ISSUE 15 August 11, 2005
Flax acreage continued to increase in North Dakota, with over 800,000 acres expected to be harvested in 2005. A number of new producers have called requesting the proper time to cut and harvest flax.
Flax is ripe when 90% or more of the bolls have turned brown and can be combined direct. Any green bolls remaining will crush and pass right through the combine. Direct combining is the efficient method and is entirely satisfactory when the flax is thoroughly dry and free of weeds. However, the most common method of harvest is with the swather and windrow pickup attachment on a combine because few fields are free of weeds and few ripen uniformly. Flax is considered to be fully mature when 85% of the bolls have turned brown. After this stage has been reached, the crop may be swathed. If regrowth occurs in the fall, cut the crop when the greatest amount of ripe seed can be obtained. Do not delay the harvest too long because fall rains may cause weathering of the mature seed and frost may cause immature seed to turn black, resulting in a reduction in grade. Swathed flax is in condition to combine after a few days of dry weather. Swath rollers are often used to pack the windrow to prevent destruction or movement by wind. When swathing, leave a stubble height of about 5 to 6 inches to hold the flax swath off the ground for good air movement and drying.
Considerable frost damage occurs in immature seeds when temperatures drop to the 27 to 23E F range, while leaves are severely damaged at 25 to 23E F and stems are killed at 21 to 19E F. Cutting or desiccating flax at an immature stage is not known to result in seed blackening, but yields will be reduced due to early termination of seed development. This will result in thin seeds of lower test weight.
Chemical desiccation may be used to accelerate drying of the crop and any weeds that may be present. It does not speed crop maturity, but will reduce the time from maturity to harvest.
Potential advantages from this practice are:
A desiccant such as Defol may be applied after 80% of the bolls have turned brown.
In North Dakota, Defol (sodium chlorate) and glyphosate (various brands) can both be used for weed desiccation. When using glyphosate, the seed moisture must be 30% or less and allow for a 7 day preharvest interval. Do not apply glyphosate to flax grown for seed purposes because seed germination and vigor may be reduced.
Studies at Morden, Manitoba by Ag Canada researchers have shown that yields are reduced if applications are made too early. For instance, swathing or desiccating at the 25 to 50% brown boll stages, reduced yields by an average of about 10% and 5% respectively, due to premature termination of development of some of the seed.
Desiccated flax should be harvested as soon as possible after it is ready, to avoid boll loss and weathering of the seed.
Flax should be stored at 10 percent moisture or less for safe storage. For long-term storage, 8 percent moisture is suggested.
2005 SOYBEAN PLOT TOURS
An open invitation is extended to soybean producers, their family, and friends to attend the annual soybean plot tours and suppers scheduled for September 1, 7 & 8th. The events are free of charge and sponsored by the North Dakota Soybean Council, the ND Soybean Growers Association, and Agri Business leaders in the area.
The evenings will commence with field plot tours followed by research updates on the latest developments for the future of the soybean industry. The Council has invested check-off dollars in a series of promising research endeavors from production issues to industrial uses.
The plot tours are scheduled to begin at the following locations and times given below:
Thursday, Sept. 1st -4:30 pm - Jeff and Maxine Leinen Farm (½ mile west of Great Bend, ND just off I_94).
Wednesday, September 7th- 4:30 pm- Vanessa and Paul Kummer Farm (Plot site is 3 miles west and 2 miles south of Colfax, ND.).
Thursday, September 8th - 4:30 pm - Greg and Deb Gebeke Farm (Hwy 18 north of Casselton, to County Road 34, west on County Road 34 for 2 miles, then north on gravel road 1.2 miles).
Following the research portion and viewing of soybean trials, all participants are invited to enjoy cold beverages and an evening meal.
Source: North Dakota Soybean Council and ND Soybean Growers Association
Duane R. Berglund
NDSU Extension Agronomist
SELECTING WINTER WHEAT VARIETIES
The optimum planting date for winter wheat is now only about a month away and it is time to select the variety or varieties that you will plant this fall. Carefully consider the following when selecting winter wheat varieties:
Winter-hardiness - Perhaps the single most important trait that imparts yield stability in a winter wheat variety in North Dakota is winter-hardiness. Winter-hardiness is the term used to describe how a variety survives sub-freezing temperatures. Varieties that are rated as the most winter-hardy, in addition to being able to survive the extreme cold of winter, are also generally able to tolerate sub-freezing temperatures in the spring. Low spring temperatures, in fact, usually cause more damage to winter wheat than the extremely cold temperatures during the winter. Varieties that were developed for Canada (i.e. CDC Falcon and CDC Buteo) and North Dakota (Jerry, Ransom, Roughrider, etc.) tend to be the most winter-hardy, while those developed for Nebraska or other more southern states (i.e. Wesley, Millennium, Jagalene, etc.) tend to be the least winter hardy. Varieties developed for South Dakota and Montana tend to be intermediate in their winter-hardiness response. For ratings on winter survival of varieties recently tested in North Dakota see:
If you are planting into bare ground or ground with little residue (i.e. soybean residue) this fall, use only the most winter hardy varieties to reduce the risk of winter kill.
Yield - The yield of a variety is dependant on many factors such as how well it survives the winter, its genetic yield potential, the amount of disease and insect damage it sustains and how it responds to environmental stresses and management practices. Select varieties that performed well in replicated tests over a range of environments, not just those that did well in a single location and year. Give extra weight to varieties that yielded well in years that had a high level of winter kill in order to reduce risk. To review the 2004 winter wheat varietal trial results go to: http://www.ext.nodak.edu/extpubs/plantsci/smgrains/a1196w.htm Variety trial results for 2005 will be added to the ND Small Grains Page when they become available (http://www.ag.ndsu.nodak.edu/aginfo/smgrains/).
Plant Height - Many growers prefer shorter varieties as they tend to lodge less and produce less residue. Excessive residue is considered undesirable in many zero-till systems. Wesley, Wendy (a new white wheat from SD), Expedition, Jagalene, and CDC Falcon are the shortest of the varieties considered adapted to ND. Of this group, CDC Falcon is the most winter hardy.
Disease Resistance - In the past, little importance was given to disease resistance in winter wheat because it often matures before disease epidemics become too damaging. In 2005, however, disease resistance became a dominant factor in the yield of winter wheat varieties. Based on preliminary data from one site in Ransom county, the following varieties were found to be the most resistant to foliar diseases (rust and Septoria leaf spot): Harding, CDC Buteo, Millennium and McClintock. For Fusarium head blight (scab), Roughrider, Jerry, Ransom and Harding were the most resistant and Jagalene, CDC Falcon, Wesley and Wendy the most susceptible. Shorter varieities tend to be more susceptible as the heads are closer to the source of inoculum. Similar rankings by varieties for scab severity in Ellendale were also reported in a previous Crop and Pest Report, though fewer varieties were included, see the following website: http://www.ag.ndsu.nodak.edu/aginfo/entomology/ndsucpr/Years/2005/july/13/ppath_13july05.htm#WINTER)
PLANTING RECOMMENDATIONS FOR WINTER WHEAT
Winter wheat should be planted into standing stubble of sufficient height to hold at least 6 inches of snow in order to reduce the risk of winter injury. The optimum planting period for winter wheat is between September 10-30 for southern regions of the state (south of Highway 200) and September 1-15 for northern regions. Green plants (i.e. small grain volunteers) in fields to be planted to winter wheat should be killed at least 2 weeks prior to planting in order to reduce the risk of wheat streak mosaic virus, a destructive disease of winter wheat that is vectored by a mite.