Mississippi County
 |
 |
9/21/2007
Allen Wrather, MU Delta Center:
Soybean:
The current Asian Soybean Rust alert status for SEMO is at Warning as it was last week because it was found from 9/8 to 9/19 on soybean in several northeast Arkansas counties: Clay, Mississippi, Randolph, and Lawrence. We are actively scouting for rust in Missouri but have not yet found it. The weather has not been good for rust development the last 7 days, but it may still develop. I believe that southeast Missouri farmers should examine each of their soybean fields and determine growth stage and yield potential. If the beans in pods near the top of the plants are full sized or touching, then no action is needed because those plants are beyond the rust sensitive stage. If the beans in the pods near the top of the plant are still developing and the yield potential is 40 bu/a or greater, I suggest the field be sprayed with a fungicide like Quadris or Headline for general disease control, and test results from Georgia show that these products will provide some protection against soybean rust if applied 7 days before rust arrives. Most soybean planted in SEMO are beyond the sensitive stage except some of the mid-June planted irrigated soybean. A list of labeled fungicides for soybean foliage disease control is available at http://aes.missouri.edu/delta/muguide/foliarfungicides.stm.
Wheat:
Wheat seed intended for planting this fall can be protected from some diseases with a fungicide seed treatment. Fungicides can be applied to seed in the hopper box or by a commercial seed treater. However, commercially treated seeds have a more uniform coating of fungicide than hopper-box treated seeds, and, as a result, the seeds and resulting seedlings are better protected from diseases. A list of seed treatment fungicides for wheat is posted on the following University of Missouri web site: http://ipm.missouri.edu/ipcm/archives/v16n16/ipmltr4.htm
Anthony Ohmes, Mississippi County
Soybean:
Leaf samples sent in from two locations in southern Mississippi County this week had no soybean rust. Samples have been sent in weekly and will continue to be sent in until the end of the season. Early and most double crop soybeans are at late R5 to R6 as of this week. R6 is the stage when beans are touching in the pod at the 4th node from the top. This is the cut off stage for both irrigation and concerns for rust. The continued lack of rainfall and rapid accumulation of growing degree days has progressed harvest for all of the row crops grown in SEMO. Harvest has begun for dry land soybeans and yields have been extremely variable. Many expected soybean yields to be lower this season and so far this is holding true.
Wheat:
Wheat planting will begin soon. Keep in mind if you are the first to plant and have enough moisture for emergence, the first green fields will likely attract insects such as aphids. Be sure to monitor for aphids, especially during the first 60 days after emergence. First 60 day threshold is 3 to 5 aphids per foot of row.
9/11/2007
Dr. Allen Wrather, MU Delta Center:
The current Asian Soybean Rust alert status for SEMO has been raised to Warning because it was found on 9/8 on soybean in a field a few miles west of Jonesboro, AR. We are actively scouting for rust in Missouri but have not yet found any. The weather during the last 5 days has been good for rust to develop in SEMO. We believe that southeast Missouri farmers should examine each of their soybean fields and determine growth stage and yield potential. If the beans in pods near the top of the plants are full sized or touching, then no action is needed. Those plants are beyond the rust sensitive stage. If the beans in the pods near the top of the plant are still developing and the yield potential is 40 bu/a or greater, I suggest the field be sprayed with a fungicide like Headline or Quadris for general disease control or a product like Headline SBR, Quilt, or Stratego because these provide general disease control and rust control. Most soybean planted in SEMO are beyond the sensitive stage except some of the mid-June planted irrigated soybean. A list of labeled fungicides for soybean foliage disease control is available at http://aes.missouri.edu/delta/muguide/foliarfungicides.stm.
Anthony Ohmes, MU Extension
Soybeans:
Early planted Group IV soybeans have progressed to R6 or later stages of development. Group V and double crop beans are in a slightly wider range of development in our area. In these fields efforts to evaluate growth stage and yield potential should be concentrated. Fortunately, the Group V and double crop soybeans I have seen are at R5 or later growth stages. Continue to monitor for stink bugs on late maturing soybeans.
