Issue 4 June 4th, 2015 Angie Johnson, Agriculture & Natural Resources Extension Agent Steele County County Highlights We just cannot seem to shake off this cool weather! On Friday, May 30th, the Finley NDAWN station reported a low temperature of 29 F at 4:50AM. However, the duration of time did not seem to be long enough to have detrimental frost damage. We were able to survive from Mother Nature s attack again! An unexpected rain shower occurred in Finley on June 2nd with the NDAWN station reporting 1.47 inches! Drown out areas are now expected in some low lying fields. I guess we no longer need to worry about the threat of a drought this spring! The extended forecast looks good, with temps in the 80 s to start bringing on some heat. Edible beans are beginning to emerge and winter wheat is not too far off from heading, as the flag leaf was visible in a field south of Aneta. Keep an eye out for pesky weeds now, as the best time for a post-herbicide application is when weeds are from 4-6 inches tall and during temperatures that are above 50 F at night. In regards to cattle producers, make sure your calves are vaccinated prior to pasture turnout. Diseases such as pinkeye and blackleg can be devastating in a herd, and so a vaccination protocol planned by you and your veterinarian can help prevent these diseases from occurring in your herd. A vaccination record at sale time can also increase your check, as feedlot buyers tend to pay a premium for calves that have had their vaccinations. Always remember to keep vaccinations cool, and read and follow label instructions. Local Rainfall & GDD Finley Mayville Pillsbury Cooperstown Corn GDD (Plant Date: 5/1/15) 269 289 268 276 Compared to 2014 NA 324 326 NA Compared to 5 year average NA 324 301 NA Wheat Accumulated GDD (Plant Date: 4/15/15) 963 965 958 943 Compared to 2014 NA 973 968 NA Compared to 5 year average NA 1013 982 NA Sunflower GDD (Plant Date: 5/11/15) 291 313 298 298 Compared to 2014 NA 400 405 NA Compared to 5 year average NA 377 360 NA Rain since May 28 1.70 0.36 0.41 0.39 Phone 701.524.2253 Cell 701.799.9951 angela.b.johnson@ndsu.edu
Counting Soybean Plants By: Hans Kandel, NDSU Extension Agronomist Broadleaf Counting soybean plants just after plants are up and in the cotyledon or unifoliate growth stage is a good method to evaluate the crop stand. Based on various hail loss studies and other research, the minimum stand for soybean in North Dakota is suggested to be around 75,000 plants per acre, which is approximately 50% of the recommended stand. If you use the hula hoop method to estimate the number of plants in solid seeded fields, you would need a minimum of 1.75 plants per square foot. The hula hoop method for solid seeded soybean stand counts depends on a circular hoop with a known diameter. The hoop should be tossed randomly at five different locations in the field and plants should be counted within the hoop. The area of a hoop can be calculated by the formula: Area = πr2, where r is the radius (or half the diameter of the hoop) and π (pi) is approximately 3.14. So with a hoop diameter of 24 inches the area is 3.14x122 = 452 square inch / 144 = 3.14 square feet. If the average number of plants in this hoop is 6, the population estimate can be calculated to be 6/3.14 (area of the hoop in square feet) x 43,560 (square feet per acre) = 83,236 plants per acre. When you use 30, 14, or 7 inch row spacing, you need at least on average 4.3, 2, and 1 plants per foot of row, respectively, to equal 75,000 plants per acre. It is important to count several feet per row at various locations per field and average the numbers to estimate the stand. When you have a 50% reduced stand, yield reduction will be somewhere between 10-20% of the potential yield of a timely planted soybean field with 150,000 established plants. Soybean stands usually are not uniform throughout the field and there will be areas with higher or lower plant counts. With uneven emergence and gaps between plants, yields may be lower compared with an evenly distributed low stand of 75,000 plants per acre. Plants may not establish in saturated parts of the field Soybeans have the ability to compensate for a low number of plants per acre by additional branching, more pod production per plant, more seeds per pod, and increased seed size. The plants in low population environments may have branches lower on the stem that break before or during harvest thus increasing the potential for greater harvest losses. Also some of the pods will develop lower on the plant. Evaluating Emergence Uniformity in Corn By: Joel Ransom, NDSU Ext. Agronomist Cereal Crops Corn is less flexible than wheat and soybeans in filling in gaps in the row after emergence and it also does not compete well with other nearby plants early in the season. Therefore, stand uniformity is a much more important goal with corn than with many other crops. The optimum scenario for corn is that every seed that is planted emerges on the same day with no skips or doubles. Achieving perfect uniformity of emergence is unlikely, even with the best of conditions and equipment. Nevertheless, better uniformity means higher yields so striving for improved uniformity will help improve productivity and profitability. Though there is no management practice that can ameliorate uneven stands at this point,
