An illustrated version of this guideline is available online at http://ipm.ucdavis.edu/PMG/selectnewpest.cucurbits.html
Publication 3445
UC Statewide Integrated Pest Management Program
Cucurbits May 2016
PEST MANAGEMENT GUIDELINES FOR AGRICULTURE
Contents (Dates in parenthesis indicate when each topic was updated)
Cucurbits Year-Round IPM Program (Reviewed 10/11) ........................................................................................................................ iv
General Information (Section reviewed 12/09) .........................................................................................................................................1
Biological Control (12/09) ...........................................................................................................................................................................1
Pesticide Registrations (12/09) ...................................................................................................................................................................1
Relative Toxicities Of Pesticides Used In Cucurbits To Natural Enemies And Honey Bees (5/16) ........................................................................2
Insects and Mites (Section reviewed 12/09) ...............................................................................................................................................5
Armyworms (5/16) ......................................................................................................................................................................................5
Cabbage Looper (5/16) ................................................................................................................................................................................7
Crickets (5/16) ...........................................................................................................................................................................................10
Cucumber Beetles (5/16) ..........................................................................................................................................................................12
Cutworms (5/16) .......................................................................................................................................................................................14
Darkling Beetles (5/16) ..............................................................................................................................................................................16
Driedfruit Beetles (11/05) ..........................................................................................................................................................................17
European Earwig (5/16) ............................................................................................................................................................................18
False Chinch Bug (5/16) ............................................................................................................................................................................19
Flea Beetles (5/16) ......................................................................................................................................................................................20
Grasshoppers (5/16) .................................................................................................................................................................................22
Green Peach Aphid (5/16) ........................................................................................................................................................................23
Leafhoppers (5/16) .....................................................................................................................................................................................26
Leafminers (5/16) .......................................................................................................................................................................................28
Melon Aphid (5/16) ...................................................................................................................................................................................31
Seedcorn Maggot (5/16) ............................................................................................................................................................................34
Spider Mites (5/16) ...................................................................................................................................................................................36
Squash Bug (5/16) ......................................................................................................................................................................................38
Stink Bugs (5/16) .......................................................................................................................................................................................40
Thrips (5/16) ..............................................................................................................................................................................................42
Vinegar Flies (11/05) .................................................................................................................................................................................44
Whiteflies (5/16) ........................................................................................................................................................................................45
Wireworms (5/16) .....................................................................................................................................................................................49
Diseases (Section reviewed 12/09) .............................................................................................................................................................51
Angular Leaf Spot (5/16) .........................................................................................................................................................................51
Anthracnose (5/16) ...................................................................................................................................................................................52
Bacterial Fruit Blotch (11/05) ....................................................................................................................................................................53
Charcoal Rot (6/12) ...................................................................................................................................................................................54
Downy Mildew (5/16) ..............................................................................................................................................................................55
Fusarium Crown And Foot Rot (12/09) ..................................................................................................................................................57
Fusarium Wilt (Cantaloupe) (6/12) ........................................................................................................................................................58