Wheat:
Some reminders as we move closer to wheat planting. Select well drained fields and improve drainage in wet spots. Applying 15-25 lbs of nitrogen along with P and K following corn, grain sorghum or rice can improve crop health and root system. If unsure of your soil nutrient levels have your soil tested.
Wheat planted prior to October is at increased risk of yield loss associated with aphid feeding, barley yellow dwarf virus and spring freeze injury. Other dates to consider are the average first frost and Hessian fly free date. Although wheat will germinate in soil temperatures as low as 40 degrees, late planting increases the risk of poor fall tiller development, winter injury, and heaving.
8/27/2007
Soybean
As of the end of last week, still picking up green clover worms and soybean podworms (corn earworm) in double crop soybeans. The location of podworm attack has been sporadic. I have primarily found the podworms and pod damage where beans have not lapped the middles due to stress and/or late planting. Continue to monitor insect pressure.
Wheat
As corn harvest gets underway, wheat planting will soon follow. Wheat yield trial information is available on line at: http://extension.missouri.edu/mississippi/varietytrials.shtml. The University of Missouri wheat performance books are available in extension offices.
Other information on wheat production, including seed treatments are available on the 'Wheat Links' page at: http://extension.missouri.edu/mississippi/ag.shtml.
Allen Wrather, MU Delta Center
Soybean
The current alert status for Asian Soybean Rust (ASR) is Caution, but we may elevate that during the next 10 days due to rust being present near southwest Missouri. As of August 23, rust was in a Oklahoma county very near to Neosho, Missouri. The weather during the next 10-14 days will determine if rust develops there and in our area. Farmers in our area, southeast Missouri, should not spray soybean with fungicides for ASR now or during the next 7 days. Relax, we are vigorously scouting local soybean fields for rust and will alert you if soybean need to be sprayed with fungicides for ASR. Even if ASR develops, many varieties will not need to be sprayed with a fungicide because they have passed the sensitive stage of growth, R6 growth stage (full sized beans) or beyond. Soybean planted in April and maturity group 4 varieties planted in May are beyond the sensitive stage. Maturity group 5 varieties planted in mid- to late-May and all varieties planted in June are still at a sensitive stage. Here is the current situation. As of August 23, ASR was spreading in south central Louisiana, east Texas, and east Oklahoma. ASR needs frequent rain and cloudy days to spread, and these areas have been getting rain lately. ASR is present in southwest Arkansas, but it is not spreading there. On August 12, ASR was found in a sentinel plot and in an experiment plot near Greenville, Mississippi. These plots were destroyed. Scouts have been thoroughly examining soybean for rust in that area and the rest of the delta of Mississippi, and so far no other infected plants have been observed. I don't expect ASR to spread and develop in our area until this hot, dry weather is over. We will keep you informed about the spread of this disease in other states.
8/14/07
Soybeans:
Dry weather is the primary concern. Soybeans use approximately 0.25 inches of water per day during pod development. If under irrigation, continue to stay on schedule. Disease pressure is currently absent in soybean fields. Soybean rust continues to spread in the south. The most recent find was in Washington County, Mississippi. One can continue to monitor rust progression on the web at: http://www.sbrusa.net/
Podworms are showing up in select double crop soybean fields. Group 4 early beans are R5 or later in development. However, in either case, you will want to monitor and prevent excessive pod feeding from these insects. Threshold is 1 worm per foot of row and when pod feeding exceeds 5%. There also some yellow striped armyworm in these fields. Yellow striped armyworms are leaf feeders and should be included in the leaf feeding complex of insects. Yellow striped armyworm can be identified by the black spot on both sides and the inverted Y on the head. Continue to monitor leaf feeding insects, which also includes bean leaf beetles and green cloverworms. Threshold for leaf feeding is 25% leaf defoliation during pod development.
Dr. Allen Wrather, MU Delta Center:
Soybean
On August 8-9, Asian soybean rust was reported to be spreading in south central Louisiana, Texas, and Oklahoma. Currently, ASR has been reported on soybean in 22 east Texas counties, two in southeast Arkansas, eleven in central Louisiana, one in Alabama, one in Florida, and three in Oklahoma. ASR has been spreading in the areas of TX, OK, AR, and LA that have been getting frequent rain. ASR does not develop well or at all when the weather is hot and dry, and it has not yet developed in the hot, dry areas of Mississippi and the delta areas of Arkansas and Tennessee. I don't expect ASR to spread into these areas or ours until the hot, dry weather is over.
