- Squash -

SQUASH AND PUMPKIN

CONTROLLING SQUASH BUGS ON PUMPKIN WITH FOLIAR APPLICATIONS, OKLAHOMA, 2001: 

Squash bug (SB): Anasa tristis (De Geer)              

Pumpkin was direct seeded to a field at the Wes Watkins AREC, Lane, on 10 Jul.  The experimental design was a randomized complete block with 8 treatments and 5 replicate blocks with plots on 9 ft row spacing, 20 ft long with 20 ft alleys cut between plots in rows.  Plants were thinned to a 36 inch spacing in plots.  Plots were treated on 15, 21, 29 Aug and 13 Sep using a tractor –mounted sprayer with 3 hollow-cone nozzles per row, 1 directed over the row and 1 on each side of the row on drops directed at an angle into the crop canopy.  The sprayer was operated at 40 psi and delivered 20 gal/acre.  Plots treated with Actara were treated on only one date, 15 Aug.  Surveys to determine insect abundance were conducted at approximately 7 day intervals by examining three 1.5 ft² randomly selected areas of plant foliage within each plot.

Squash bugs were not abundant and did not begin to increase in numbers until  Aug.  Surveys of plots 5 days after the first application of treatments indicated that application of Capture resulted in significant reductions of squash bugs in comparison to the untreated plots.  All treatments except SpinTor and Actara resulted in significantly fewer squash bugs per plant as compared to the untreated plots as determined by surveys on 9/21 as conducted after a total of 4 applications.  Actara was applied to plots on only one date, 15 Aug.  No squash bugs were found on plants in plots treated with Capture, Warrior and MetasystoxR on 9/21.

                                                            No. squash bugs     

Mean values in columns followed by the same lower case letter are not significantly different, LSD, P=0.1.

SQUASH:  Cucurbita pepo L., ‘Lemondrop’                      

RESIDUAL ACTIVITY OF FOLIAR APPLIED INSECTICIDES FOR CONTROLLING SQUASH BUG, 2002 

jedelson-okstate@lane-ag.org

Squash bug (SB): Anasa tristis (De Geer)              

Squash was direct seeded to a field at the Wes Watkins AREC, Lane, on 15 Aug.  The experimental design was a RCB with 12 treatments and five replicate blocks with plots on nine ft row spacing, 20 ft long with 20 ft alleys cut between plots in rows.  Plants were thinned to a 12 inch spacing in plots.  Plots were treated on 15 Sep using a tractor –mounted sprayer with three hollow-cone nozzles per row, one nozzle directed over the row and one nozzle on each side of the row on drops directed at an angle into the crop canopy.  The sprayer was operated at 40 psi and delivered 20 gal/acre.  Bioassays were conducted by placing adult female squash bugs in plastic 1 oz creamer cups and clipping them to the bottom of a lower crown leaf on one plant in each plot.  Mortality of bugs was assessed after 24 hours.  Data were analysed using ANOVA and LSD to make comparisons among treatments.

Squash bugs were not abundant and therefore adult bugs from a laboratory culture were used to bioassay residual activity of insecticides 24 hours after applications.  Disulfoton and thiamethoxam were the only insecticides that resulted in significant mortality of adult squash bugs.  Both of these insecticides are systemic and as expected were active when adult squash bugs were caged on the lower side of leaves 24 hours after the application of insecticides.  Based on these results we predict that foliar applications of disulfoton and thiamethoxam will provide the best residual control of adult squash bugs moving within and among plants in fields.

 Table 1.                                                          

Treatment                                 Rate                        Per cent mortality          

disulfoton                      0.5 lb ai / acre                        80   a

endosulfan                    1.0 lb ai/acre                            0    c

spinosad                       0.125 lb ai/acre                        0    c

bifenthrin                      0.10 lb ai/acre                           0    c

l-cyhalothrin                  0.02 lb ai/acre                         33   bc

thiamethoxam               0.06 lb ai / acre                        60   ab

imidacloprid 1.6       3.75 oz / acre                               20    c

Assail                           0.1 lb ai / acre                          20    c

Calypso                        6 oz / acre                                 0     c

Novaluron                    10.5 fl oz / acre                       20    c

Fulfill    50WP              2.75 oz / acre                            0     c

untreated                                  --                                  0     c              

Mean values in columns followed by the same lower case letter are not significantly different, LSD, P = 0.1.