evaluating the uniformity of stands can be a useful learning exercise for future years. What are the yield loses associated with variable stands? For the past two years, with initial funding from the North Dakota Corn Growers and under the leadership of Lindsey Novak, a graduate student in Plant Sciences, a number of Area and County Extension Agents have assessed plant stand uniformity and measured its impact on yield. Averaged over all field locations, they found that within a planter width, the most variable row yielded 9 bu/a less than the least variable row (Table 1). The most common problem causing the variability was variability in emergence date and not skips and doubles. In fact, doubles were not a common problem in most fields, suggesting that most planters used in the fields sampled were very good at ensuring singulation. When measuring the yield loss on a plant basis, skips were the most impactful, followed by plants emerging 11-17 days after early emerging seedlings (Table 2). Plants next to a skip could add 10% greater yield when compared to normal spacing, but this was much less than the 50% needed to totally compensate for the lost plant. Plants next to a late emergers were able to add 5% greater yield, but again, they could not completely compensate for the loss of production by plants emerging later. There are a number of causes of poor emergence uniformity. Skips can be caused by non-viable seed and one should expect some skips as seed lots normally have germination percentages around 90 to 95. Doubles can be traced back to a planter problem. Though doubles generally do not result in a yield reduction (data not shown), they are not an efficient use of seed. Difference in the timing of emergence is caused by differences in access to soil moisture by the seeds, differences in soil temperature and/or seeding depth. Uniform moisture was a big issue for many fields earlier this spring. Determining the optimum seeding depth is not always easy and is a key decision impacting emergence in dry soils. Planting into moisture is recommended if no rain is forecast in the next 5 to 10 days. Planting too deep, prior to a heavy rain, on the other hand can slow emergence and in heavy soils that are prone to waterlogging, result in stand loss. The cool weather this spring accentuated emergence problems. Small differences in the temperature that the seed encounters can be caused by difference in depth of seeding and the amount of residue that is retained directly above the seed. Uniform seeding depth (planting speed impacts this) and uniform residue cover should be evaluated if you are disappointed in the uniformity of emergence timing this year.
Stripe Rust Detected in ND By: Andrew Friskop NDSU Extension Plant Pathology Cereal Crops On Monday June 1st, a wheat leaf sample collected by Dr. Janet Knodel was confirmed as stripe rust. On Tuesday, the IPM scouts in central and northeast North Dakota also documented the presence of stripe rust. This information combined with the early development of the disease in states to the south, we can expect that stripe rust is probably widespread on susceptible varieties on the eastern half of the state. I have not received any reports from western side of the state, but now is a good time to start scouting for the prevalence of this disease. How common is stripe rust? Stripe rust is often considered to be the least common wheat rust in ND. The last widespread stripe rust event in the state occurred in 2012 and several fields had high levels of stripe rust that required a fungicide application. What are the ideal conditions for disease development? The sporadic occurrence of stripe rust is largely explained by the environment. Stripe rust development is favored by cool nighttime (50-60 F) and daytime (below 80 F) temperatures with frequent moisture events such as heavy dews and rain; conditions that were readily observed during May. Where does stripe rust come from? Like all other wheat rusts, the stripe rust pathogen survives on living plants in the south and produces spores that are carried by winds north along the Puccinia Pathway. The route of spore travel is similar to the Central Flyway used by migrating waterfowl. This year Kansas and Nebraska reported several fields of high stripe rust incidence and severity producing an ample spore source for the neighbors to the North. This spore source combined with the cool wet weather experienced in May has contributed to the early documentation of stripe rust in ND. How do you differentiate between stripe rust, leaf rust and stem rust? Spring wheat leaf with stripe rust. Notice the orange -yellow color of the pustules. Both color and rust pustule shape can help differentiate between the wheat rusts. Mature stripe rust pustules are yellow to orange and appear in an elongated stripe on the leaf. In early stages of stripe rust development, the typical elongating stripe lesion is not common and color must be used to identify stripe rust (Figure 1). Leaf rust has oval shaped pustules that are reddish-brown on the leaf blade (Figure 2). Stem rust primarily occurs on the stems of susceptible plants, but can also be observed on the leaf blades as dark red-brown irregularly shaped pustules. Wheat leaf showing both leaf rust and stripe rust. Notice differences in the color and shape of the pustules.