Corn
On August 10, no loads of corn delivered to Bunge at Vicksburg, Mississippi has been rejected because of aflatoxin contamination; some loads of corn had this toxin but not enough to cause the terminal to reject it. Some corn delivered to terminals in Louisiana have also been contaminated with this toxin, but contamination levels were low. Aflatoxin is a serious problem, and corn farmers in southeast Missouri should take precautions to avoid this problem. Corn farmers that irrigated their corn this year and planted Bt varieties will experience fewer problems with aflatoxin than others. I suggest that farmers first harvest some corn in the corners of center pivot irrigated fields or dryland corn and have it tested for aflatoxin. If it has no aflatoxin then the rest of the irrigated corn will probably not be contaminated. But southeast Missouri corn farmers should never store wet corn for more than 24 hours on a truck or in a grain tank. For more information about this, read the news release in the current issue of MidAmerica Farmer Grower by Dr. Anthony Ohmes or visit http://aes.missouri.edu/delta/croppest/aflacorn.stm.
8/7/2007
Corn:
As of the end of last week, corn in the area ranged from 1/2 milk line to black layer (physiological maturity). Corn at 1/2 milk line to 3/4 milk line along with good soil moisture are also deciding factors in terminating irrigation. As you begin to harvest, monitor harvest losses under the header as well as behind the combine and make adjustments when necessary.
Soybean:
Pod feeding (stink bug and corn earworm) insect pressure is non-existent to low in the area. Bean leaf beetle numbers are slowly on the rise. Hot and dry conditions have kept disease pressure low, as well. Signs of Dectes stem borer are appearing in soybeans in the lower part of the county. Stem borers enter through a petiole and make there way to the stem. The first noticeable symptom of potential stem borer is one dead petiole on a normal looking soybean plant. Splitting the petiole and stem will reveal a very small borer.
Soybeans during reproductive phases are consuming 0.25 inches of water per day. Rain is needed to reduce the risk of pod loss and preserve bean quality. If one can irrigate, continue and do not fall behind.
Wheat:
Variety trial information is available from most university trials. The web link for variety testing: http://extension.missouri.edu/mississippi/varietytrials.shtml. Keep in mind the freeze was a major factor on yields this season. Planting date played a big role in our region on how well a particular field yielded. A freeze of that magnitude has not happened in over 100 years and hopefully will not occur for at least another 100 years. Do to the freeze and other variables, kept seed must be cleaned and a germination test should be conducted.
Jeff House, MU Extension, New Madrid County:
Soybean:
Bean leaf beetle numbers have risen slightly in New Madrid County, with exceptional hot spots that need treatment. Stink bug and podworm (corn earworm) pressure is low to non-existent in most areas. Hot, dry weather is keeping disease incidence low. There are areas of non-irrigated soybeans that have been without water too long to expect recovery of full yield potential, with some fields experiencing more than 50% loss.
Allen Wrather, MU Delta Center:
Soybean
Asian soybean rust is currently on soybean in 22 east Texas counties, two in southeast Arkansas, five in central Louisiana, one in Alabama, one in Florida, and two in Oklahoma. It has not yet developed in Mississippi or the delta area of Arkansas. Rust is on soybean in the areas of Texas and Arkansas that have been getting frequent rain the last few weeks. The weather in the rest of Arkansas, Mississippi, Louisiana, and our area is hot, and dry, and these conditions are not good for rust. According to my friends in Louisiana, soybean rust is not spreading there due to the hot, dry weather. I don't expect rust to spread in Louisiana, into the delta areas of Arkansas and Mississippi until the hot, dry weather is over.