SQUASH:  Cucurbita pepo L., ‘Lemondrop’                      

EVALUATION OF  SYSTEMIC INSECTICIDE RESIDUAL ACTIVITY FOR CONTROLLING SQUASH BUG ON SEEDLING SQUASH, 2002: 

jedelson-okstate@lane-ag.org

Squash bug (SB): Anasa tristis (De Geer)          

Squash was direct seeded to plots on 2 Sep at the Wes Watkins AREC, Lane, OK.  The experimental design was a RCB with five replicates and three treatments.  Plots were 1 row wide (72 inches) and 10 ft long with six inch plant spacing within the row. Plots were treated at planting with insecticides using two cultivator knives with injection tubes attached at set at eight inch spacing attached to a CO2 powered bicycle sprayer with an output of 49.5 GPA @ 30 psi.  Once a week for three weeks beginning at the 2-true leaf stage one adult squash bug from a laboratory maintained culture was caged on the underside of a leaf using leaf clip cages.  The squash bugs were monitored at 24 and 48 hours for mortality.   Data was summarized as a calculated per cent mortality and analysed using ANOVA and a LSD means comparison test.

At the 2-true leaf stage, 18 Sep, Furadan treatments resulted in 80% mortality while Admire treatments resulted in 40% mortality at 48 hr after caging adults on seedlings.  At 24 and 32 days after planting and treatment applications there were no significant effects from either insecticide.  Furadan provided significant levels of activity for controlling adult squash bugs through the seedling stage of growth.

Treatment/        Rate                                                                             % Mortality         

Furadan                 2.4 fl oz                  9/18/02                    80a                        100a      

Admire                  2.2 fl oz                  9/18/02                    80a                          40b        

Untreated               -                            9/18/02                    0  b                          0 b       

Furadan                 2.4 fl oz                  9/25/02                    20a                         40a        

Admire                  2.2 fl oz                  9/25/02                    20a                         20a        

Untreated               -                            9/25/02                     0 a                          0  b      

Furadan                 2.4 fl oz                  10/3/02                    20a                         40b        

Admire                  2.2 fl oz                  10/3/02                    20a                         20a         

Untreated               -                            10/3/02                    0 a                         20a        

Mean values in a column for individual dates, followed by the same letter are not significantly different (LSD;P = 0.1).

Treatment/                    Rate                                                                                    % Mortality

Furadan                        2.4 fl oz                     9/18/02                        80a                  100a

Admire                         2.2 fl oz                     9/18/02                        80a                  40b

Untreated                        -                             9/18/02                        0b                    0c

Furadan                        2.4 fl oz                     9/25/02                        20a                  40a

Admire                         2.2 fl oz                     9/25/02                        20a                  20a

Untreated                        -                             9/25/02                        0a                    0a

Furadan                       2.4 fl oz                     10/3/02                        20a                  40a

Admire                        2.2 fl oz                      10/3/02                        20a                  20a

Mean values in a column for individual dates, followed by the same letter are not significantly different (LSD;P = 0.1).

SQUASH:  Cucurbita pepo L., ‘Lemondrop’ 

GREENHOUSE BIOASSAYS WITH SOIL APPLIED FLONICAMID FOR DETERMINING TOXICITY TO THE SQUASH BUG, 2002 

Squash bug (SB):  Anasa tristis (DeGeer)

