Central Research Station Research Articles

(27) Effect of Plant Stand Density and Pesticide Application Technology on Insect Pests and Diseases of Bell Peppers

The impact of pesticide application technology and crop stand density on bell pepper production was evaluated in a series of field trials, during 2004 and 2005, at the North Central Agricultural Research Station, Fremont, Ohio. In 2004, one trial tested three sprayers, at a speed of 8 and 4 mph, using insecticides at half the recommended rate and one treatment at full rate. Sprayers evaluated included an air-assisted electrostatic sprayer, a Cagle sprayer equipped with AI-11005 or AI-110025 nozzles, and an air-blast sprayer with XR-1003-VS or XR-110015-VS nozzles. In 2005, one experiment tested the interaction of two application technologies, three planting distances within row, and single vs. twin rows. Another experiment compared the Cagle sprayer (with TJ60-11003 or AI-110025 nozzles) and the airblast sprayer (with XR-110015-VS nozzles), at a speed of 4 mph, and insecticides at half the recommended rate. In 2004, the Cagle sprayer with air-induction nozzle, half rate, at 8 mph obtained the highest fruit yield. There was not significant improvement in European corn borer control by applying insecticides at full rate with the Cagle sprayer and all treatments achieved significantly better bacterial soft rot control than the untreated control. In 2005, the trials were terminated early due to crop destruction by Phytophthora capsici. Red fruit weighed less at high than at medium or low plant stand densities. Clean yield of red fruit was significantly greater in single rows than in twin rows. Marketable yield of green fruit was greater using the TJ60-11003 than using the AI-110025 nozzles.

Invasive Species as Ecological Threat: Is Restoration an Alternative to Fear-based Resource Management?

Invasive species is a hot topic in the USDA Forest Service these days. Along with wildfire, land conversion and unmanaged recreation, Chief Dale Bosworth has called invasive species one of the `Four Threats` needing the attention of Forest Service land managers and researchers (USDA Forest Service 2004). My unit of the Forest Service, the North Central Research Station, has responded to the call by focusing a portion of our research capacity on invasives. As a social scientist, I began looking for my niche in the issue by searching the literature for what had been done on the social aspects of invasive species.

Determination of Surface Drainage Coefficient Through Rainfall Analysis

The drainage coefficient for agricultural watershed at Central Research Station of PDKV Akola (CRS) was estimated. For this purpose 25 years daily rainfall data was used for its depth- duration- frequency analysis to get one to four consecutive days rainfall values for 2, 5, 10 and 20 years recurrence interval (R.I.) Computed drainage coefficients (DC) indicates that the soils at CRS having basic infiltration rate above 3, 5, 7 and 8 rom/hour may not need surface drainage system for one day period rainfall of 2, 5, 10 and 20 years R.I. respectively. The corresponding values in case of two consecutive days rainfall are 2, 3, 3 and 4 mm/hr. For three consecutive days rainfall these values are I, 2, 2 and 3 rom/hr respectively and for four consecutive days rainfall values are 1,1,2 and 2 rom/hr. In case of one day period the estimated drainage coefficient varies between 64.14 rom/day to 112.14 rom/day for 5 years RI. And between 102.06 to 150.06 rom/day for 10 years RI. in clayey soils at CRS having basic infiltration rate 1 to 3 rom/hr. However, in case of two consecutive days maximum rainfall the estimated values of drainage coefficient (DC) varies between 7.81 to 55.81 rom/day for 5 years R.I. and 22.58 to 70.58 rom/day for 10 years RI. having same type of black cotton soil. In case of three consecutive days maximum rainfall the corresponding values of DC are 8.55 to 32.55 rom/day for 5 years R.I. and 17.11 to 41.11 rom/day for 10 years RI. having basic infiltration rate 1 to 2 rom/hr. Study further revels that soils at CRS having predominantly clayey soils with basic infiltration rate between I to 3 rom/hr may necessarily have to be provided with agricultural land drainage for its major existing crops

