I had a number farmers reporting diseased wheat in fields at harvest time. Specifically, darker colored wheat plants and empty wheat heads. These symptoms may be mistakenly identified as loose smut, seed borne disease – which is controlled during wheat seed certification process, and with fungicide seed treatments. If this is your common management practice, probability of having loose smut is 99.99%! I would not neglect possibility of this disease in your field if you planted bin-run seed that was not treated.
This is more likely TAKE ALL disease that was pretty common this year due to wet spring. If you try to dig the pant out, it would have damaged or no roots and lover stem will be dark in color (see 3rd picture below). It showed on both certified and bin-run seed in our plots at Stumpf Wheat Center near road ditch that had standing water for 2 days in spring. Plots were planted behind fallow with wheat stubble in it.
Disease is residue-borne more likely to be present in wheat-fallow rotations, and wet areas of the field (low drainage, compaction, heavy-textured soils). Wheat dies prematurely, so it appears white during grain fill period (instead of being green) and back at harvest (instead of being yellow/gold). Pathogen also survives on downy brome and other grassy weeds that may be in in ditches. Disease has potential to wipe out the whole field.
For management do rotate your wheat with corn, sorghum, peas, etc., give residue time to break down, and control grassy weeds!
Glad to see a lot of good wheat around! Not so glad to see discounts at the elevator! Learn to live by faith or die!
In past two weeks, SW Nebraska received about 1 inch of precipitation, average air temperatures raged between 45 F and 65 F generating 123 GDD (growing degree days), soil temperatures had a gradual increase from 50 F and currently are at 58-62 F.
Corn planting and emergence progress
Most of the farmers are finishing up corn planting. There is about 20% corn acres yet to be planted and roughly 20% already emerged. Early planted corn emerged well despite the low soil temperatures. Strips that were tilled for corn to be planted consistently had higher reading then data from the weather stations, thus no injury occurred in most places. Corn plants, however, do look pale and yellow in color due to lack of sunshine and temperatures, but will grow out of it with warmer weather to come (Picture 1). To asses corn replant options due to poor emergence click here.
Wheat is generally in good conditions and is pushing flag leaf. There are reports of isolated stripe rust infections in SW Nebraska and preventive areal fungicide applications started this week (Picture 2). Applications prior to flag leaf emergence are not advised. If farmer has a stripe rust resistant variety, regular scouting and prolonging fungicide application by 10 days or so may provide long enough residual activity of fungicide to protect the flag leaf and avoid second fungicide application later on in the season.
Picture 2. Preventive areal fungicide application in wheat
Wheat is showing signs of nitrogen deficiency. Yellowing of the leaves is common in low areas of the fields with standing water and poor drainage conditions. In addition, sporadic yellow spots may be found throughout the field due to nitrogen that has been leached bellow the root zone (Picture 3).
Field peas are relatively new crop in western Nebraska with promising agronomic potential and growing national and international markets. UNL Extension partnered with 5 farmers to receive USDA SARE (Sustainable Agriculture and Research Education) grant and investigate agronomic issues related to field pes production in SW Nebraska. Weed control is one of those issues and it will be interesting to see how well field peas compete against kochia (Picture 3). Field peas are at 3-5 leaf stages. For more information on field peas click here.
Winter wheat is currently in pretty good condition mostly due to good moisture at planting and favorable temperatures for plants to winter harden (vernalize) before cold temperature set last fall. Yet, many farmers have been concerned about higher then normal temperatures during February and wondering how this might affect winter kill in wheat.
Wheat does loose winter hardiness every time warm temperatures break its dormancy, and so it is important to become familiar with wheat sensitivity to cold temperatures at different growth stages.
During tillering stage, growing point of wheat is near the soil surface and well protected from frizzing injury. Plants might show damage in form of leaf twisting and discoloration, or even loosing tillers, but plant will be able to come back from the secondary tillers and produce good yield.
This years’ sufficient soil moisture helps reducing potential freezing injuries on crown and roots that might come from temperature fluctuations, as moist soil warms up and cools down about six times slower then dry soils.
In the jointing stage, when wheat starts to move the head up the stem, growing point is above the soil surface and more susceptible to injuries that might come from freezing or hail injury. According to K-state research, wheat will still be able to tolerate temperatures in the mid to upper 20’s without causing significant yield losses.
Farmers in this region frequently tell me: “Wheat dies 9 times before you get any grain out of it.” Therefore, fallow these wise words and if you suspect winterkill try not to make any quick decisions. Wait for several days of warm temperatures, give plants an opportunity to recover, and conduct careful assessment crop condition and its yield potential before you decide to tear out a field.