Corn
On August 3, aflatoxin contamination was not a problem on corn harvested and delivered to river terminals around the Vicksburg, Mississippi area, and this is good. Generally, if aflatoxin is not a problem there then it will probably not be a problem here. This is because weather greatly affects development of aflatoxin in corn, and the weather is usually the same for the delta areas of Mississippi, Arkansas, and Missouri. Aflatoxin is a serious problem, and corn farmers in southeast Missouri should still be concerned. Corn farmers that irrigated their corn this year and planted Bt varieties will experience fewer problems with aflatoxin than others. I suggest that farmers first harvest some corn in the corners of center pivot irrigated fields or dryland corn and have it tested for aflatoxin. If it has no aflatoxin then the rest of the irrigated corn will probably not be contaminated.
7/25/2007
Corn:
Most corn in the area is denting and the separating line of starch and milk is 1/4 to ½ way down the kernel. At this stage of development corn is approximately 14 to 10 days away from physiological maturity or black layer, respectively. Identifying the line between starch accumulation and milk, referred to as the milk line, will help determine how much more water is necessary. Corn at 1/4 milk line will use approximately 3 inches of water to reach black layer and corn at 3/4 milk line will use approximately 1 inch of water to reach black layer. Water holding capacity of your soil will play a role in this decision, as well. Water holding capacity is influenced by soil texture (sand, silt, clay) and organic matter. Sand has the lowest capacity at 0.75 to 1.25 inches/foot and silt loam has the highest capacity at 2 to 2.5 inches/foot. A detailed chart for various soil textural classes is available on the web: http://www.noble.org/ag/Soils/SoilWaterRelationships/Index.htm
Soybean:
Our early soybeans are in various reproductive stages. Most of the soybeans I have looked at are between R3 and R4. Growth stages in soybeans is determined by identifying the main branch. On the main branch locate the top node of the newest unfolded trifoliate leaf and count down the branch four nodes. At the fourth node from the top inspect the cluster of flowers and or pods. At the R3 stage of development the flowers will be dried and 3/16 of an inch pods will be present on the fourth node. R4 is when the pods on the fourth node are ¾ of an inch long. A pictorial chart is available on the web: http://extension.missouri.edu/mississippi/soybeanlinks.shtml
Disease pressure has been low. I did find some frogeye leaf spot in a field over the weekend. Frogeye leaf spot is a disease that can be identified by the circular brown spots on the upper leaves. The other disease I have seen in the area is downy mildew which can be identified by irregular yellow spots on the upper leaf surface and cottony tufts of fungal growth on the underside of leaves.
Soybean rust: Just released on the soybean rust website is the following report: Soybean Rust has been found for the first time this year in Arkansas in Little River County, which is in the southwestern corner of the state bordering Texas. In 2007, rust has been reported in five counties in Alabama (one soybean), 10 counties in Florida (one soybean), five counties in Georgia (all kudzu), six parishes in Louisiana (five soybean), one county in Mississippi (kudzu) and Arkansas (soybean), and 15 counties in Texas (fourteen soybean). Weather conditions have been favorable for rust development in parts of the south and soybean rust monitoring continues throughout the soybean growing areas. Updates on the current status of rust can be found on the web: http://www.sbrusa.net/
Soybean insect pressure has been low so far this season. I have found some stink bugs adults and nymphs along the river. I also found one soybean pod worm in the sweep net. Continue to monitor for insect pressure as we move into August and pods begin to develop. Stink bug thresholds are 2 per 3 foot of row (less than 1 per foot) when visually inspecting plants. Sweep net thresholds are 12 per 100 sweeps. Japanese beetles continue to feed, especially along edges bordering corn fields that had high numbers earlier. Keep in mind that Japanese beetles are part of a larger complex of leaf feeding insects. Threshold for leaf feeding insects is when defoliation has reached 20%.
Jeff House, New Madrid County:
Insect pressure in soybeans is low at this time. Continue to regularly scout your soybean fields for insect pests. Also consider that if your sub- threshold on several different insect pests but due to the different insect complexes out there an insecticide application may be warranted due to combined damage.
Keep in mind, any insecticides that are going out or have already gone out may not protect against any potential late emerging podworm and stinkbug outbreaks in the upcoming weeks as corn begins to dry down. Bean leaf beetle populations are still low at this time in most locations but that too may change as the season progresses.