Fusarium Wilt (Watermelon) (6/12) .......................................................................................................................................................58
Measles (11/05) ..........................................................................................................................................................................................59
Powdery Mildew (5/16) ...........................................................................................................................................................................60
Root Rots (Damping-Off) (5/16) .............................................................................................................................................................62
Sudden Wilt (6/12) ....................................................................................................................................................................................64
Verticillium Wilt (6/12) ............................................................................................................................................................................65
Vine Decline (Crown Blight) (5/16) .........................................................................................................................................................66
Yellows (Molybdenum Deficiency) (11/05) ...........................................................................................................................................68
Viruses (Section Reviewed 12/09) ..............................................................................................................................................................69
Cucumber Mosaic (12/09) .........................................................................................................................................................................69
Cucurbit Aphid-Borne Yellows (6/08) ....................................................................................................................................................69
Cucurbit Yellow Stunting Disorder (6/08) ............................................................................................................................................70
Curly Top (12/09) ......................................................................................................................................................................................72
UC IPM Pest Management Guidelines - CUCURBITS
May 2016 ii
Potyviruses (6/12) .....................................................................................................................................................................................72
Squash Mosaic (6/08) ................................................................................................................................................................................73
Nematodes (Section reviewed 5/16) ..........................................................................................................................................................74
Weeds (Section reviewed 12/09) .................................................................................................................................................................77
Integrated Weed Management (7/13) ....................................................................................................................................................77
Organic Weed Control In Cucurbits (6/12) ............................................................................................................................................80
Special Weed Problems (6/12) ................................................................................................................................................................82
Common And Scientific Names Of Weeds (12/09) ...............................................................................................................................83
Susceptibility Of Weeds To Herbicide Control (7/13) .........................................................................................................................84
Herbicide Treatment Table (5/16) ...........................................................................................................................................................86
Precautions for Using Pesticides .................................................................................................................................................................90
UC IPM Pest Management Guidelines - CUCURBITS
(10/11) Cucurbits Year-Round IPM Program Annual Checklist iii
Download this checklist at http://ipm.ucdavis.edu/FORMS/
Authors
Insects and Mites: E. T. Natwick, UCCE Imperial Co.; J. J. Stapleton, UC IPM Program, Kearney Agricultural
Center, Parlier; C. S. Stoddard, UCCE Merced & Madera counties
Diseases: R. M. Davis, Plant Pathology, UC Davis; T. A. Turini, UCCE Imperial Co.; B. J. Aegerter, UCCE San
Joaquin Co.; J. J. Stapleton, UC IPM Program, Kearney Agricultural Center, Parlier
Nematodes: J. O. Becker, Nematology, UC Riverside; B. B. Westerdahl, Nematology, UC Davis
Weeds: C. S. Stoddard, UCCE Merced & Madera counties
Crop Leadership Team: C. S. Stoddard, UC Cooperative Extension Merced & Madera counties (crop team
leader); P. B. Goodell, UC IPM Program (IPM facilitator); R. DeBiase, UC IPM program (coordinator); J. O.
Becker, Nematology, UC Riverside; E. T. Natwick, UC Cooperative Extension, Imperial County; T. A. Turini,
UC Cooperative Extension, Imperial County
Acknowledgments for contributions
Insects and Mites: R. L. Coviello, UCCE Fresno Co.; C. B. Fouche, UCCE San Joaquin Co.; L. D. Godfrey,
Entomology, UC Davis; . B. LeBoeuf, AgiData Sensing, Inc., Fresno; JM. Murray, UCCE Colusa and Glenn
counties; C. G. Summers, Entomology, UC Davis and Kearney Agricultural Center, Parlier
Diseases: W. D. Gubler, Plant Pathology, UC Davis
Diseases (Cucurbit Yellow Stunting Disorder Virus): R. L. Gilbertson, Plant Pathology, UC Davis; W. M.
Wintermantel, USDA, ARS, Salinas, CA
Nematodes: U. C. Kodira, Nematology, UC Davis
Weeds: C. E. Bell, UCCE San Diego Co.; W. T. Lanini, Plant Sciences and Weed Science, UC Davis
Year-Round IPM Program Development: J. L. Azulai, UC IPM Program, Davis; D. Henderson, UC Cooperative
Extension, Imperial County (currently at Monsanto); W. T. Lanini, Weed Science and Plant Sciences, UC
Davis; T. A. Martin, UC IPM Program, Davis
About this publication
Produced and edited by:
UC Statewide IPM Program
University of California, Davis
Guidelines Coordinator: R.DeBiase
Production: F. Rosa
This publication has been anonymously peer reviewed for technical accuracy by University of California
scientists and other qualified professionals. This review process was managed by the ANR Associate Editor
for Agricultural Pest Management.
The UC IPM Pest Management Guidelines are available from:
• Online: http://ipm.ucdavis.edu
• UC Cooperative Extension County Offices
• University of California
ANR Communication Services
Richmond, CA 94804
510-665-2195; 800-994-8849
Updates: These guidelines are updated regularly. Check with your University of California Cooperative Extension Office or the UC IPM
website for information on updates.
Note to readers: These guidelines are for field production and not greenhouse. They represent the best information currently available to the
authors and are intended to help you make the best choices for an IPM program. Not all formulations or registered pesticides are mentioned.