Below is a snapshot of 4 Educational opportunities in SW Nebraska. For more information contact Strahinja Stepanovic, email: firstname.lastname@example.org, phone: 402-318-1124
1. WC Cattleman’s Day
Joint Program of NE Extension and CSU Extension developed for cow/calf producers. This conference should help you find ways to reduce cost while helping to improve your overall profitability. Speakers and Topics:
Robert Tigner, NE Extension Educator – Managing Replacements to Maximize Heifer Values. Can You Afford to Re-build your Herd?
Randy Sander, NE Extension Educator – Increasing Reproductive Efficiency of the Cow Herd
Chris Shelly, CSU Livestock Agent – From Mineral Supplementation to Cattle Transportation
Troy Waltz, NE Extension Educator – Grazing System Management and Using Annual Forages
Strahinja Stepanovic, NE Extension Educator – Forage kochia
Registration: $20 at the door, $15 if preregistered by Jan 28
Refreshments: supper included
5:00-8:00 pm MT
Cross Roads Wesleyan Church
1710 Wesley Drive, Imperial, NE
2. On-farm Research Update
Find out results of 16 on-farm research studies conducted in SW Nebraska addressing issues such as growing field peas, fertility management in high ph soil, soybean row spacing, and testing growth enhancement products. Learn about projects from other parts of the state on topic such as: variable rate seeding, planting populations, Maize-N nitrogen rate decision tool for sidedress nitrogen, starter fertilizer, fungicide applications, row spacing, cover crops, foliar micronutrients, seed treatments, and others.
Registration: not required.
Refreshments: lunch included
12:00-4:30 pm CT
West Central Research and Extension Center (WCREC)
402 W State Farm Rd, North Platte, NE
3. Irrigation scheduling tools and maximizing irrigation performance
Learn essentials on maximizing irrigation performance and utilizing various tools for irrigation scheduling such as evapotranspiration (ET) gauge and soil moisture sensors. You will also receive an update on our Extension programs that address water issues and have the opportunity to participate in them (we will give you ET gauges to try them out) so we can together contribute to the wellbeing of our community. Speakers:
Strahinja Stepanovic, NE Extension Educator
Chuck Burr, NE Extension Educator
Dr. Daran Rudnik – UNL Irrigation Specialist
Registration: not required
9:00-11:00 am MT
Stumpf Wheat Center
76025 Road 329, Grant, NE
1:30-3:30 pm MT
Chase County Extension Office
135 W 5th street, Imperial, NE
5:00-7:00 pm MT
Dundy County Courtroom
112 W 7th Ave, Benkelman, NE
4. Weeds, Insect and Disease Resistance Workshop
Unique opportunity to learn from University specialists and local crop consultants from our region about the importance of herbicide, insecticide and fungicide resistance management, mode of action, and how to use this information to reduce spread of weeds, insects and plant pathogens in Nebraska. Speakers and topics:
It has been three weeks since we had our last rain in SW Nebraska and we are seeing all dryland crops showing signs of drought. Reference evapotranspiration (ET) in the Upper Republican NRD ranged from 1.6 inches in Perkins Co to 2.9 inches in SW Dundy Co. This means that crops in SW Dundy Co used about 1.5 inches of water more than in Perkins Co. See image for more details on ET and rain data as well as crop growth stages and their water use coefficients for this period.
According to US Drought monitor none of the Counties in SW Nebraska are in abnormal drought, which can means that these conditions are (believe it or not) normal in SW Nebraska this time of the year. According to 30-year weather data, average August precipitation and ET are 2.50 and 9 inches, respectively. This means that the area had the August weather conditions in very close proximity to long term average.
We had very good growing conditions in May, June, July and August, so crops used all that water and heat to produce large biomass and increase yield potential. Rain is much needed to keep up with high water demands during the grain filling period in September, otherwise we will have to be satisfied with the mediocre dryland yields at the end of the year.
Reference evapotranspiration (ET) and rain in the Upper Republican NRD was around 1.3 and 0.05 inches, respectively. See attached image for more details on ET and rain data as well as crop growth stages and their water use coefficients for this period.
Dryland crops in SW Nebraska are showing signs of drought, but are generally in good conditions. My rough estimation on average dryland corn yield this year would be around 110 bu/ac. Irrigated corn and soybean look very good! Relatively lower ET allowed irrigators to catch up with crop water demand. A number of corn fields have high infestations of western bean cutworm with larvae already feeding on ears. Insecticide treatments are not advisable at this point since pest is well protected. If corn is to be planted next year consider Bt-trait that will control (or suppress it) or plan on insecticide application during the season. Western corn rootworm beetles are flying and insecticide application may be applied to prevent battles from laying eggs and reduce next year’s larvae damage. If corn is rotated with some other crop insecticide application is not recommended at this point.
Management checklist for wheat producers:
1. Control volunteer wheat and weeds in wheat stubble and fallow to preserve moisture and nutrients, reduce the weed seed bank and control disease vectors.