Fungicides are currently being applied in the area. To determine the timing necessary for a fungicide application, isolate a soybean plant, find the top most node and count down 4 nodes with the top node being one. If you have small pods 3/16 to a ¼ inch long 4 nodes down it is considered R-3 and the time is appropriate to spray. There is a little bit of lee way with this timing, but the timing has proven to have success. Remember that fungicides are best put out as a preventative rather than a curative. While a fungicide program has shown yield enhancement, it is best on fields with high yield potential, low yield potential fields generally do not respond significantly. Also earlier planted beans seem to perform better with a fungicide/insecticide program than later planted beans, including wheat field beans.
The grain sorghum crop looks really good this year and it actually surprised me how much was planted this year. I have not had any reports of midge or head worms needing to be sprayed in grain sorghum. Continue scouting on a regular basis for sorghum head worm. Keep in mind, the sorghum head worm, corn earworm, soybean podworm and the cotton bollworm are all the same insect.
NOW is the time to scout your soybean and milo fields. Scouting early is essential for reducing yield loss and obtaining better control of your target pest, especially when the target is podworm or sorghum headworm.
7/2/2007
Wheat:
Wheat harvest is complete in most parts of Missouri. Much like the variability of the freeze, range of yield was wide across the region. Now that harvest is complete questions may arise about seed wheat. There are few things to consider when deciding on whether to keep wheat for seed.
1) Test weight is the first indication of good seed wheat. The greater the test weight the greater the amount of nutrients to supply to a developing embryo. This year test weight on average was low. With variability in the test weight consider purchasing certified seed. If seed wheat is kept, proper cleaning and a germination test will be necessary.
2) Consider the fact that all the wheat in the area went through a freeze. The most susceptible part of the plant is the anther. The anther produces pollen. If anther numbers were decreased the potential for seed with viable germ could be decreased. If you plan to have seed wheat, a germination test should be done this year. Missouri's state seed testing lab is located in Jefferson City. The lab offers germination testing year round. There is a free period window which runs from June 1 to August 31. Contact an extension center if you need help with preparing and sending a germination test. Keep in mind there is a dormancy period of approximately 4 weeks that wheat must go through before it will germinate. Therefore, do not rush a germination test because the results will not represent the sample.
Preliminary yield data is beginning to appear across southern universities. You can access variety testing information through the county website: http://extension.missouri.edu/mississippi/ag.shtml
Soybeans:
The early planted indeterminate varieties are blooming in the area. The third reproductive stage (R3) is when 3/16 inch pods are present 4 nodes down from the top of the main stem. A pictorial guide for soybean stages is on the web through the county website: http://extension.missouri.edu/mississippi/soybeanlinks.shtml. Continue to monitor for leaf feeders. In general the leaf feeding complex of insects include: Japanese beetles, green clover worms, loopers, bean leaf beetles, blister beetles, woollybear caterpillars and grass hoppers. A combination of these pests are usually present. Threshold is set around 25% defoliation for this complex of insects.
No rust as of last week in the area. Samples are being sent weekly to the lab for analysis. There have been some new finds in Louisiana. You can monitor rust movement at the county website: http://extension.missouri.edu/mississippi/soybeanrustlinks.shtml.
Corn:
Corn in the area has tasseled and for the most part pollination is complete. Once the tassel is fully emerged pollination occurs over a course of 7 to 14 days which is hopefully in sync with silk emergence. Silks do not all emerge at once since this is natures way of insuring at least one set of viable seed. Once pollination is complete silk clipping is no longer an issue. Monitor for second generation corn borer. I had a trap count of 22 moths over the last 7 days. Continue to monitor non-Bt fields for eggs and/or larvae.