            Squash seedlings grown in pots in a greenhouse at the Wes Watkins AREC, Lane, OK, were treated with insecticides and then adult squash bugs were caged on plants to evaluate toxicity of the treatments.  Seeds were planted in 9 inch diam pots filled to within 1 inch of the rim with a commercial potting soil media.  Pots were held in a greenhouse at approx. 75^o F.  When all seedlings had germinated and reached the one true-leaf stage the pots were treated with insecticides.  Differing rates of flonicamid were mixed using dilutions with water and 1.5 fl oz of each treatment rate solution was poured and evenly distributed over the soil in the pots.  The rates were:  0, 0.1X, 1.0X and 10X with the 1.0X rate calculated as equivalent to a 0.088 lb ai/acre solution applied to individual plants.  Solutions were mixed by dissolving 1 gram 50WP flonicamid in 100 ml distilled water and the 10X solution applied by taking 1 ml of the stock solution and placing it in 50 ml water to apply to individual pots.  The 1X and 0.1X rate solutions were mixed by diluting the 10X stock solution.  The experimental design was a CRD with four replicates of each treatment.  Two days after treatment, cages were placed over individual pots and one female adult squash bug was placed in each cage and the top of the cage closed with mesh cloth.  Caged pots were monitored at 2, 4, 6 and 8 DAT and number of dead squash bugs recorded.  Data were subjected to ANOVA and regression analysis to determine relationships between treatment rates and mortality.

            There was no significant relationship between rate and mortality and no differences in mortality at any treatment rate in comparison to the untreated control (0.0 rate).

SQUASH:  Cucurbita pepo L., ‘Lemondrop’                      

FOLIAR APPLIED INSECTICIDES FOR CONTROLLING SQUASH BUG, 2003 

Squash bug (SB): Anasa tristis (De Geer)              

Squash was direct seeded to plots on 14 Jul at the AREC, Lane, OK.  The experimental design was a RCB with five replicates and 14 treatments.  Plots were 1 row (36 inches) by 15 ft long with 15 ft of untreated plants between plots.  Plots were treated with insecticides using an ATV-mounted CO₂ powered sprayer with drops and an output of 32.2 gpa at 45 psi.  The spray application was broadcast with 3 hollow cone nozzles per row.  Plots were treated on 29 Jul.  Plants in 39 inches in each treated row were visually inspected for adult and nymph SB on 1 Aug, 5 Aug, and 8 Aug.  At 14 DAT 3 plants per plot were measured to determine height of plants as a measure of plant growth as affected by control of squash bug populations.  Squash bug data were transformed to log10+1 variables and squash bug and plant height data were then subjected to ANOVA and a means separation test to determine treatment effects.  Data reported in Table 1 are non-transformed mean values of total number of squash bugs per 39 row inches. 

Squash bug populations were abundant and their feeding resulted in death of plants in the untreated plots by the end of the trial.  At 3 DAT Capture, Warrior, Danitol, Actara, and Diamond applications resulted in significant reductions in populations in comparison to the untreated plots.  At 7 DAT these same insecticides in addition to Meta-systox R and Assail resulted in significant reductions in numbers.  At 10 DAT all insecticide applications with the exception of Avaunt and flonicamid resulted in significant reductions in total number of squash bugs in comparison to untreated plots.  The pyrethroid insecticides resulted in short and long term significant activity against the squash bug.  Meta-systox R and the nicotinoid insecticides provided significant reductions but took longer to effect the populations.  Plants in plots treated with the pyrethroid insecticides Capture and Warrior were the least damaged by squash bugs as determined by plant height.  Plants in all plots treated with insecticides except Spintor were taller than plants in the untreated plots indicating less damage by squash bugs and that the insecticides provided significant control of squash bug damage.

Table 1.

                                      Rate                                   Number of SB / 39 inches row  

Treatment                        amt/acre                               (3 DAT)          (7 DAT)            (10DAT) 

Spintor 2SC                   0.125 lb (AI)                        13.2  bcd          12.0 abcde            8.8 bc             

Thiodan 2 EC                    1.0 lb (AI)                         9.2   abc            18.0 ab                 6.8   cd           

Metasystox-R 2 EC           0.5 lb (AI)                         8.4   ab                3.6    e                 3.0   cd           

Capture 2 EC                     0.1 lb (AI)                         6.2    ef                4.2    e                 5.0   cd           

