations in 'Grasslands Roa' tell fescue (Festuca arundinacea Schreb.), 'Grasslands Mat-u' phalaris (Phalutis aquatica L.), 'Grasslands Kara' cocksfoot (Dactylis glomerata L.), 'Grasslands Mama' prairie grass (Bromus willdenowii Kunth) and 'old' (30 year plus) ryegrass was measured over a 2 year period. For all pastures the replacement of white clover with fertiliser N significantly reduced grass grub numbers. This was greatest in tall fescue, phalaris and cocksfoot, showing that pure swards of these species were resistant to grass grub. Decreases in grass grub numbers in ryegrass and prairie grass were less. There was overall a significant increase in pasture production by eliminating white clover and applying fertiliser N, with a differential response between species. Average annual production of prairie grass was unaffected, whereas the yield of cocksfoot increased by 9 % and old ryegrass, phalaris and tall fescue increased by 26 % . Most of this extra production for tall fescue and phalaris occurred in autumn. These results show that the use of tall fescue and phalaris and the replacement of white clover with fertiliser N has potential for increasing pasture production in districts subject to grass damage. Keywords old ryegrass, Roa tall fescue, Maru phalaris, Kara cocksfoot, Matua prairie grass, white clover, grass grub, nitrogen fertiliser

Mortality of Ligyrus subtropicus (Coleoptera: Scarabaeidae) by Entomogenous Nematodes in Field and Laboratory Trials

Studies on control of Ligyrus subtropicus (Blatchley) by two entomogenous nematodes showed that field releases of Steinernema feltia Filipjev (Strain All) did not cause a significant reduction in the number of L. subtropicus grubs in sugarcane, Saccharum spp. Field releases of S. glaseri (Steiner) also failed to significantly reduce the number of grubs, but S. glaseri appeared to be more effective than S. feltia . Differences in the mean percentage of dead grubs per 0.61 m of row (16.6% for S. glaseri and 2.7% for S. feltia ) were detected between plots treated with S. glaseri and control plots 6 wk after treatment. Differences in total percentage of grub mortality between plots treated with S. glaseri (50.57%) and control plots (11.13%) 8 wk after the release of S. glaseri also were significant. Bioassays exposing Galleria mellonella (L.) larvae to nematodes from dead grubs collected in plots treated with S. glaseri resulted in significantly higher mortality of G. mellonella in the treated group than in the control group. In laboratory tests, mortality of pupae and adults was 100 and 42%, respectively, when each was treated with 5,000 S. glaseri nematodes.