Conditions have been wet and cool across many midwest states this planting season. What does this mean for your planted soybean fields?
Soybean stand loss early in the season is often due to “damping off” which is a broad term which refers to seed and seedling diseases. The four big ones are pythium, phytophthora, fusarium and rhizoctonia. Pythophthora and pythium are often the two most common and troubling for us in our market area. These two pathogens are sometimes also referred to in slang as “water molds” as they thrive in saturated soils with free water. They have spores that can survive in soil and crop residue for long periods of time and when soils become saturated with free water spores can detect plant root exudates. They then literally swim to the root and infect. Quite simply, without wet soils they are not able to readily infect, so in drier years they are typically not an issue.
Stand loss early in the season with early-to-normal planting dates is more typically associated with pythium because it thrives in cold wet soils; while phytophthora infects more readily in somewhat warmer wet soils. With the recent cooler weather, pythium may be the leading candidate as the pathogen causing any stand loss/damping off within fields but an actual lab diagnosis can often be the only way to 100% confirm the pathogen in question as all four of the major soybean damping off diseases can be hard to distinguish from one another with the naked eye and their infection environments can overlap each other.
Many soybean varieties offer native genetic resistance to specific races of phytophthora which is very valuable. However, there are many different races of phytophthora present even within the same field, so one specific phytophthora gene may not always be effective. Partial resistance or “field tolerance” is also a rating which you will see in most product guides which is just as important. The fungicidal components of virtually all complete soybean seed treatment packages also offers a level of protection against the damping off pathogens. However, that protection can simply be overwhelmed under high pressure saturated soil conditions and begins to slowly fade following the first few weeks after planting.
Use of Pre-Emerge Herbicides
Soybean seedlings may also be further stressed when PPO soybean pre-emerge herbicides containing flumioxazin, sulfentrazone, or saflufenacil have been used in conjunction with cool and wet soil conditions. Soybean pre-emerge herbicides containing these actives are quite common in the industry and used on lots of soybean acres as they are generally good at controlling problematic small seeded broadleaves such as marestail and waterhemp. These herbicides can cause some stunting of seedlings most often due to some minor to moderate burning of the cotyledons and hypocotyl as the seedling emerges through the soil/herbicide layer. Cool wet conditions make it harder for the young seedling to metabolize the chemical.
It is quite possible that any fields currently showing damping off symptoms may have more than one thing going on. Variety, pathogen and herbicide may all play a part.
Contact your local Hoegemeyer DSM or Agronomist for more information.
A great harvest starts in the SPRING when planting the right seed on your unique acres. Growers often reference corn suitability ratings to provide valuable insight to a hybrid’s strengths and weaknesses, and how that translates into productivity and profitability for their acres.
Know your soil profile
When it comes down to seed selection, growers should take into account the soil profile in each field. High soil pH is a common challenge in the Western Corn Belt. Decreasing soil pH through management practices is very difficult and typically not economical, so what should a producer do? “Plant a hybrid with good tolerance to high soil pH, a suitability score of 5 or higher,” states Craig Langemeier, Hoegemeyer sales agronomist.
The effects of high pH soils
Hoegemeyer is committed to providing growers products that can tolerate these stressful pH conditions. High pH soils cause a symptom known as Iron Deficiency Chlorosis (IDC). Several nutrients become harder for the plant to extract from the soil at a pH above 7.5 including phosphorus, zinc, iron and manganese. This may cause stunting, yellowing, interveinal chlorosis and even plant death in some hybrids.
Commitment to research
Hoegemeyer conducts extensive research on all products before they are brought to market. Research efforts have recently ramped up to provide high-performing pH tolerant products growers demand. During the 2016 growing season, replicated trials were conducted with over 70 entries at two high pH environment locations. This research aids in providing the right seed to perform in your soil type.
Selecting the right seed
Do you have high soil pH? Do you have the right seed to perform these acres? Different genetics are going to perform differently on each soil type, be confident you’re selecting the right seed for your farms – talk to your local Hoegemeyer dealer for placement recommendations. Check out the Hoegemeyer brand hybrids that are recommended for high soil pH here.
It is always a great feeling when you’re done planting and are ready to clean up and put the planter away. However, as the plants start to emerge, take some time and check out your fields. It may pay you a big bonus! As you go out to your field(s) take along a trowel and knife plus be prepared to take some notes as you inspect those newly planted fields.
Uneven Emergence and Stands - dig with your trowel and assess things.
• Was the seed placed in both wet and dry soil and did poor seed to soil contact occur in some areas?
• Are you seeing areas with poor seed furrow closure?
• Are the slower emerging seedlings planted in heavy trash areas that stimulated cooler soil or maybe caused the planting units to be lifted up more; or on the extreme, did the trash cause hair pinning?
• Does the depth of the seed vary because of clods or root clumps related to planter speed?
• Was the seed planted in wet conditions where mud accumulated on the depth gauge wheels?
• Are you seeing any insect pressure (wireworm is an example)?
• Don’t forget about gophers and turkeys digging up seed.
• Does the field have dramatic soil type changes or other problems to note?