Warrior SC                       0.02 lb (AI)                        2.0     f                  3.0     de             0.4     e           

Danitol 2.4 EC                    0.3 lb (AI)                        2.8    def               8.8    cde             0.8   de              

Actara 25WG                    0.06 lb (AI)                        4.4    def              5.4     e                4.0   c             

Provado 1.6 F                    3.75 fl oz                           4.6  bcde             19.8    a                7.0   cd           

Assail 70 WP                       0.1 lb (AI)                       5.2    cdef              4.6     de             3.6   c                

Calypso 4 F                          0.1 lb (AI)                      5.4   cdef               8.2   abcde         4.6  bc              

novaluron                          0.078 lb (AI)                      3.0     def               5.6    cde           4.4  bc              

Avaunt 30 DG                   0.065 lb (AI)                   11.0   abcd               6.2   bcde          8.0 ab              

flonicamid                           0.071 lb (AI)                  16.0    a                   16.2  abc          18.0 a             

Untreated check                        -                              11.2    abc               15.0 abc           17.2 a                         

Mean values in a column followed by different letters are significantly different, LSD, P=0.1.

Table 2.

                                      Rate                                   Height (inches)

Treatment                        amt/acre                               of plants at 14 DAT

Spintor 2SC                        0.125 lb (AI)                        17.8    d          

Thiodan EC                        1.0 lb (AI)                             28.2   c           

Meta-systox R                    0.5 lb (AI)                            29.2  bc          

Capture 2EC                      0.1 lb (AI)                            35.3 a             

Warrior SC                        0.02 lb (AI)                          34.2 ab           

Danitol                               0.3 lb (AI)                            25.9   c           

Actara 25WG                    0.06 lb (AI)                          25.9   c           

Provado 1.6                      3.75 fl oz                              27.5   c           

Assail                                0.1 lb (AI)                            24.7   c           

Calypso                            0.1 lb (AI)                            27.7   c           

Diamond                          0.078 lb (AI)                        25.0   c           

Avaunt                             0.065 lb (AI)                        28.8   c           

Flonicamid                       0.071 lb (AI)                        26.4   c           

Untreated check                         -                               18.8    d                                    

Mean values in a column followed by the different letters are significantly different, LSD, P=0.1.

SQUASH:  Cucurbita pepo L., ‘Lemondrop’

Squash bug (SB): Anasa tristis (De Geer)

CONTROLLING SQUASH BUG ON SQUASH WITH FOLIAR APPLICATIONS, OKLAHOMA, 2000:  Squash was direct seeded to a field at the Wes Watkins AREC, Lane, on 29 Jun.  The experimental design was a RCB with 9 treatments and 5 replicate blocks with plots on 6 ft row spacing, 20 ft long with 20 alleys cut between plots in rows.  Plants were thinned to a 6 inch spacing in plots.  Plots were treated on 1, 8 and 21 Aug using a tractor –mounted sprayer with 3 hollow-cone nozzles per row, 1 directed over the row and 1 on each side of the row on drops and directed at an angle into the crop canopy.  The sprayer was operated at 40 psi and delivered 20 gal/acre.  Plots treated with thiamethoxam were treated on only one date, 1 Aug.  Surveys to determine insect abundance were conducted at approximately 7 day intervals by examining 3 plants per plot.

Insects were not abundant and did not begin to increase in numbers until 16 Aug.  Numbers in untreated plots increased through 29 Aug.  All treatments except Provado and thiamethoxam resulted in significantly reduced numbers of nymphs and adults in comparison to untreated plots. 

                                                            Nymphs                                              

Treatment and rate/acre                       16 Aug             24 Aug             29 Aug

Untreated                     -                         8  bc              28 ab               25 a

Meta Systox                 0.5 lb AI          1   cd                2      de          0    c

Diazinon                       2 pints                0     d               1      de          0    c

Capture                        6.4 oz                 2  bcd                          1      de              2  bc

Warrior                        0.02 lb AI          0      d              0        e            0    c

Lannate                        1 lb AI               2  bcd                          3      de              1    c

Thiodan                        2 lb AI               2  bcd                          9    cd                2   bc

Provado                       3.75 oz             18 a                 18  bc              14 ab

thiamethoxam                  0.02 lb AI        16 ab               53 a                 22 a                            

Means in a column followed by the same letter are not significantly different, LSD, P=0.1.

