Graphite or Talc?
Thursday, April 15, 2004
filed under: Hybrid Selection/Planting
Funny thing how the best source of planting information on your farm sometimes doesn’t get read as well as it should.
Yes, we’re talking about the operator’s manual for your planter.
Calibration, servicing, settings, depth control, optimum planting speed, troubleshooting – if your manual is like most others, all that information and more is in there.
More treated sunflower seed will be planted this year, with the addition of Cruiser as a seed treatment option for early-season insect control. Thus, take note on whether your operator’s manual specifies to use a lubricant with treated seed, and if so, whether it should be graphite or talc.
Generally, talc is used in vacuum and air planters, and graphite in finger pick-up planters. Check your manual to know for sure. If the manual calls for a seed lubricant, be sure to use it, and at the specified rate, since it can make a difference in getting optimal seed drop. And again, use the right seed lubricant, talc or graphite, as they are not interchangeable.
Here are partial recommendations on the use of a talc lubricant from the operator’s manual of a vacuum planter:
“Some commercially-applied seed treatments or farmer-applied seed treatments may cause a deterioration in seed singling, spacing accuracy, and seed flow into the vacuum seed meter. To minimize these adverse effects, (planter manufacturer brand) talc lubricant should be used whenever treated seed is being used. Avoid using a graphite based treatment or graphite treated seed.”
Note that the instructions specifically point out not to use graphite in the vacuum planter. The manual also pointed out that it’s important to apply the seed treatment to the seed before applying the seed lubricant, to ensure that the treatment adheres to the seed properly while minimizing buildup on meter components.
A few more planting tips to keep in mind, before you dig for that operator’s manual:
It’s important to know a field’s herbicide use history and to always check herbicide labels regarding rotational restrictions.
Sunflower seeds have more variation than most other seeds. That’s why it’s important to clean and adjust your planter before planting ‘flowers. Use the recommended plates, fingers and air pressure to help avoid skips and doubles.
Soil temperature needs to be at 50° or more at seed depth (1.5 to 2.5 inches). Planting sunflower seed into cold soils may cause seed to go into dormancy and can delay germination.
Run your planter at recommended speeds. Going too fast will mean inconsistent seed placement and uneven emergence. Proper air/vacuum pressure and properly calibrated seed meters will lessen the impact of increased planter speed. However, as speed increases so does vibration. The greater the vibration, the more times the seed bounces from side-to-side in the delivery tube before reaching its place in the seed furrow.
Sunflower seed needs to be planted at depth of 1.5 to 2.5 inches. Percent emergence will decrease as planting depth increases, especially for smaller seed sizes.
If heavy rain forms a soil crust, deep-seeded plants will have a particularly difficult time breaking through. Harrowing the crust before the emerging seedlings reach to within one half inch of the soil surface will improve emergence.
Sunflower needs to have excellent seed to soil contact. Because sunflowers have a woody hull, closure of the furrow becomes more important than for corn and most other crops.
– Tracy Sayler
Sunflower Planting Dates
North Dakota State University sunflower planting date studies at Carrington and Langdon indicate oil percent is highest in early planted (May 10-20) sunflower. Test weight is also higher when planted early. Seed yield at Carrington was highest when planted May 20-30. Earlier planting (May 15) usually allows for earlier maturity and (hopefully) warmer harvest weather.
The optimal window for planting sunflower in southwest North Dakota appears to be May 20-24, according to results of a planting study conducted by the North Dakota State University Research Extension Center, Dickinson, N.D.
General recommendations for sunflower planting in South Dakota is mid May to early June. South Dakota State University research indicates that oil is generally more affected by late planting than yield. Oil content generally begins to decline in sunflower planted after June 15, and yield generally begins to drop in sunflower planted late June.
Sunflower can be planted in Kansas from early May to late June, according to the Kansas State University Extension Service, although some growers in the High Plains have even planted sunflower in early July and produced a successful crop. Early plantings generally result in larger seed size and higher oil, but may encounter more insect problems, and may require treatment. Conversely, later plantings are prone to smaller seed and lower oil, but may experience fewer insect problems.
Plant early maturing hybrids when planting sunflower late or replanting.