The most important management in corn now is water. From pollination through milk stages corn will consume 0.35 inches of water per day. Add this to the water holding capacity of your soil type which will range from 1 to 2 inches for sand to clay, respectively. Rain has fallen over a majority of corn fields. Rainfall events more than the holding capacity of your soil type is excess. If you are using an irrigation scheduling tool the excess is not counted when making an irrigation decision.6/7/07
Wheat:
There have been numerous challenges to this seasons wheat crop. As you begin harvest, monitor for harvest losses. Approximately 20 seeds/square foot is equal to 1 bushel per acre. This may vary slightly depending on seed size and kernel weight. Some fields may be marked for early harvest with plans to bin dry. A good reference for both harvest loss monitoring and bin drying is the University of Kentucky's wheat publication located at the following site: http://www.ca.uky.edu/agc/pubs/id/id125/10.htm
Corn:
Tasseling will begin soon and now is the time to begin scouting for disease on lower leaves. There are numerous considerations when dealing with disease management and every year is different and unpredictable. Keep in mind that not every field may economically benefit from a fungicide application. When making a decision to apply a fungicide consider the factors needed for disease development.
1) The first factor is presence of inoculum on residue or disease on lower leaves. Fungi overwinter on residue while rusts move in from the south. Our biggest fungal disease threat every year is gray leaf spot followed by northern corn leaf blight. They are not the only ones but they are more common across more acres. If you are growing corn after corn (especially no-till) the chance of more inoculum being present in that particular field is higher. However, these diseases are wind blown so infection can occur even in a rotated field so you should also monitor for presence of disease on lower leaves.
2) The second factor is host susceptibility to a disease. If the corn variety in a particular field has a below average to average rating for common diseases such as gray leaf spot then the chance for infection and yield loss will be higher than if the variety is resistant.
3) The third factor to consider is the unpredictable environment. The common leaf diseases need high humidity and/or extended periods of leaf wetness. This may be more of a predictable factor with overhead irrigation.
4) Consider your location and field history. This may not be primary factor for disease development but does tie into all three previous factors. Some areas are prone to more disease development and history could help in the decision process.
In summary, factors that may warrant a fungicide application in a field are: corn after corn, varietals' response to disease, extended periods of leaf wetness via weather and/or overhead irrigation, and crop value. If you do decide to apply a fungicide, research indicates the ideal timing is tasseling. Data suggests missing this timing may reduce or negate overall benefit from an application. Below are a couple articles from Ohio State and Mississippi State Universities that outline the use of fungicides in corn.
http://corn.osu.edu/story.php?setissueID=180&storyID=1083
http://www.msstate.edu/dept/drec/news/2007/corn/corn_disease.pdf
Japanese beetles are beginning to emerge. The concentration seems to heaviest along Highway 77 area in Mississippi County. This area extends from Alfalfa Center/Wyatt to Wolf Island/Doreena. Japanese beetle economic damage occurs when significant silk clipping occurs during pollination. Threshold is the average of three beetles per ear during pollination and before silks are clipped to 0.5 to 0.75 inch above husks.
Southwestern Corn Borer first generation moth flight was 82 moths in 6 nights on June 4. Will check again Monday June 10. You can monitor trapping data for the region of numerous insects by linking to the county webpage and clicking on insect trapping data: http://extension.missouri.edu/mississippi/ag.shtml.
Soybeans:
I have had some questions about soybean stand and planting dates. Replant decisions involve several factors. They include: 1) Determine the cause of the sparse stand. 2) Determine the stand density and condition of the stand. 3) Determine the yield potential of the sparse stand. 4) Estimate the expected gross revenue from the sparse stand. 5) Estimate the cost to replant. 6) Estimate the yield potential and gross revenue from a replanted stand. 7) Determine whether or not the decision to replant pays for itself. Help with these decisions have been outlined in a MU guide sheet: https://extension.missouri.edu/explore/agguides/crops/g04091.htm. Research from Missouri and surrounding states indicate that full yield potential can be accomplished at emerged soybean plant populations of 100,000 regardless of row spacing. A uniform final stand of between 80,000 and 60,000 plants can return 90% or better yield potential. However, keep in mind there are other decision factors and plant populations this low should not be a target. Adjust seeding rates to at least 150,000 seeds per acre.
Jeff House, Regional Agronomist in New Madrid County, has seen a build up of thrips in soybeans in areas due to dry conditions. Hopefully the recent rain was widespread which will eliminate this pressure. Continue scouting soybeans as we progress through the vegetative stages. Scouting should intensify as we enter reproductive stages.
