An Agronomy Publication brought to you by Two Rivers Cooperative.

©2016 Two Rivers Cooperative

TRIBUTARY

TheSOIL REPORTThe

APRIL 2016

Consistency counts when it comes to corn yields. Uniform stands and emergence can either create the ideal situation for a positive yield outcome or leave your fields in a deficit from the get-go. Producers need to be vigilant from the very beginning, double-checking planting depth and placement to ensure optimum emergence and germination.

Even if best efforts are made by the producer, emergence and stand problems can still occur. Figure A explains issues commonly seen shortly after emergence and the factors that could lead up to such problems. Scouting fields should begin shortly after planting, and if you are seeing anything similar to these conditions, the decision should be made quickly

whether or not to replant. If you are at all questioning if you have reached your threshold to replant, I or any of the agronomy staff would be happy to check your fields with you. This is not the year to financially miss out on yield boosting opportunities.

DIAGNOSING POOR CORN STANDS & EMERGENCE PROBLEMS Brett Schippers - Agronomy Sales

Large Skips or Naked Ground 1. Planter Malfunction 2. Rodent or Bird Damage - Look for Signs of Digging

Poorly Developed Shoots & Root Growth

1. Disease Pressure - Inspect Seedlings for Disease Symptoms 2. Slow Seedling Vigor Due to Hybrid Selection or Cool Soils

Brown or Soft Seedling Dead or Dying Seedlings

Seedlings That Have Shoots or Roots with White or Pinkish Mold Fungal Attack

Dark Colored Roots & Crowns Pythium &/or Fusarium Fungal Diseases

Leafing Out Underground

1. Premature Exposure to Sunlight from Unfit Soil Conditions 2. Planting too Deep Causing Compaction or Soil Crusting

3. Extended Exposure to Acetanilide Herbicides such as Harness, Dual LL or Outlook

What You See What the Problem Could Be

Figure A (above) explains common issues seen in fields and what could cause those.

Corn with emergence issues.

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Over the last few years, our trade area has seen a growing number of corn rootworm injury issues. Rootworms cause damage by the larvae feeding on the corn roots, significantly impacting yields and your bottom line. Genetically modified corn with Bt rootworm traits should kill western and northern rootworm larvae. However, in recent years we have observed Bt rootworm hybrids in continuous corn and soybean to corn rotations showing western corn rootworm resistance. To date, there have been no known cases of northern corn rootworm resistance to Bt varieties, but I don’t think we should take it off the table completely when thinking ahead to future growing seasons. We need to learn how to deal with this pest in a way that doesn’t solely lean on specific hybrids for protection.

A diversified approach is the best method when dealing with corn rootworm. This pest isn’t leaving us anytime soon, so producers should be penciling out a long-term pest management program. There are a few key points to think about when planning for this coming growing season, as well as years ahead.

Crop rotations remain your best line of defense for the rootworm. Rotation-resistant northern corn rootworm is present in Iowa; however, rotation resistance by western corn rootworm

is extremely rare in our state. Rotating to a non-host crop will most likely break the life cycle of western corn rootworm and rotation-susceptible northern corn rootworm. At the very least, think about rotating out of corn once every five years.

Another mode of protection is looking at our hybrid structure when choosing your seed. By using a corn hybrid that contains Smart Stax or two below ground traits, you are ensuring a second rootworm Bt trait which could lessen your chances of your corn field being susceptible. It is also important to note that due to the Bt resistance issue with western corn rootworm, the utility of a pyramid is reduced.

Whichever road you choose, it is important to remember it needs to be a multi-layered, multi-year approach, and it may take some creativity by both you and your agronomist. However, I know we can work together to find a solution to combat this aggressive pest.

MANAGING CORN ROOTWORM Jay Van Woerkom - Agronomy Sales Manager

northern corn rootworm beetle western corn rootworm beetle

information provided by Iowa State University Extension and Outreach

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Although we cannot predict the weather that ultimately determines the extent of inhibiting diseases and pests, we can be prepared for them with three products in particular that I believe offer the best protection and bring added benefit to crops. These products focus directly on diseases and pests that we have experienced growing pressure from within our trade area over the last few years. Although producers may shy away from added inputs during these unsettling times in the market, they ultimately pay for themselves in the long run in terms of yield protection.

ILEVO® & SUDDEN DEATH SYNDROMESudden death syndrome (SDS) has become an increasingly

present disease in our trade area over the last two years. Scientifically shown, the weather we have seen in the past two years should have inhibited the spread of sudden death, however, that has not been the case. It is almost impossible to know if and when sudden death will onset but preparing for it before it comes is the only line of defense.