STUDIES ON PERFORMANCE OF HORIZONTAL POWER INTAKES

ABSTRACT Intakes structures are commonly used for withdrawing water from river, reservoir and conveyance system of hydropower projects or for pumping stations. Formation of air-entraining vortices in front of intake is the result of complex interaction between many parameters and cause operational problems for turbine or pump and reduction of coefficient of discharge. Therefore, submergence provided at the intakes should be adequate to avoid air-entraining vortices. The submergence provided in horizontal intakes of Nathpa Jhakri, Chamera and Tala hydroelectric power projects were studied by way of hydraulic models at the Central Water and Power Research Station, Pune. The criteria for safe submergence without air-entrainment suggested by various researchers were compared with the actual submergence provided in all the three projects. Few guidelines provided in the literature were fitting well with the model results whereas other guidelines including one, which is suggested by IAHR manual, appeared to be highly conservative.

Effect of plantinggeometry and nitrogen on yield, economics and nitrogen uptake of sweet corn (Zea mays)

A field experiment was conducted during rainy seasons of 2002 and 2003 at Central Research Station, OUAT, Bhubaneshwar to study the effect of planting geometry and nitrogen on sweet corn (Zea mays L.) cv 'Madhuri'. Twenty treatment combinations, comprising four spacings (45 cm x 30 cm, 45 cm x 20 cm, 60 cm x 30 cm and 60 cm x 20 cm) allotted to the main plots and five nitrogen levels (0, 20, 40, 60 and 80 kglha) to the sub- plots, were tested in split-plot design with three replications. The spacing of 60 cm x 20 cm significantly in- creased the number of prime cobs (54,108/ha), green-cob yield (9.21 t o ~ e d h a ) , nitrogen uptake (53.62 kglha), protein yield (174.35 kglha) and accrued highest net return (Rs 48,5711ha) and benefit : cost ratio (3.55), fol- lowed by 45 cm x 30 crn spacing. Application of 80 kg Nlha produced significantly highest number of prime cobs (62,328/ha), green-cob yield (9.80 tonneslha), length (17.5 cm) and girth (16.7 cm) of cobs, green-forage yield (17.35 tlha), total N uptake (91.2 kglha) and protein yield (280.8 kglha). Significantly highest net returns (Rs 61,5321ha) and benefit : cost ratio (3.76) were realized with 80 kg Nlha, followed by 60 and 40 kg Nlha.

Effect of zinc and nitrogen fertilization on summer rice (Oryzasativa)

Zinc deficiency appears to be the most texture, slightly acidic in reaction (pH 6.5), important nutritional factor limiting growth medium in available N (322 kgha), availa- and yield of wetland rice (Oryza sativa L.) ble P (Olsens P 14.5 kglha) and available K next to nitrogen and phosphorus. It is a (1 56 kg/ha). major component and activator of several Sarathi (1 15 days) rice was transplant- enzymes and involved in metabolic ed on 25 and 15 February during 1991 and activities, viz. auxin metabolism, protein 1992 respectively at 15 cm x 1a0 cm spacing. synthesis, nucleic acid and carbohydrate The maximum mean grain and straw metabolism, and utilization of nitrogen and yields of 45.8 and 62.1 qlha respectively . phosphorus. Krishnamurthy (1979) reported were obtained at the highest level of nitro- synergistic effect between applied nitrogen gen. The increase over 0,30 and 60 kg N/ha and zinc in rice. was 49.8, 20.7 and 7.3% for grain and 56.1, Hence an investigation was camed out to 25.2 and 10.1 % for straw yield respectively. study the effect of zinc and nitrogen Application of zinc increased the grain fertilization on grain and straw ,yields of and straw yields significantly over no zinc summer rice. application, which might be owing to better A field experiment was conducted at the utilization of N and P for grain production Central Research Station, OUAT, Bhu- through greater metabolic activities. Com- baneshwar, during summerseason of 1991 bined application of N and Zn increased the and 1992. The treatments consisting of 2 grain and straw yields by 7.2 and 12.9% re- --- sources of zinc (S1, ZnS0, and S,, Zn- spectively over alone application of N. The EDTA), 2 methods of application (MI, soil increase in both grain and straw yields was and M,, foliar application) supplemented owing to their synergistic effect. Similar re- with 4 levels of nitrogen (0, 30, 60 and 90 sults were obtained by Vyas et al. (1990) in kglha). The treatments were tried in rand- irrigated rice. omized block design with 3 replications. The sources and methods of application Zinc sulphate (22% Zn) @ 25 kg/ha and Zn- of Zn influenced the yield significantly in EDTA (12% Zn) @ 500 g/ha along with 10 both the seasons. Among the sources, kg carder were applied basal. Foliar sprays ZnSO, increased the grain and straw yields of ZnSO, at 0.4% and Zn-EDTA at 0.05% by 2.5 and 4.2% respectively over Zn- - concentration were given at 25 and 35 days EDTA, which was due to optimal supply of 1 after transplanting. Zn from ZnS0, as well as, beneficial effect The experimental soil was sandy loam in of sulphur present in it.

