The USA Sunflower Survey is coordinated by Max Dietrich, National Sunflower Association, 4023 State St., Bismarck, ND 58501-0690

Art Lamey, NDSU Extension Plant Pathologist, Emeritus, assembles the data for the survey from each state.

John Nowatzki, NDSU Extension Geospatial Specialist, prepares GIS spatial maps for the survey and serves the information on the Internet.

Survey Methods (complete paper with results in .pdf format)

A field survey in eight sunflower-producing states was conducted in August and September 2002. It was similar to a 2001 survey in North Dakota and South Dakota. Both surveys estimated yield and plant population and determined class (oil or confection), use of certain cultural practices, weed intensity, insect damage, bird damage, lodging, and disease infection. In addition, seeds from each field surveyed were sampled for subsequent laboratory determination of insect damage to the seed.

Materials and Methods. One field was surveyed for every 5,000 acres in each state and county, based on the planted areas in 2001. Survey teams of three or four persons were organized for each state and training was provided at the beginning of the survey. During the training each team member received a 3-ring notebook containing illustrations of weeds, insects and diseases, several assessment keys, instructions on estimating yield and plant population, three data recording forms and a master summary sheet. Each team had a specific area to survey, and a specific number of fields to survey. The location of each field surveyed was to be determined using a hand-held GPS unit. However, since not all teams had GPS units, some teams recorded the mileage and direction from nearby towns. Two teams surveyed 19 fields in Colorado, 6 teams surveyed 31 fields in Kansas, 1 team surveyed 6 fields in Minnesota, 1 team surveyed 1 field in Missouri, 21 teams surveyed 265 fields in North Dakota, 1 team surveyed 12 fields in Nebraska, 13 teams surveyed 131 fields in South Dakota and 1 team surveyed 12 fields in Texas. Survey dates in the high plains were Sept. 9-13. South Dakota survey dates were Sept. 16-17. Survey dates in Eastern North Dakota and Minnesota were Sept. 18-19 and in western North Dakota they were Sept. 25-26.

Yield was estimated by determining plant population, head diameter, seed size, percent good seed and center seed set for two 25 foot measured rows (or two 5 X 25 foot measured areas in solid-seeded fields). The areas used for yield estimations were selected as typical of the field. The class of sunflower was recorded, row spacing was recorded as greater or lesser than 20 inches and the tillage was listed as no till, minimum till or conventional till. No till was defined to have no soil disturbance, and minimum till to have only slight soil disturbance. Data on plant population and estimated yield calculations were entered on a data recording form that also listed 29 common weeds and their prevalence, and the major yield limiting factor for each field.

The 29 common weeds evaluated were annual smartweed, biennial wormwood, Canada thistle, cocklebur, common lambsquarters, devil's claw, kochia, lanceleaf sage, marshelder, nightshade, Palmer amaranth, puncturevine, redroot pigweed, Russian thistle, common ragweed, giant ragweed, water hemp, wild buckwheat, wild mustard, wild sunflower, wollyleaf bursage, barnyardgrass, downy brome, field sandbur, green foxtail, yellow foxtail, quackgrass, volunteer grain, and wild oats. Weeds were assessed as 0, none; 1, light (scattered, up to 1 plant per 3 ft of 30 inch row); 2, moderate (1 plant per 1 ft of 30 inch row or 3 plants for grassy weeds); and 3, heavy (more than 1 plant per 1 ft of 30 inch row or over 3 for grassy weeds). Data was entered on the same data recording form used to record plant population, yield, and the major yield-limiting factor. The weed data is published as a separate report.

Diseases surveyed included Sclerotinia (wilt, head rot, mid stalk rot), Phomopsis, Rhizopus head rot, downy mildew, red rust, white rust, charcoal rot, and Verticillium. Rust was determined for severity (percent leaf area infected) using rust assessment illustrations. All other diseases were evaluated for incidence (percent infected plants). Data on lodging also was assessed. Fifty plants in three groups of 17, 17 and 16 plants were examined to make disease and lodging assessments. Data was entered on a data recording form for disease and lodging. This data is published as a separate report.

Midge and bird damage each was assessed using separate sets of damage assessment illustrations. Assessments were made for the field edge and also for the interior of each field. Data also was recorded on percent of heads with webbing and on percent of plants infested with the spotted sunflower stem weevil and the long-horned beetle. Seed samples from the edge of the field and the interior were taken for analysis in the USDA sunflower insect laboratory in Fargo, ND to determine insect injury from seed weevil, banded sunflower moth, sunflower moth, and brown spot (confection only). All field data was entered on a data recording form for bird and insect damage. This data is published as a separate report.

One person on each team served as recorder. That person copied the data from the three data recording forms to a master summary sheet containing all data from each field. This master summary sheet was later used for data entry onto a data spreadsheet for each team. Data from each team was transmitted electronically to Max Dietrich at the National Sunflower Association, to the USDA sunflower insect laboratory and to Art Lamey to develop master spreadsheets for each state and for the entire survey. Each state's spreadsheet was transmitted to John Nowatzki, North Dakota State University, for construction of GIS maps