                                                            Adults                                                             

Treatment and rate/acre                       16 Aug             24 Aug             29 Aug

Untreated                     -                       2 a                   8 a                   7 a

Meta Systox                 0.5 lb AI        1  bc                1   cd               3   b

Diazinon                       2 pints              1 abc                1   cd               3   b

Capture                        6.4 oz               0    c                0     d               1   b

Warrior                        0.02 lb AI        0    c                0     d               0   b

Lannate                        1 lb AI            2 ab                 1   cd               2   b

Thiodan                        2 lb AI            1 abc                0     d               2   b

Provado                       3.75 oz             3 a                   4  bc                4 ab

thiamethoxam                 0.02 lb AI        1 abc                7 ab                 5 a                              

Means in a column followed by the same letter are not significantly different, LSD, P=0.1.

SQUASH:  Cucurbita pepo L., ‘Lemondrop’                       J.V. Edelson, J. Duthie, and W. Roberts

Squash Bug: Anasa tristis (De Geer)               Oklahoma State University

                                                                                                Lane, OK 74555

CONTROL OF SQUASH BUGS ON SQUASH WITH SOIL APPLIED INSECTICIDES, OKLAHOMA, 2000:  A field was direct seeded with squash on 29 Jun at the Wes Watkins AREC, Lane, OK.  The experimental design was a RCB with 5 treatments and 5 replicate blocks.  Plots were 6 ft wide with one row, 20 ft long with plant spacing of 6 inches and had 20 ft alleys between plots in rows.  Soil insecticides were applied by spraying insecticides over the seed furrow immediately following planting on 29 Jun. Plots were irrigated following insecticide application.  Admire was applied to one set of treatment plots when plants had approximately 5 true leaves at the last cultivation on 28 Jul by spraying a band to the side of the plants.  Thiodan was applied to the foliage in one set of plots on 18 Aug.  Insect abundance was determined by examining 3 plants per plot on approximately 7 day intervals.  A bioassay was conducted by placing cages with 1 adult squash bug over single plants in plots on 12 Jul and then examining the cages for bug mortality at 24 and 48 hr.

Insects were not abundant early in the growing season when it was expected that the main direct effects of the soil applied insecticides would be noted.  By mid to late season there were no significant reductions in squash bug abundance in the treatments except that in which Admire was applied on 28 Jul.  Results indicate that a mid season application of Admire can reduce squash bug abundance through the season.  Results of the bioassays conducted approximately 13 days after planting indicated that thiamethoxam applications resulted in significant mortality of squash bug adults caged on plants.

Table 1.

                                                            Mean no. nymphs / 3 plants              

Treatment and rate                              7 Aug               16 Aug             22 Aug

Furadan 2.4 fl oz/1000 ft                     11                    19 a                 28 a

¹Furadan+Admire                               

            2.4 fl oz +2.4 fl oz/1000 ft           2                      0.4  c                 4  b   

thiamethoxam 0.04 oz AI/330 ft            7                      9  bc              13 ab

Thiodan 1 lb AI/acre                         10                    20 a                   9 ab

untreated                                                5                    18 a                 19 ab  

Means in a column followed by the same letter are not significantly different, LSD, P=0.1. 

¹Furadan was applied at planting and Admire was applied when plants had 5 true leaves.

Table 2.

                                                Mean no. adults / 3 plants                         Bioassay mortality

Treatment and rate                  7 Aug               16 Aug             22 Aug             12 Jul              

Furadan 2.4 oz/1000 ft         2 a                   1   b                 3                        0      b

¹Furadan+Admire                    0.2  b               0   b                 2                        0      b

            2.4 fl oz +2.4 fl oz/1000 ft

thiamethoxam                           2 a                   1   b                 5                      80% a

Thiodan foliar                           1 ab                 6 a                   6                        0      b

untreated                                  1 ab                 4 a                   5                      20%   b         

Means in a column followed by the same letter are not significantly different, LSD, P=0.1. 