Rust scouting has begun in Missouri. Rust levels have remained low and isolated to kudzu in Louisiana, Texas and Florida. We will continue to monitor fields through the growing season. You can keep track of rust movement at the following website: http://www.sbrusa.net/.
To maximize yields in the early part of the season, be sure to eliminate weed pressure early. Soybeans can tolerate some pressure up to approximately 4 weeks after emergence. If applications are delayed until 6 weeks after emergence yield reduction will begin and the amount will depend on weed density.
5/16/2007
Mississippi County
Wheat:
Wheat ranges from entering milk to entering soft dough stages in the area. There have been some concerns with armyworm numbers. The numbers have been high in pockets. Thoroughly scouting a field is the best way to identify a problem. By now most wheat that had threshold numbers (4 worms/square foot) have been treated. Continue to monitor fields that had a large percentage of freeze damaged stems as they dry down for potential lodging. After the winds yesterday afternoon that came in with the storm the wheat held up well throughout the county, which is a positive sign.
Corn:
Corn is entering the rapid growth stage which begins at the 6th leaf collar or V6 and goes through tassel or VT. This period of time the nodal root system is the primary root system and corn plants are accumulating a large percentage of nutrients that are available. Nitrogen demand jumps from less than 10% uptake prior to V6 to over 60% uptake during this rapid growth phase. During this growth phase key components of yield potential are being set and stress from nutrients deficiency should be avoided. Continue to monitor the crop for signs of deficiency. Corn will respond to nitrogen through tasseling. If you plan to fertigate be sure to have the last nitrogen application out just prior to tasseling.
Water demand also increases during this time period. If you have irrigation it would be beneficial to use an irrigation scheduling tool. Irrigating by visual crop signs is an easy way to fall behind on water demand by the crop. Once behind it is difficult to catch up during the heat of summer. Both University of Missouri and Arkansas have scheduling tools that can be found on the internet. Missouri's is at the following link: http://agebb.missouri.edu/irrigate/woodruff/
Southwestern corn borer and Japanese beetle traps have been set out. Monitor for threshold levels of first generation Southwestern corn borer which are typically emerging in late May through June. Threshold levels are when 25% of plants have egg masses or larvae present with damage to the whorl. Typically, second generation southwestern corn borer cause the most economic loss due to stalk boring. Monitor in July for second generation egg masses or larvae present on 25% of plants. Japanese beetles also emerge in June and will feed primarily on corn silks. Last season, Japanese beetle emergence was around mid-June. Monitor for silk feeding especially in fields along the river. Threshold is 3 or more beetles present on silks and corn is still pollinating.
I looked a corn field today that had symptoms of nematode damage. I sent a sample off to confirm or rule out these symptoms. Unfortunately, there is no nematicide labeled for corn postemergence. Field sampling the year prior to planting will give an idea of nematode pressure. Using a nematicide at planting will help.
Soybeans:
Soybean planting continues. Monitor fields for bean leaf beetles. Threshold for seedling beans is 5 beetles per foot of row or if 1 plant per foot of row is destroyed and beetles are still present.
Soybean rust monitoring will begin in the state. The recent confirmation of soybean rust in Louisiana was on kudzu. Information on rust monitoring can be observed at the following site: http://www.sbrusa.net/
Jeff House, Agronomist, University of Missouri - New Madrid County:
There have been some reports of armyworms showing up in wheat. I have looked at several fields in New Madrid co. and they range from none to very few. This does NOT mean that there aren't some hot spots out there. The best time to look is close to sundown, when they become most active. Very early in the morning is another good time. They go deep into the canopy during the heat of the day. Watch for head clipping. All a worm has to do is take one bite and the stalk will be weakened. If your wheat is in dough stage, then I think the flag leaf function is over with and trying to protect it probably won't pay any returns, BUT I have never seen freeze damaged wheat like this before either. Some fields aren't as far along either, and the flag leaf is still contributing to the yield potential, but this varies on a field by field basis and these fields seem to be in the minority now. Armyworms of this species are primarily grass feeders, so there isn't a concern about them leaving the wheat and going for broadleaf crops, BUT they can get tough on corn and milo as well as rice, so be watching for that too. Smaller plants will be at risk more than larger plants.