ILeVO® is the first and only seed treatment for sudden death and nematode activity. It also has added-value with seed-zone activity against soybean cyst nematode (SCN). Both SDS and SCN are two of the most yield-robbing pests in soybeans. With ILeVO, soybeans can reach their full yield potential because plants are healthier and perform better even in high-risk SDS areas, like the Two Rivers trade territory.

ILeVO was evaluated in more than 200 fields with visual symptoms of SDS during the 2011-2014 growing seasons. In those research trials, ILeVO yields were 2-10 bushels per acre higher than with other fungicide, insecticide treatments. That can make a significant difference in your bottom line during a time where every bushel count.

PRIAXOR® & NORTHERN LEAF BLIGHTPriaxor is a fungicide that works on a large variety of crops for

multiple types of fungi. It not only has the longest-lasting disease protection, but it also provides post-infection control and has added plant health benefits. We suggest Priaxor primarily to combat the northern leaf blight pressure we have seen since 2015. It seems to be the superior product in controlling the pest.

HEADLINE AMP® PAIRS WELL WITH PRIAXOR

Headline AMP allows you to maximize the potential in every

corn plant. By delivering more bushels of corn than any other fungicide, Headline AMP ensures maximum grain production, all while controlling the most troublesome diseases that attack corn.

One of the active ingredients in Headline Amp is F500, which allows the plants to grow more efficiently and focus their energy on producing higher potential yields. In fields that are especially disease-prone or managed on a corn-on-corn, no-till or minimum-till basis, have had improved results with a pre-tassel application of Priaxor followed by an application of Headline AMP between VT and R2 stages. This is also cost effective because you can tank-mix with your post-herbicide to make only one pass in the field.

By incorporating these beneficial products into your input lineup you are putting added bushels into the your bins. Although the thought of adding input dollars is slightly unnerving, you can rest assured that you have protected your investment to the best of your ability. If you have any questions about these products and how they will work with your seed selection, please contact myself or one of the other agronomy team members.

PRODUCTS THAT PACK A PUNCHBrent Van Kooten - Agronomy Sales and Precision Support

190 Sudden Death Syndrome Trials Across USAAverage = 5.4 Bu/Acre

Cover crop acres are on the rise in south central Iowa, and we are seeing an increased interest from producers wanting to gain information and statistics on the crops. We are doing the best we can to also educate ourselves, as agronomists, on this crop rotation so we can provide our producers with the necessary tools to warrant success. One aspect of the cover crop process that seems to still be looming in the gray area for producers is knowing how to effetively and safely terminate it. There are three modes of termination-herbicides, rolling or crimping, and tillage. The most common mode is herbicide, but there are some key factors to remember if this is the route you choose.

The effectiveness of a herbicide terminating a cover crop depends on the particular crop species and growth stage, the rate at which the herbicide is applied, and environmental factors. Cereal rye, the most common cover crop in our area, is easily controlled with a herbicide treatment.

Paraquat and Glufosinate are the two main contact herbicides available to control cover crops. They work by only affecting the parts of the plant they come into contact with. It is a great method for small, annual plants. This does not mean they can’t be used on overwintering cover crops that would be larger at the time of termination; it just means the spray volume may need to increase. A volume minimum of 20 GPA can help improve coverage when encountering dense canopies.

Translocated herbicides, such as glyphosate, move to the plant’s growing points so complete coverage is less of a concern than with contact herbicides. Due to the highly variable environmental conditions typically seen during the spring season, a one pound acid equivalent rate of glyphosate is recommended. Label instructions and recommendations can give you a better idea of formulations and guidelines.

Waiting to terminate your cover crop with a herbicide after your commodity crop is planted can be very risky. Your options are limited and the cover crop has the potential to turn into a uncontrollable weed. Iowa State University researchers generally recommend terminating the cover crop with herbicide 10-14 days prior to planting corn to protect yield. The timeframe for soybeans is less critical than it is for corn. Be sure to check with your crop insurance agent to know the termination requirements prior to planting corn or soybeans.

Rolling or roller-crimping is another method to terminating your cover crop. This alternative takes a bit more time and planning. For cereal rye, it is recommended to wait until the rye has shed pollen to get a consistent kill. Roller-crimping termination success is harder to achieve in a cover crop mix because the plants will be at different growth stages at the same time.

Tillage is the last viable option for termination but may fit better into some operations than others. For tillage to be an effective mode of termination, multiple passes across the field may be necessary. For most, this takes away from the point of using cover crops and the benefits such as soil health and erosion.

Whichever mode of termination you decide to use just be sure to check your fields after for skips or regrowth. For most, the uncharted territory of cover crops seems extensive. However, I encourage producers to at least try this approach on a few acres to start and see if it is viable for your operation. Two Rivers has a drill to plant the crop with and is here to answer any questions you may have along the way.