Diameter Growth Models Using Minnesota Forest Inventory and Analysis Data

Abstract The Forest Inventory and Analysis (FIA) program of the USDA Forest Service North Central Research Station (NCRS) has begun replacing the 12- to 13-yr periodic inventory cycles for the states in the North Central region with annual inventories featuring measurement of approximately 20% of all plots in each of the 11 states each year. State reports on summaries of the forest resources will be produced every 5 yr. As a method of updating information on plots not visited in the current year, NCRS is developing nonlinear, individual-tree, distance-independent annual diameter growth models for species groups. The models, formulated as the product of an average diameter growth component and a modifier component, were calibrated on Minnesota FIA data from stands that were generally undisturbed, of mixed ages and of mixed species. The dependent variable is annual diameter growth. The independent variables include crown ratio, crown class, stand basal area, stand basal area larger than the subject tree, physiographic class, and latitude and longitude of plot locations. The model predictions at both the individual-tree level and plot level have negligible bias, and the models may be easily recalibrated to include new data sets obtained from the annual inventories. For. Sci. 47(30):301–310.

Landscape Change in the Midwest: An Integrated Research and Development Program

Abstract Contemporary patterns of landownership and development are changing the landscape of urban, suburban, and rural areas, fragmenting the forest resource base and raising concerns among a range of stakeholders. A new Landscape Change Integrated Research and Development Program of the USDA Forest Service. North Central Research Station, is examining the character, causes, and effects of these changes as well as the effectiveness of strategies aimed at stemming the negative consequences of landscape change.

Determination of the Electron Spin Density on the Phenolic Oxygen of the Tyrosyl Radical of Photosystem II

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTDetermination of the Electron Spin Density on the Phenolic Oxygen of the Tyrosyl Radical of Photosystem IIFrançois Dole, Bruce A. Diner, Curtis W. Hoganson, Gerald T. Babcock, and R. David BrittView Author Information Central Research and Development Department Experimental Station, E. I. du Pont de Nemours & Co. Wilmington, Delaware 19880-0173 Department of Chemistry, Michigan State University East Lansing, Michigan 48824-1322 Department of Chemistry, University of California Davis, California 95616 Cite this: J. Am. Chem. Soc. 1997, 119, 47, 11540–11541Publication Date (Web):November 26, 1997Publication History Received30 May 1997Revised9 September 1997Published online26 November 1997Published inissue 1 November 1997https://doi.org/10.1021/ja9717727Copyright © 1997 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views167Altmetric-Citations43LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (125 KB) Get e-AlertsSUBJECTS:Electrical properties,Electron density,Noncovalent interactions,Oxygen,Quantum mechanics Get e-Alerts