¹Furadan was applied at planting and Admire was applied when plants had 5 true leaves.

SQUASH:  Cucurbita pepo L., ‘Lemondrop’                       J.V. Edelson, J. Duthie, and W. Roberts

Squash Bug: Anasa tristis (De Geer)               Oklahoma State University

                                                                                    Lane, OK 74555

EFFICACY OF SOIL APPLIED INSECTICIDES FOR CONTROLLING INSECTS ON SQUASH, OKLAHOMA, 2000.   Squash was direct seeded to a field at the Wes Watkins Agricultural Research and Extension Center, Lane, OK. on 20 Jul.    Plots for this experiment were measured and marked using a RCB design with 5 replicate blocks and 8 treatments and each plot measured 12 ft wide by 50 ft long with one row per plot.  Insecticides were applied to a 7 inch band over the seed furrow in the plots prior to planting with the exception of Warrior which was applied as a foliar spray on 4 Aug.  Plants were thinned to 3 ft intervals after plants reached the 3-true leaf stage.  Plots were examined at 7 day intervals and number of cucumber beetles, squash bugs, cutworms, number of leaves per plant and number of plants in 10 row ft were recorded.  Fruit yield in each plot was determined at maturation and roots from 3 plants per plot were examined for insect feeding damage.  Additionally, bioassays were conducted by caging adult squash bugs on individual plants on 10 and 16 Aug. 

There were few insect pests present in fields during the spring of 2000 and therefore no significant conclusions can be reached concerning direct effect of the insecticides on insect pest populations.  The following tables provide a summary of plant growth as number of leaves per plant and plant stand.  Both variables provide indirect evidence of plant stand health as affected by use of insecticides and their effect on insects that can be missed during standard surveys. There were no significant differences noted in plant growth as determined from number of leaves per plant.  There was no significant effect on plant stand as determined from plant stand counts after germination and prior to plant thinning nor were there significant differences in plant stand counts after thinning plants.  There was no measurable damage to plant roots in any plots.  There were no significant differences among treatments in weight of fruit harvested from 3 plants per plot on 12 Sep.  Results of bioassays indicated that diazinon and foliar applications of Warrior provided signficant mortality of squash bug adults after 48 hr on plants on 10 Aug. 

Table 1.

                                                Mean no. leaves/plant             Mortality BioassayResults

Treatment and Rate                 7 Aug               14 Aug            1            10 Aug             16 Aug

Aztec 6.7 oz                             2                      7                      0       b            0

thiamethoxam 0.12 oz AI            2                      5                      0       b            0

diazinon 4lbs AI/acre             2                      6                      60% a              25%

Lorsban 13 lbs AI/acre 2                      7                      0       b            0

Admire 2.4 oz                          2                      6                       0       b            25%

Warrior 0.03 lb AI/acre 2                      7                      60% a              0

untreated                                  2                      6                      0      b             0        

Means in a column followed by the same letter are not significantly different, LSD, P=0.1.

Rates expressed as material per 1000 row ft unless otherwise noted.

Table 2.

                                                Mean no. plants/50 ft

Treatment and Rate                 7 Aug               14 Aug

Aztec 6.7 oz                             76                    14

thiamethoxam 0.12 oz AI             78                    11

diazinon 4lbs AI/acre                         72                    11

Lorsban 13 lbs AI/acre             67                    12

Admire 2.4 oz                         77                    11

Warrior 0.03 lb AI/acre 63                    11

untreated                                  74                    13                   

No significant differences among treatments on either date.

Rates expressed as material per 1000 row ft unless otherwise noted.