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ACTION PLAN FOR COVER CROP TERMINATIONAaron Steenhoek- Seed Sales Specialist/Agronomist

information provided by Iowa State University Extension and Outreach

Farmers are masters of the “To Do” list, and their thoughts are always moving to what is next in the process of producing a high-yielding crop while also maintaining financial strength. Although most of you are just beginning to get your crop in the ground, I am almost certain the idea of weed control is already on your mind because naturally it is the next step in the process to think about.

When looking at soybeans, studies have shown that early weed control is your most effective way to maximize yield potential so therefore it pays to plan ahead! Nick Harre, a Ph.D. student at Purdue, has made it his career to study weeds and in particular, herbicide-resistant weeds. He evaluated both crop and nutrient loss from living weeds and nutrient release from controlled weeds on soybeans. Competition from weeds up to four inches only minimally affected nutrient acquisition by soybeans, while competition from weeds eight inches or taller negatively affected acquisition. Soybean yields and grain oil content were also reduced.

The same can be said for corn. Applying a herbicide when weeds were four inches tall resulted in a 3% yield loss, and each delay approximately doubled the yield loss. Further more, a single-pass application usually doesn’t cut it in corn. Not only is a post emergence application needed, but a second pass should occur during the early growing season to kill off any weeds that came up after the first application. Chart 1 shows the projected yield loss in corn in correlation to weed size. Some growers may be fearful of the “added costs” that come with a two-pass protection plan. After referring to Chart 2 you see that in reality, it pays for itself!

Just as important as early weed control, is the challenge of working with herbicide-resistant weeds such as waterhemp. Also in Nick Harre’s study, results showed that a single application of a PPO-inhibitor such as Valor SX only provided sufficient control for a short period of time. Products such as Warrant or Dual II

Magnum are only regularly effective on small-seeded broadleaves. However, when both types of weed control were tank mixed together, results showed the most consistent and prolonged control of waterhemp. The best way to kill round-up resistant weeds is to keep them under the dirt. If growers can do that, then over time they will be reducing their field’s weed bank.

As we stress the idea of early-season control and multi-level herbicide protection, some growers may be concerned with the yield impact of early-season herbicide injury. In this same Harre study that lasted over the course of three recent years in weather conditions identical to our own, no soil residual herbicide combination reduced yield when applied according to labeled rates.

The idea of managing resistant, heartier, early-developing weeds is very real now. The weed control plan you have been using for the last 20 years may no longer cut it. Consult with your agronomist to put a plan together for optimal weed control on each of your fields. Weeds have always been our enemy, and it looks as though they are only becoming more of a problem.

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WEEDS ARE THE ENEMY

2” 0%

4” 3%

6” 6%

9” 14%

12” 22%

Application Timing (Weed Size)

Corn Yield Loss (Early-Season Competition Only)

Cost of 2-Pass Herbicide for Weed Control $6.00 - $10.00 more per acre

4” Weeds lead to a 3% Yield Loss 3% x 180 bu x $3.50 = $19 ROI per acre

6” Weeds lead to a 6% Yield Loss 6% x 180 bu x $3.50 = $40 ROI per acre

CHART 1

CHART 2

information provided by Iowa State University Extension and Outreach

information provided by Iowa State University Extension and Outreach and the Corn+Soybean Digest

Aaron Steenhoek- Seed Sales Specialist/Agronomist

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ALWAYS LEARNINGAnyone who says you stop learning after a certain age has never

met Bert Bandstra. Even after 55 years of farming near Oskaloosa, Bert soaks up each opportunity to learn about new farming practices and better his operation.

You could say it’s in Bert’s nature to stay busy making things better. With his wife, Elaine, always nearby ready to assist, he is either farming or using his mechanic and carpentry skills. In fact, after buying the farm he and Elaine still reside on, Bert built their home in 1977 where they raised four children and welcome nine grandchildren.

The 550 acres of row crops that Bert currently farms receives a special kind of attention. While the goal is still to maximize yield, Bert also believes in achieving that while trying and testing nutrient and conservation practices that protect those precious acres and the investments placed in each.

After deciding to exit out of cattle and swine production in 2011, Bert needed to find a replacement for his manure applications. He had seen how the added benefits of the manure had helped his row crops and the negative effects of not using it. This led Bert to explore the incorporation of cover crops.

In 2013, to take the first step in testing cover crops, Bert drilled in 15 acres of rye himself. His initial thoughts were that if they didn’t do much to aid in the growth of the row crops, they would at least be helpful in holding the soil in place. The rolling land Bert farms was always requiring special attention, such as terraces, to keep land in place. Bert came to find that the cover crops did offer a helpful hand in holding the soil. Not only did they lessen soil erosion, it reduced the nutrient runoff, therefore helping better utilize the nutrients in the soil as well.