The τ-Nitrogen of D2 Histidine 189 is the Hydrogen Bond Donor to the Tyrosine Radical YD• of Photosystem II

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTThe τ-Nitrogen of D2 Histidine 189 is the Hydrogen Bond Donor to the Tyrosine Radical YD• of Photosystem IIKristy A. Campbell, Jeffrey M. Peloquin, Bruce A. Diner, Xiao-Song Tang, Dexter A. Chisholm, and R. David BrittView Author Information Department of Chemistry University of California Davis, California 95616 Central Research and Development Department Experimental Station, P.O. Box 80173 E. I. du Pont De Nemours & Company Wilmington, Delaware 19880-0173 Cite this: J. Am. Chem. Soc. 1997, 119, 20, 4787–4788Publication Date (Web):May 21, 1997Publication History Received25 February 1997Published online21 May 1997Published inissue 1 May 1997https://doi.org/10.1021/ja9706155Copyright © 1997 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views274Altmetric-Citations64LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (135 KB) Get e-AlertsSUBJECTS:Coupling reactions,Monomers,Nitrogen,Noncovalent interactions,Peptides and proteins Get e-Alerts

Role of Electronic Asymmetry in the Design of New Ligands: The Asymmetric Hydrocyanation Reaction

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTRole of Electronic Asymmetry in the Design of New Ligands: The Asymmetric Hydrocyanation ReactionT. V. RajanBabu and Albert L. CasalnuovoView Author Information Department of Chemistry, The Ohio State University 100 West 18th Avenue, Columbus, Ohio 43210 Central Research and Development Experimental Station, The DuPont Company Wilmington, Delaware 19880 Cite this: J. Am. Chem. Soc. 1996, 118, 26, 6325–6326Publication Date (Web):July 3, 1996Publication History Received20 March 1996Published online3 July 1996Published inissue 1 January 1996https://doi.org/10.1021/ja9609112Copyright © 1996 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views1428Altmetric-Citations122LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (113 KB) Get e-AlertsSupporting Info (2)»Supporting Information Supporting Information SUBJECTS:Chemical reactions,Ligands,Phosphorus,Selectivity,Stereoselectivity Get e-Alerts

Putting ground vibration predictions into practice : Pal Roy, P Colliery GuardV241, N2, March 1993, P63–67, 70

The blast vibration prediction model developed at the Central Mining Research Station (CMRS), India, simultaneously takes account of the decay of amplitude due to geometrical spreading and inelastic attenuation. The equations consider a zone of disturbance in terms of scaled distance beyond which vibrations will be zero elsewhere. The paper reports a study analysing data from 13 different coal and metal mines and one hyd-el project, in various parts of India, to assess the validation of the model. Three categories of operating mode were considered: surface blasting - surface measurements; surface blasting - underground measurements; and tunnel blasting - surface measurements. Values of site constants, correlation coefficient and index of determination for the 14 sites are presented. 2 refs., 5 figs., 2 tabs., 4 photos.

Control of Southern Green Stink Bug and Velvetbean Caterpillar on Soybean, 1992:

Abstract A small plot insecticide screening trial was conducted at the Central Research Station (Ben Hur Farm) near Baton Rouge, LA, to evaluate the efficacy of selected insecticides for control of SGSB and VBC. Plots measuring 4 rows (0.91 m row spacing) by 15 m were arranged in a randomized complete block design with 4 blocks. Insecticides were applied with a tractor and CO2-pressurized sprayer calibrated to deliver 93.5 liters/ha at 0.98 kg/cm2 through 8002 flat fan nozzles. Treatments were applied on 21 Sep to soybeans in the R5 plant growth stage. Kinetic surfactant (3.9 ml form, material/liter finished spray) was added to NTN 33893. Posttreatment samples consisted of one set of 25 sweeps per plot (38.2 cm diam sweep net) taken at 2, 7, 10, and 14 DAT.