SQUASH:  Cucurbita pepo L., ‘Lemondrop’                                  

            Squash bug (SB); Anasa tristis (De Geer)                       

            CONTROL OF SQUASH BUG ON SUMMER SQUASH, 1999:  Squash was direct seeded to plots on 7 Jul at the AREC, Lane, OK.  The experimental design was a RCB with 4 replicates and 10 treatments.  Plots were 1 row (72 inches) by 20 ft long with 20 ft alleys between plots.  Plots were treated with insecticides using a tractor-mounted sprayer with an output of 35 gal/acre at 40 psi.  The spray application was broadcast with 6 hollow-cone nozzles (TXVS-26) per row.  Plots were treated on 20 and 29 Jul and 10 Aug.  Three plants per plot were visually examined on 23, 28 Jul and 4, 12, and 16 Aug to determine SB abundance.  Data were subjected to ANOV and a means separation test to determine treatment effects.

            SB abundance increased throughout the period of time that applications were made to plots and numbers were very high on the date of the last survey (12 Aug).  Meta-systox R at the middle and high rates, Neemix, Warrior, thiamethoxam and Provado applications resulted in significant reductions in SB abundance in comparison to untreated plots at the end of the growing season as determined by surveys conducted on 12 Aug.

Means in a column followed by the same letter are not signicantly different (LSD, P=0.1).

^a Squash bug adults and nymphs.

SQUASH:  Cucurbita pepo L. 'Lemon drop'

  Squash bug (SB); Anasa tristis (De Geer)              

Green peach aphid (GPA): Myzus persicae (Sulzer)         

            CONTROL OF INSECTS ON SUMMER SQUASH, 1998: Summer squash was direct seeded on 29 Jul at the Wes Watkins Agricultural Research and Extension Center, Lane, OK.  The experimental design was a CRD with 5 replicates and 8 treatments.  Plots were 1 row wide (72 inches) and 10 ft long with 6 inch plant spacing within the row.  Plots were treated with insecticides using a tractor-mounted sprayer with a broadcast application of 72 inches from 6 hollow-cone nozzles applying 41 gpa at 40 psi.  Plots were treated with all insecticides except thiamethoxam on 24 and 31 Jul, 7 and 14 Aug.  Plots were treated with thiamethoxam on 24 and 31 Jul.  Insect  populations were surveyed on 28 Jul, 3, 10 and 17 Aug by counting insects present on 3 plants per plot.

            Treatments were initiated when squash bugs were in low abundance.  Populations of SB increased and were very abundant in untreated plots by 17 Aug.  All treatments resulted in reduced numbers of SB in comparison to the untreated plots. Each of the insecticides evaluated provided good control of SB.  Aphids were more abundant in the plots treated with Warrior than in all other treatment plots.

                                                            Mean no. insects per 3 plants                                               

Numbers in a column followed by the same letter are not significantly different, LSD, P = 0.1.

SQUASH:  Cucurbita pepo L.  ‘Lemon drop’

            Squash bug; Anasa tristis (DeGeer)

CONTROL OF SQUASH BUG ON SUMMER SQUASH IN OKLAHOMA, 1997:  Summer squash, ‘Lemon drop’, was directed seeded in Jul at the Lane AREC, Lane, OK.  The experimental design was a RCB with 5 replicates and 10 treatments.  Plots were 2 rows wide (72 inches) and 20 ft long with 20 ft alleys cut between plots.  Plots were treated with insecticides using a tractor mounted sprayer with a broadcast application of 72 inches from 5 hollow cone nozzles applying 35 gal / A at 43 psi.   Plots were treated on 14 and 25  Aug.  Squash bug populations were surveyed on 18 and 28 Aug by counting adults and nymphs on 3 plants per plot.

Squash bugs were abundant throughout the evaluation period.  All treatments  except Dibrom resulted in reduced numbers of adults on 18 Aug.  Asana and Diazinon treatments reduced numbers of nymphs on 18 Aug.  Total numbers of squash bugs were significantly reduced with one application of Asana, Diazinon, Lannate, Thiodan and MetaSystox R in comparison to untreated plots at 4 DAT.  All treatments except Sevin, Guthion and Dibrom resulted in reduced numbers of squash bugs at 3 days after the second treatments.