ISSUE #461 2004 Challenges Raise Many Questions

461 2004 Challenges Raise Many Questions


Q1. What caused crop yield and quality that was well below average in mid-September to finally achieve long term averages?

A1. The single factor having the greatest impact on crop growth was lack of adequate growing degree days through mid September. Late September rains and warm dry conditions in the first week to 10 days of October resulted in dramatic improvement in yield and quality.

GDD from April 1 to September 30 in 2004 Versus 2003

YearCavalierGrand ForksFargo
2003 4,674 4,816 5,135
2004 3,987 4,221 4,558
Difference 15% 12% 11%

Q2. Why was sugar content low, at some stations especially in Polk, Norman and Clay counties?

A2. Growing degrees were low with tonnage, growth and sugar content increases delayed throughout the season. Predominantly wet and cloudy weather, with above average rainfall minimized sugar content increases, especially in September. Increased incidence of Rhizomania and Fusarium may also have been a factor in an area from Crookston to Moorhead.

Q3. How could crop sugar percent be only average with such excellent SLM values?

A3. Reasons for this observation might include 1) excellent N management by growers, 2) much less than normal mineralization release of N, 3) reduced senescence of crop canopy in late summer, and 4) an increased percent of the crop with zone N management.

Q4. Why did the crop appear to yellow off early in some growing areas?

A4. Minor early yellowing occurred in some areas of the Red River Valley that were quite dry. However many fields were greener than desirable in late August and September indicating no lack of available N. Rhizomania and Fusarium severity caused significant yellowing in some fields in Clay, Norman, Polk, Grand Forks, and northern Traill counties.

Q5. How did the incidence and severity of Rhizomania change in 2004?

A5. Rhizomania continues to spread into areas where it has not previously been a problem. Severity of Rhizomania has noticeably increased in areas where the disease has been a problem for several years? Resistant varieties should be considered in Polk, Norman and Clay counties along with selected other areas in many counties.

Q6. Rhizomania might be present but only caused minor yield losses in many areas?

A6. It's true that impact may have been minor in some areas, but yield and quality may have been even better if resistant varieties were planted where needed. Yield losses in Rhizomania strip trials were about 40% with susceptible varieties at Crookston and at a site northeast of Moorhead.

Q7. Why was weed control generally excellent in 2004, especially for Kochia?

A7. Kochia control was greatly improved due to much greater use of Nortron, Ethotron and Etho SC in 2004. Timely use of post emergence sprays and soil applied products controlled weeds very well even on heavy infestation fields. Initial use of GDD information to time herbicide application also proved successful. A grower focus on Kochia control in rotational crops has been beneficial.

Q8. Why was root maggot damage more severe than expected?

A8. Several possible reasons include 1) a very long time from initial at plant application of insecticide until much delayed maggot pressure with low residual insecticide activity remaining 2) presence of small beets, because of low GDD, at time of fly emergence resulted in more injury 3) a long period of fly emergence attacking small plants 4) heavy rains before fly emergence probably reduced at-plant insecticide activity.

Q9. What conditions other than lack of GDD contributed to slow germination and emergence last spring?

A9. Excessive spring tillage especially with equipment that did not repack the seedbed resulted in seeds setting in dry soil and severe soil erosion. In other cases excessive crop residues left on the soil surface reduced seed to soil contact in dry areas and in wet areas kept seedbeds cold and unfavorable for stand establishment.

Q10. Were any new threats to RRV sugarbeet production identified in 2004?

A10. Fusarium a root disease has been present in the RRV for at least 10 years. Fusarium root rot was identified in far more areas of the RRV in 2004. Significant yield loss occurred in a number of Moorhead fields and isolated parts of fields in other factory districts this year. Resistant variety use is the only control measure available.

Q11. Did growers lose money applying fungicides in 2004 for Cercospora control?

A11. That's a very difficult question to answer. It's possible some fields were sprayed more than necessary. However, fields that were sprayed more often had a much healthier canopy at the start of full stockpile and buffered frost on the first day of harvest. The healthy canopy undoubtedly contributed to sugar and yield gains in October. This improved canopy growth benefit is being evaluated by Dr. Larry Smith. Watch for research reports this winter.

Q12. Is there any reason a grower should delay ordering beet seed for 2005?

A12. Growers should certainly consider ordering some seed of the "hot" new varieties early on. However highly informed decisions include a review of three years of coded trial data 2002-2004. A look at grower practices data summaries, appropriate strip trial data, and performance on your farm.

Diseases and Variety Selection

If in doubt about severity of Aphanomyces, Rhizomania and Fusarium in your area, contact your agriculturist for assistance. The Ag staff can help make that critical on-farm profit decision regarding resistant variety use for the 2005 season.

NDSU Survey Responses Needed

Growers are strongly encouraged to complete the NDSU Production Practice Survey and return it to Dr. Alan Dexter ASAP. The survey can be completed in the shareholder access area of this web site.