Control of Heliothis Spp., 1988

Abstract The cotton cultivar ‘Paymaster 145’ was planted 24 May at the South Central Research Station at Chickasha, Okla. Planting rate was 20 lb/acre. Eight-row plots, 150 ft long, were arranged in a randomized complete block design with 3 replicates. Spray applications were made with a John Deere Hi-Cycle 6000 sprayer traveling at 4.5 mph. Insecticide applications consisted of 5.0 gal/acre at 40 psi with 1 no. 8 (Spraying Systems) nozzle/row. Applications were made 1, 8, 15, and 22 Aug. Plots were irrigated 21 Jul, 2 Aug, and 25 Aug, and rainfall occurred during the test as follows: 4 Aug, 0.77 inches; 9 Aug, 0.85 inches; 10 Aug, 0.12 inches; 19 Aug, 0.76 inches; 20 Aug, 0.17 inches; and 28 Aug, 0.12 inches for a total of 2.79 inches. Damage was estimated prior to spraying by collecting at random 100 fruits from the upper one-third of plants in each plot.

Productivity and Water Use of Proso Millet Grown under Three Crop Rotations in the Central Great Plains

AbstractProso millet (Panicum miliaceum L.) is a shallow‐rooted, short‐season summer annual that is well adapted to the semiarid conditions of the western Central Great Plains. However, cropping systems for proso millet have not been well established in this region. Three proso millet cultivars were grown under three crop rotations, millet‐millet (M‐M), winter wheat (Triticum aestivum L.) ‐millet (W‐M) and fallow‐millet (F‐M), for five growing seasons (1973–1977) to determine water use and productivity of the second component (proso millet) in each rotation. The research was conducted on a mesic Pachic Argiustoll soil at the Central Great Plains Research Station located near Akron, CO. Precipitation during the noncropped period for the W‐M and F‐M averaged 26 and 145% more, respectively, than the M‐M rotation. The W‐M and F‐M rotations exhibited 7 and 19% more seasonal crop water use, respectively, than the M‐M sequence over the 5‐yr period of the study. These differences in water use resulted in the W‐M and F‐M rotations producing 38 and 75% more total dry matter and 50 and 116% more grain yield, respectively, than the M‐M sequence. The three cultivars responded similarly to the three crop rotations. Since grain yields were low and variable for the M‐M rotation and the noncropped period was quite long (86 wk) and inefficient in soil water storage for the F‐M rotation, the W‐M rotation appears to be the most efficient rotation of the three rotations evaluated for producing proso millet in this region.

Chemical Control of the Cotton Bollworm and Tobacco Budworm in Oklahoma, 1987

Abstract Cotton was planted on 5 Tun at the South Central Research Station in Chickasha at 20 lb/acre of acid-delinted seed. Eight 200-ft row plots were arranged in a randomized block design with 3 replications. Spray applications were made with a John Deere Hi-Cycle 6000 sprayer traveling at a speed of 4.5 mph at 40 psi. Insecticide applications consisted of 5 gal total spray mixture/acre with 1 no. 8 (Spraying Systems) nozzle/row. Applications were made 6, 17, and 24 Aug and 3 Sep. Plots were irrigated on 7 and 25 Aug. Rainfall occurring during the test was as follows: 10 Aug, 0.42 inch; 14 Aug, 1.28 inch; 15 Aug, 0.05 inch; 24 Aug, 0.07 inch; 27 Aug, 1.60 inch; and 28 Aug, 0.02 inch for a total of 3.44 inches. Damage was estimated by collecting 100 fruit at random, prior to spraying from the upper one-third of plants in each plot.