Patience on Yellow Corn, but React to Yellow Wheat Now By: Dave Franzen, NDSU Extension Soil Specialist Most wheat fields are in the 3-5 leaf stage and have some yellow in them, especially in areas receiving near record May rains. Now is a good time to stream UAN and maybe a little ammonium thiosulfate or ammonium sulfate solution to avoid a large protein dockage and perhaps protect yield. Application of N/S would best be done sooner rather than later. Stream nozzles can also work, but greater wind speeds break up the stream pattern sooner with nozzles than stream bars. Adding ammonium thiosulfate to the mix increases the severity of any leaf splash under high wind conditions. Be sure the yellowing isn t due to disease or another condition. This is another case where a crop consultant can be a great benefit and help confirm the probable causes of a poor crop. Corn is yellow mostly because the soil is still cold (put your hand in the soil- it feels like an icebox), the wind is beating the young plants up, and the lingering effect of frost(s) still takes a toll. Growers should be patient with the corn until it approaches V-5, then assess whether N/S is a problem and take remedial action. Until then, patience should be the rule. In both conditions, it makes no difference to the plant what form of N is used as long as the plant can get to it. Avoid lowrate slow-release products on wheat, not because the products are not effective if used at similar N rates to UAN or urea, but because they are no more efficient in wheat uptake than UAN or urea and can be as much as 8 times higher in cost. The smart money is on more traditional products for yield and protein increases. Ash Anthracnose A Recurring Problem By: Joe Zeleznik, NDSU Extension Forester Cool and moist weather during the period of ash budbreak has again led to high levels of ash anthracnose, a leaf disease common to our region. Defoliation of ash trees is the most commonly observed symptom in spring, with green leaves littering the ground under infested trees. Additional symptoms of ash anthracnose leaf infections include brown-to-black blotches on leaf margins, causing leaf distortion, and small purple-to-brown spots in the middle of leaves (see photo). Several successive years of heavy defoliation may cause twig and branch dieback. Trees that lose leaves in spring will often grow new leaves. Re-foliated leaves are often smaller and the crowns of affected trees may appear thin. Treatment with fungicides is usually not warranted. Fungicides are effective only as a preventative treatment and should be applied as leaves begin expanding. Treating trees now can prevent mid-season infections, but infection is more common in a wet, cool spring, rather than during the drier, warm summer. For most large trees, fungicide applications aren t very practical. A light application of fertilizer (1-3 pounds of nitrogen per 1000 square feet of soil surface around the tree) may help reduce stress on highly susceptible ash trees. The fungus that causes ash anthracnose overwinters in the upper parts of trees in seed samaras, on twig cankers, and on any other infected plant part that remains attached to twigs, so raking and destroying fallen leaves and twigs will only help reduce inoculum rather than completely eliminate it. As a result, ash anthracnose is a recurring problem on ash as long as we have wet, cool weather during budbreak. Disease severity, and therefore the extent of spring defoliation, varies from one year to the next, and among individual trees. Note the dead leaf margins and distorted growth in the 1st photo. The 2nd photo shows a dead leaf margin plus small dots where the fungus has entered the leaves through natural openings/ wounds created by summer feeding by the ash plant bug.
NDSU Extension Service Steele County PO Box 316 Finley, ND 58230 Phone 701.524.2253 Fax 701.524.1715 June 4th Through June 10th Weather Forecast By: Daryl Ritchison Asst. State Climatologist/Meteorologist Some of the warmest air of the season is expected in the next 7 days, but that heat is going to hold off until early next week. In the short term, below average temperatures are projected through Saturday as the cooler air that moved into the region behind the thunderstorms from Monday Night into early Wednesday morning lingers through Friday. Additional moisture and the associated cloud cover will keep temperatures in check on Saturday. The rain on Saturday will be associated with an area of low pressure that will move out of the northern Rockies on Friday, impact western North Dakota late Friday into Friday Night and the rest of the state into western Minnesota on Saturday. This particular storm does not appear to be as strong as some of the previous systems. Although most places will record rain, amounts are expected stay around 0.50 inches or less with the localized higher totals in the heavier thunderstorms to be around one inch. Once that low pressure center passes through, Sunday through Wednesday look mostly dry and trending much warmer. The warm up will be associated with a ridge of high pressure aloft that will develop over the Rocky Mountains and move east in association in many ways to activity in the tropical western Pacific Ocean. The core of the warmth will occur on Monday and Tuesday with indications that on Tuesday perhaps a 90 high may be reached for only the second time this year in the state of North Dakota. Ninety degree heat will probably be the exception, but widespread 80s are anticipated. Warmer temperatures will also bring higher relative humidity values, with dew points climbing into the 60s. The Red River Valley will likely achieve the highest values, which is climatologically the most favored location for such values. EXTENDING KNOWLEDGE. CHANGING LIVES. County commissions, North Dakota State University and U.S. Department of Agriculture cooperating. North Dakota State University does not discriminate on the basis of age, color, disability, gender expression/identity, genetic information, marital status, national origin, public assistance status, race, religion, sex, sexual orientation, or status as a U.S. veteran. Direct inquiries to the Vice President for Equity, Diversity and Global Outreach, 205 Old Main, (701) 231-7708. This publication will be made available in alternative formats for people with disabilities upon request, (701) 231-7881.