Always check the label and with local authorities for the most up-to-date information regarding registration and restrictions on pesticide use.
Check with your agricultural commissioner for the latest restricted entry intervals.
UC IPM Pest Management Guidelines - CUCURBITS
(10/11) Cucurbits Year-Round IPM Program Annual Checklist iv
Download this checklist at http://ipm.ucdavis.edu/FORMS/
http://ipm.ucdavis.edu
Cucurbits Year-Round IPM Program
(Reviewed 10/11)
ANNUAL CHECKLIST
Supplement to UC IPM Pest Management Guidelines
These practices are recommended for a monitoring-based IPM program that enhances pest control and reduces
environmental quality problems related to pesticide use.
Water quality becomes impaired when pesticides and sediments move off-site and into water. Air quality becomes
impaired when volatile organic compounds (VOCs) move into the atmosphere. Each time a pesticide application is
considered, review the Pesticide Application Checklist at the bottom of this page for information on how to minimize
water and air quality problems.
This year-round IPM program covers the major pests of cucurbits in the Sacramento, San Joaquin, Coachella, Palos
Verde and Imperial valleys, as well as Riverside County. Details on carrying out each practice, example monitoring
forms, and information on additional pests can be found in the Cucurbit Pest Management Guidelines (PMG) at
http://ipm.ucdavis.edu/PMG. Track your progress through the year with the annual checklist form.
ü Done Preplant
Special issues of concern related to environmental quality: runoff, drift, volatile organic compounds
(VOCs).
Mitigate pesticide usage to minimize air and water contamination.
Select the field:
• Consider soil type, cropping and pest history, and plantback restrictions from the previous crop
• Consider crop rotation for fields with high populations of problematic weeds and difficult
pathogens/diseases such as:
o Fusarium crown and foot rot
o Fusarium wilt (cantaloupe)
o Fusarium wilt (watermelon)
o Vine disease decline
o Vine disease decline (Monosporascus cannonballus)
o Root knot nematodes
Take a soil sample for:
• Nutrient, salinity, and pH analysis to determine field suitability and soil nutrient management.
Manage salty soils to reduce risk of charcoal rot.
• Root knot nematode if there is a history of galls on roots of previous crops. If soil sampling
indicates the presence of root knot nematodes, the soil should be treated according to the PMG.
Clean equipment and tractors between fields to prevent the spread of some soilborne pathogens and
weed seeds.
Identify a planting date that permits harvesting before frost. Consider the following:
• If planting into cover crops or no-till fields with heavy residue, additional germination time may be
required, as these soils tend to be cooler.
• Early-planted melons often avoid competition from barnyardgrass. Late plantings in the San
Joaquin Valley for fall harvest and fall-planted melons in desert areas have higher insect and
disease pressure, especially viruses.
UC IPM Pest Management Guidelines - CUCURBITS
(10/11) Cucurbits Year-Round IPM Program Annual Checklist v
Download this checklist at http://ipm.ucdavis.edu/FORMS/ Download this checklist at http://ipm.ucdavis.edu/FORMS/
ü Done Preplant
Special issues of concern related to environmental quality: runoff, drift, volatile organic compounds
(VOCs).
Mitigate pesticide usage to minimize air and water contamination.
Prepare the field in the fall if a spring planting is planned.
• Cultivate crop residues.
• Manage weeds.
o Preirrigate the field to germinate weed seeds and cultivate, or apply an herbicide, or in special
situations, a soil fumigant according to the Cucurbits Pest Management Guidelines.
o Consider a fallow bed herbicide treatment on pre-formed beds to prevent winter weed growth and
allow early spring melon planting.
o If planting into a cover crop or utilizing conservation tillage or no-till systems, apply a burn-down
herbicide prior to planting and before cover crop reaches 1 ft. tall.
• If using soil fumigants, for weeds or other pests, check the label for details on the minimum time
required between application and planting to prevent crop damage.
• Apply fertilizer, lime, gypsum, or other soil amendments based on soil test results.
• Most cucurbits grow best at soil pH of 6.0 to 7.0.
o If liming is required, applications should be made well in advance of planting to give soil acidity time to
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