Control of Insect Pests of Alfalfa in Oklahoma, 1986

Abstract Chemical treatments were applied on 2 Mar in a dryland field of “Arc” alfalfa on the South Central Research Station at Chickasha, OK. Controls for the alfalfa weevil, blue alfalfa aphid and pea aphid were evaluated. Chemicals were applied using a tractor drawn boom sprayer equipped with flooding nozzles and calibrated to deliver 20 gpa at 20 psi. Temperature at the time of application ranged from 60-70°F and winds were less than 5 mph. Plots were 4 x 7 m and arranged in a randomized complete block design with 4 replications. Population densities of weevil larvae were determined from 25 stem samples taken/plot on each posttreatment sampling date. Larvae were extracted from foliage with Berlese funnels and counts were calculated as larvae/stem. Pretreatment counts indicated an infestation level of 3.3 larvae/stem. Aphids were sampled by clipping 10 stems/plot on each date and washing aphids into a container of alcohol for counting. Initial aphid populations were less than i/stem.

Effect of Tillage Systems on Proso Millet Production1

AbstractProso millet (Panicum miliaceum L.) is well‐adapted for the Central Great Plains and could be planted in a winter wheat (Triticum aestivum L.)–millet‐fallow rotation, resulting in two crops in 3 yr. To determine the most suitable tillage system for proso millet production within this rotation, seven tillage management systems were evaluated over a 6‐yr period (1972–1977). The research was conducted on a mesic Pachic Arguistill soil on the Central Great Plains Research Station near Akron, CO. Comparisons included fall vs. spring tillage and replacing a tillage operation with herbicides. Controlling fall weed growth by tillage alone or with atrazine (2‐chloro‐4‐ethylamino‐6‐isopropylamino‐S‐triazine) increased grain yield of proso millet and protein content of the grain more than spring tillage for weed control. Increased millet production from fall tillage was attributed to increased soil NO−3‐N levels and increased soil water use by millet. Water use efficiency by millet was also increased with fall tillage. Adding N fertilizer decreased millet grain production.

Relocation of the Koyna earthquakes with a new velocity model

abstractHypocenter locations of 380 earthquakes of magnitude ≧ 3 in the Koyna region, recorded by the Central Water and Power Research Station Network of Seismological Observatories and the India Meteorological Department stations during the period December 1967 to December 1973, are determined after selection of an appropriate crustal model. The model is chosen from among the few available for the region on the basis of comparatively better hypocenter locations in terms of error parameters in the location of 32 events of magnitude ≧ 4 (master events). An epicenter map and hypocentral depth cross-section of the earthquakes in the region are presented. Least-squares fit through the best hypocentral locations along the line perpendicular to the strike of fault plane inferred by Tandon and Chaudhury (1968) gives a dip of 27° in the east-southeast direction and the surface manifestation of the fault 25 km to the west of the Koyna Dam. While the chosen strike direction of the fault is also in agreement with those obtained in a number of fault plane solutions and LANDSAT imagery (Lee and Rayleigh, 1969; Sykes, 1970; Banghar, 1972; Chandra, 1976; Rastogi and Talwani, 1980; Langston, 1981), the observed dip direction of the fault agrees only with the results of deep seismic sounding (Kaila et al., 1979) and the fault plane solution of Rastogi and Talwani (1980). The amount of dip is, however, much less than any of the values reported so far.

Control of Alfalfa Weevil Larvae in Oklahoma, 1985

Abstract Two evaluations were conducted to determine efficacy of insecticides against the weevil. The first of these was located on the South Central Research Station at Chickasha, OK with the cultivar ‘Arc’. Pretreatment counts made just before spraying on Mar 24 indicated an infestation level of 4.5 larvae/stem. The second evaluation was conducted on ‘Riley’ alfalf; at the Agronomy Research Station, Stillwater. Treatment date for this test was 6 Apr with pretreatment counts averaging 15 larvae/stem. Applications were made with a tractor-drawn boom sprayer equipped with flooding nozzles and calibrated to deliver 20 gal/acre at 20 psi. Plots were 4 × 7m and arranged in a randomized complete block design with 4 replications. Population densities of larvae were determined from 25 stem samples taken from each plot on each posttreatment sampling date. Larvae were extracted from foliage with Berlese funnels prior to counting. Counts wert divided by 25 to give tabular values in larvae/stem.