Bert wanted to test a different route for cover crop placement the second year to see if he could increase the efficiency of planting. He had his cover crops dispursed in the field with a dry fertilizer spreader but came to find that the stands were not near as good as they should have been. He was back to drilling in his cover crops the third year but instead utilized the services of Two Rivers Cooperative. Today, Bert has 200 acres of rye drilled in his field by the Cooperative.

With a few years of learning how best to plant cover crops in his no-till acres, Bert has also discovered other secondary benefits of the added crop. Less weed pressure, better sudden death syndrome control, and reduced soil compaction have all been noted by the Oskaloosa farmer on his cover crop acres.

The testing, researching and learning is far from over for Bert Bandstra. Although he currently plants only rye, he is looking into the benefits oats may bring. Building up the organic matter in the soil is also a focus of Bert’s, and he plans to use his grid soil sampling to direct him to try new farming practices that give his soil the most value and longevity. If you don’t see Bert at any of the various field days around the state, you can bet he is busy taking

advantage of his own in-field testing, because as Bert Bandstra knows, we can always learn something

new in farming.

Oskaloosa farmer, Bert Bandstra continues to learn new farming

practices even after 55 years.

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The El Nino weather pattern may be lessening in intensity, but its impacts are still being felt in the agriculture industry. With the above average temperatures we saw going into winter, the question now should be, “What happened to our fall-applied nitrogen?”

The majority of nitrogen (N) loss occurs in two forms, leaching of nitrate-N (NO3- -N) and denitrification. Denitrification is the lesser issue of the two due to soil temps being colder and temperatures in the upper 30’s when we received significant rains in December. Leaching has more than likely occurred because, although the soils were cold when those late season rains fell, they weren’t frozen yet. To add to that, the rainfall was significant enough that we can assume surface runoff occurred and water ponded into depression areas. The issue is, this perfect storm created N loss that won’t be uniform across the field. With those depression areas, N moved with the water through tile drops and not through the soil. When this happens we also loose residual soil profile nitrate-N after both corn and soybean crops, not just from

fall N applications.The most common form of N applied in the fall is anhydrous

ammonia. When anhydrous ammonia is injected into the soil and forms ammonia, the positively charged substance attaches to the negatively charged soil, ensuring it will not leach out of the soil. Ammonium is converted biologically to nitrate by the process called nitrification, and the rate of nitrification depends heavily upon soil temperatures. As I mentioned earlier, we saw temperatures above the freezing point much later in the year than we usually do, thus affecting the nitrification rate. Time is also a factor, because the longer ammonium is in the soil, conversion will take place if the soil temperature remains warm, like they did in late 2015. Nitrification in inevitable, but with fall soil temperatures below 50oF and falling, the biological activity slows considerably. Our concern is with the warmer than normal temperatures later in the fall, the nitrification process may have continued longer than we would usually see.

No one can say for sure what we lost last fall or this spring, we can only have educated scenarios. For those producers who coupled their application with N-Serve, we believe they will see less of a loss. However, tissue tests and visual field observations will be our best tools to evaluate our nitrogen needs.

Two Rivers Cooperative would like to announce the addition of a John Deere R4030 to our equipment fleet. This row unit will allow us to make in-season applications, utilizing imagery for variable rate urea applications. We are able to apply nitrogen only where needed, positively affecting your bottom line and crop coming out of the field.

Matt Van Weelden- Agronomy Operations Manager

DID FALL APPLIED NITROGEN STICK AROUND?

JUST IN TIME FOR SPRING FIELD WORK

TAKE NOTE:

NITRIFICATION - the conversion of ammonia first into nitrites then into nitrates by nitrifying bacteria.

DENITRIFICATION - the conversion of nitrites and nitrates into free nitrogen.

109 South StreetPella, IA 50219800-223-5512

www.tworivers.coop

Locations in Pella - 641-628-4167Otley - 641-627-5311Monroe - 641-259-2232Tracy - 641-949-6411

A CornerPost Marketing Communications Publication

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Brent Parker, a Central College student, will be interning within the agronomy department at Two Rivers this summer. He is eager to learn the ins and outs of the cooperative system. A Bussey native and the son of a cooperative member, Brent is familiar with the trade territory and the duties he will be given this summer. A few of his responsibilities will include field scouting, sales shadowing and caring for the Answer Plot. We are looking forward to having Brent join us for the summer. If you see him out working this summer, please be sure to introduce yourself!

BUSSEY NATIVE IS OUR 2016 SUMMER INTERN