Research from USDA‐ARS, Central Great Plains Research Station in Akron indicates 4-6 bu/ac yield penalty on wheat for each inch of available soil water being reduced at wheat planting.
Nutrients taken up by weeds and volunteer wheat can increase the cost of your fertilizer inputs. Simple calculation for estimating your wheat fertilizer needs based on fertilizer and wheat price, residual soil nutrients and yield goal can be found at UNL Extension website.
Wheat Streak Mosaic Virus (WSMV) disease is transmitted by the wheat curl mite (WCM) and “green bridge” provides host plants for both virus and mite to survive and cause problems next year. Mace is wheat variety tolerant to WSMV and you should consider it if you had a history of WSMV in your field.
Recommendation: Tank-mixtures of glyphosate with 2,4-D or dicamba, or gramoxsone are usually very effective in controlling “green bridge”. Two applications might be necessary in some cases, but avoid applying these chemicals 2 weeks prior to planting to avoid herbicide injury.
2. Consider buying certified, fungicide-treated seed to prevent yield losses from seed- and soil-borne pathogens and eliminate germination and survival problems that may be associated with planting bin-run seed.
Lover test weights were reported this year from a number of producers that did not sprayed for stripe rust. Wheat leaves that were severely infested with stripe rust fell off prematurely and imposed a stress on wheat crop during the grain filling period. K-state researchers found that planting seed with lower than 55 lbs per bushel may require special attention such as shallower seeding depth, higher seeding rate, adjusting seed blower to blow out “chaffy” seeds, and germination test. For more information click here.
Seed-borne diseases including Black Chaff, Fusarium head scab and ergot observed in this year’s wheat crop. Soil-borne diseases including root, crown and foot rots are common if soil conditions are wet during germination period and yield losses can occur due to poor establishment. Click here for more information.
Recommendation: Plant certified, fungicide treated seed. If using bin-run seed send seed to a lab for germination test or do the germination test yourself by wrapping seeds in wet paper towel for 5-7 days and estimating percent that survived. If germination rates are less than 80% fungicide treatments are highly advisable. For list of fungicide seed treatments click here.
3. Variety selection is critical part of every cropping systems. This doesn’t necessarily mean to select highest yielding variety from the book and expect highest wheat yield in the county. We need to become more familiar with other characteristics such as winter hardiness, disease tolerance, maturity, etc. For example, Byrd is one of the highest yielding varieties commonly planted in SW Nebraska, but it is very susceptible to stripe rust; therefore, you need to be tracking progression of stripe rust throughout the season and be ready to spray preventively. This year $20/ac investment on spraying stripe rust on Byrd made approximately 30 bu/ac yield difference. For Nebraska Extension Fall Seed Guide click here.
Reference evapotranspiration (ET) in the Upper Republican NRD ranged from 4.18 to 5.24 inches in this 17 days period (from 0.25 to 0.31 inches/day), with area to the south and with less rain having larger ET. Two storm came through SW Nebraska on August 5th and August 8th, each carrying from 0.5 to 3.0 inches. Rain really helped all dryland crops as it came at the right time and after good growing conditions we had in June and July. Hopefully the trend will continue to produce outstanding dryland yields for this area.
To more accurately estimate rain and crop water use on your farm, look at the map (attached) provided, obtain weekly reference ET value from location closest to you and multiply that value by crop coefficient provided in the table.
Reference evapotranspiration (ET) in the Upper Republican NRD ranged from 1.70 inches at north parts of Perkins County to 2.20 inches in south Dundy County; we received between 0 and 1.70 inches in rain. To more accurately estimate rain and crop water use on your farm, look at the map provided, obtain weekly reference ET value from location closest to you and multiply that value by crop coefficient provided in the table.
Weeds control in wheat stubble
Time to control weeds in the wheat stubble! New Cropping systems specialist from Panhandle Research and Extension center, Cody Creech, suggested 3 steps to control weeds in wheat stubble: (1) Carefully identify weeds that are present in your field, (2) spray weeds kochia, Palmer pigweed, pricly lettuce, Russian thistle and other tough to control summer annuals with tank-mix of glyphosate, dicamba and/or 2,4-D to prevent seed development (3) monitor for winter annual weeds like rye, marestail and cheetgrass and plan timely herbicide application in fall and early spring. For more information click here.
Corn is at reproductive growth stage. Adults of Western Bean Cutworm have been emerging in past week and spraying has been done in the area. UNL’s recommended threshold for insecticide application is 5-8% of corn plants have egg masses and/or small larvae.
Sunflowers are at V5 to butonization stage. Field peas harvest is done. Soybeans are at R2-R4 growth stage (setting pods). Milo is at booth stage. Potatoes in tuberization stage. Dry beans are at 80%-full cover. Sugarbeets are at full cover.