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2013 NSA Crop Survey Report
Monday, January 6, 2014
filed under: Research and Development
For the last 12 years (except 2004), the National Sunflower Association has conducted in-depth fall surveys in producers’ fields throughout the main sunflower growing regions of the United States as well as the Canadian province of Manitoba.
During the 2013 sunflower growing season, 32 trained teams — including agronomists, entomologists, pathologists, crop consultants and/or producers — randomly stopped at 209 sunflower production fields, which represent approximately one field for every 10,000-15,000 acres in sunflower-producing counties. Each team evaluated plant stand, yield potential, disease, insect and weed issues for each field. They also assessed bird damage and agronomic practices used in the field.
A seed sample was taken from each field to detect insect damage in the laboratory. A yield estimate was calculated based on plant stand, head size, seed size, seeds per head and percent loss due to bird feeding. The 2013 average surveyed sunflower yield was 1,733 lbs/ac, with an average per-acre plant population of 15,977.
Determination of yield-limiting factors was based on the surveyors’ judgment after considering all production aspects in the field. The limiting factors may be different in the various states. For instance, drought may have been less severe in some parts of North Dakota, Manitoba and Minnesota compared with southern states. The results of the survey do not include events taking place after the survey. For instance an early season snowstorm caused lodging of sunflower plants in North and South Dakota. However, the event took place after the survey was conducted; therefore, wind damage is not included in the results presented here.
Overall, the most limiting factor in 2013 was plant spacing within the row, followed by plant disease, drought and lodging. The plant spacing difficulties consist of large skips within the row or areas where plants grow too close together, causing one of the plants not to contribute to the sunflower yield. Equal distribution of plants is essential to obtaining maximum sunflower seed yield.
Irregular plant spacing in the row may have been caused by poor seeding conditions, failure to adjust the planter, driving too fast, poor germination, disease, insect damage or other factors. The average yield of 54 fields with plant distribution issues was 1,844 lbs/ac, compared with 22 fields with no observed problems yielding 2,070 lbs/ac. Producers should pay attention to their management and refine their technique while seeding sunflower. Planter calibration may be the first step to reducing skips and achieving better plant spacing within the row.
The average yield in the fields with drought as a limiting factor was 1,324 lbs/ac, which is 64% of the yield obtained in fields without production issues.
In 2013, “no limiting factor” could be determined in 11% of the fields, while in 40% of the fields “no problem” was reported for the second limiting factor. The “no problem” category indicates that the evaluators felt the field reached its maximum yield potential for the 2013 growing season. Across the last three seasons, surveyors did not find a second most yield limiting factor in about 35% of the fields.
The diseases of most concern in sunflower are leaf rust, Sclerotinia and Phomopsis. In 2013 sunflower leaf rust incidence (percent of fields in which rust was found) was higher in Kansas, Nebraska, Colorado, Texas and North and South Dakota compared with 2012. Rust was found in 65% of all fields surveyed, compared to 38% in 2012.
Sclerotinia head rot (percentage of plants) in fields with the disease was up in Minnesota and South Dakota but down in North Dakota, Manitoba and Vermont. (Head rot was not diagnosed in the surveyed southern states.) Phomopsis severity was in general higher in 2013 compared with 2012.
Dectes long-horned beetle was found in 100, 33, 49 and 34% of the fields in Kansas, Colorado, South Dakota, and North Dakota, respectively. The percent of plants with Dectes was 66, 56, 35 and 42 in Kansas, Colorado, South Dakota and North Dakota, respectively. Thirty three percent of all fields surveyed had Dectes present with on average 42% of the plants showing Dectes activity.
Seed weevil damage was found in 47% of the sunflower samples submitted to the USDA-ARS laboratory in Fargo, N.D. Of those samples with seed damage, the average number of seeds with seed weevil activity was 5.2% (compared to 2.8% in 2012).
Bird damage was reported in 75% of the surveyed sunflower fields in Vermont, 51% in North Dakota, 43% in Manitoba and 16% in Nebraska. The average damage per head across all the surveyed fields was 8.9%. (Note: As the survey was taking place a few weeks before harvest, it is very likely that actual bird damage numbers at harvest were higher.)
Broadleaf weeds continue to be more of a problem in sunflower fields than most grassy weed species. Palmer amaranth is a major problem weed in Kansas and was recorded as being present in 100% of the surveyed fields. In Texas, 75% of the fields contained Palmer amaranth. In fields were surveyors mentioned weeds as the most limiting factor, the average yield was 1,776 lbs/ac, which is about 86% of the yield from the fields with no yield limiting factor reported.
The data generated in the National Sunflower Survey can be used by producers to make better management decisions. The information is also providing trends over time. The survey data will be used to help define research priorities, improving sunflower crop production and the bottom line for producers.
Full 2013 survey results are online at: www.sunflowernsa.com/growers.