• Are there areas where the soil was compacted by equipment or livestock tracks and/or truck load out areas?
• Are you seeing any chemical or fertilizer problems?
Planting in Cool or Wet Soil - can cause a lot of emergence problems.
• If soils were wetter when the field was planted, check for sidewall compaction.
• If soils were cold and overly wet, check for seed imbibition or see if germinating seedlings are “corkscrewing”.
• Are the slower/delayed seedlings in areas where the soil crusted?
• Check for cutworm, white grub or other insect problems.
• Are seedlings damping off in areas due to some soil borne pathogen. (Might see more in trashy areas.)
• If you use seed rebounders, did they drag any seed?
• Note if there were wet areas and where they were in the field around the time it was planted.
Planting in Cool or Dry Soil - can cause emergence problems too.
• If you are putting higher rates of fertilizer in furrow, check for fertilizer burn to the seedlings.
• If you are you seeing seeds that germinated and started to root and then died, they may have run out of moisture.
• Check for poor seed to soil contact, were there any clods?
Are You Seeing Doubles / Triples or Skips?
• Make sure you note this so that the planter problem is remedied before it is put in the ground again.
• Be sure to note any areas that indicate potential for weed problems and escapes.
• For future reference note any problem insect areas too.
These are some things to consider but be sure to check those fields; it may prevent a few headaches and pay you big dividends too!
, Don "Moe" Moeller
Corn, Don "Moe" Moeller, Emergence, Management, Planting, Soils, Uneven Emergence
It is already mid April and you’re ready to plant corn! Why is soil temperature so important? We all know that soil temperature should be hovering in the 50 degree area for corn to germinate but what many do not know is that it takes two things in the right amounts to properly start the corn seed germination process. One is the right temperature and secondly, the seed needs to absorb around 30% of the seeds weight in water to begin the process in cooperation with soil temperature. (Note: soybeans need to absorb about 50% of the seed weight.)
Please consider this! Many of the near term weather forecasts I have heard are saying cooler temperatures and some form of moisture which potentially may not allow near term soil temperatures to rise or stay like we hope it should. We have all heard of seed lying in the ground for up to three weeks before it emerges hence we may reason that with the help of today’s seed treatments the seed still germinates and produces corn … so what can happen?
Keeping in mind it takes the right (1) temperature and (2) amount of water to start germination, problems can arise in cool soil conditions! Even though the temperature is not adequate to start germination the seed still continues to absorb water through the germ area of the seed. The amount of water absorbed will go above and beyond 30% of the seeds weight to the point where the seed expands so much that it breaks the clear pericarp layer surrounding the seed. The longer seed lays in cool ground with its pericarp broken is like opening the barn doors wider to allow soil / disease pathogens unlimited opportunity to enter the seed. These pathogens may increase the possibility of seedling damping off and or surviving plants will be at a greater risk of disease infection that may show up later in the year in the form of fungal diseases like stalk rot or bacterial problems or weaker, susceptible yield robbed plants.
Consider that we still have a lot of time to plant for the best yield potential.
, Don "Moe" Moeller
Corn, Don "Moe" Moeller, Management, Planting, Soil Temperature, Soils
Much of the region has been blessed recently with moisture in some form – snow, sleet, hail, ice, and even rain. For most of us, the drought isn’t over yet, but this last weather system has helped relieve some of the deficit. Prior to the recent rains, I did some soil probing in a field near Columbus, NE. Throughout the field there was adequate moisture in the top 12-15 inches of the profile. The soil below this layer was quite dry. This same field has received over 2 inches of rain since then, and I’d expect that the moisture has made it deeper into the profile now. Rain events that yield 1, 2, or 3 inches at a time will be important for recharging the full soil profile. Why? Look no closer than your coffee cup. You’ll notice that water climbs ever so slightly up the side of your cup. This is called adhesion. The water is actually binding (loosely) to the cup. Water also likes to adhere to soil particles. When the top layers of soil are dry, new rainfall will first bind to the soil near the surface because adhesion is stronger than gravity. Only after the top layer of soil reaches field capacity will water begin to percolate down through the profile.
Your soil profile not only needs moisture from above, it also needs help in terms of management. I’ve noticed how nearby fields have absorbed the recent rains with different levels of success. Some fields showed signs of ponding and runoff. Other fields soaked up every drop. It’s not that the fields with no runoff were dryer (all of our fields needed rain). The difference is that some fields were able to absorb the rain at higher rates than others. Decisions on tillage, how much residue to leave, and compaction are making an impact on the amount of moisture that will available to the 2013 crop.
One comment on soil temperature…
Keith Glewen, UNL extension agronomist, forwarded some recent soil temperature data from the Mead, Nebraska area. Temperatures at the 4” depth had been on a slow climb up to the 50 degree mark in early April, followed by 4 straight days in the low 50’s starting on April 6 and ending on April 9. The soil temperature for April 10? 41.5 degrees. As you make early-season planting decisions, always remember that soil temperatures closely follow air temperatures.
, Ryan Siefken
Management, Moisture, Planting, Ryan Siefken, Soil Profile, Soil Temperature, Soils