There has also been a couple reports of bean leaf beetles (BLB) injuring young beans. While not a common occurrence it does happen occasionally. Watch for damage, and if you have significant damage with BLB present then a pyrethroid application is warranted. They are usually worse this time of year along edges of woods and woody drainage ditches, traditional over wintering areas for them. Sometimes a border spray application can head them off early, but this requires diligent scouting to know how far they have infiltrated into a field.
Also a few cotton fields have been treated for cutworms. This is very isolated at this time, but as with all crop injury aspects, the only way to tell is to either scout the field yourself or hire a scout. Fields with a lot of weeds present or wheat planted as a cover crop will be at greater risk.
4/23/2007
Wheat:
The wheat is still a debate. Some fields are a complete loss and are showing signs of the damage to the lower stem and the flag leaf and the head. Some fields still look ok with green plants and green heads. The level of damage in these type fields is hard to pinpoint. I have looked at several green heads under the dissecting scope and the anthers appear to be healthy. I have peeled back shriveled whitish heads that are not viable in the same fields as green heads. Every field I have been in has had some level of damage.
Evaluating a field, I look for healthy flag leaves, healthy stems and a healthy green head. In some fields the flag leaf was out and tip burn is evident. In those same fields the stalk has brown discoloration and brittle. In some fields the flag leaf shows no sign of burn but stems are still brittle. Stem brittleness is a concern as the wheat matures. Lodging can be a problem and worse if brittleness interrupts water flow which will influence seed fill.
Questions about fungicides are out and about. My recommendation is to wait and see if a viable head emerges. With many potential losses from freeze damage on multiple levels, I would continue to be patient before investing more in the wheat crop. Keep in mind fungicides are designed to prevent disease from destroying leaf area on the flag leaf. Conditions must be conducive for disease development in the upper part of the canopy. Disease in the lower canopy may not move to the upper canopy. If a field is being considered for fungicide applications, many of the common fungicides are labeled up to Feekes 10.5 in Missouri. Feekes 10.5 is when the anthers (male flowers) completely emerge. Check the labeling of your particular product for details on application timing cutoffs.
Corn:
I have looked at several fields of corn over the last two weeks. Many of the questions regarding corn are coming to a close as warm weather has helped the plants that have survived to start showing up above the soil surface. Many replant decisions were still being debated on some late March planted fields and a couple of fields that I observed last Friday were showing signs of recovery. Unfortunately many of the early March planted fields did not have an adequate uniform stand to justify keeping in the month of April.
If one was holding out for greenup, evaluate stands by measuring rows throughout the field. The 1/1000th acre measurement is based on row width. The two common row widths are 38" and 30". Measure 13 feet 9 inches for 38 inch rows and 17 feet 5 inches for 30 inch rows. 22 plants or more uniformly across the field have the potential for full yield. 18 to 22 is on average within 15% of yield.
I have heard several reasons or symptoms of injured corn that were used to justify a replant. I have had questions about the corn root system. The corn root system goes through two phases. The first phase is the seminal (radical) root system which is a primary root system up until V3-V4. The second phase is the nodal root system which starts at the growing point of VE corn which is the junction where the mesocotyl (seed stem) and coleoptile (seed leaf) begin which is above the seed. If you dig up a one leaf corn plant you will observe the beginning development of nodal roots. The nodal roots will become the root system by V6.
With the freeze and replant and potential rain delays, one concern that I was asked the end of last week was when is the latest corn can be planted. Unfortunately there is no magic cut off date and corn development is a function of not only planting date but weather and geographic location. The reason behind planting windows or dates is trying to maximize growing degree days which leads to maturity. Ideally you want enough growing degree days between planting and the hottest part of the season so tasseling and silking will be synchronized. Any stress including heat just prior to and at VT (vegetative tasseling) will cause delayed silk emergence therefore causing a reduction in kernel fill.
Corn growth and development only occurs during the temperature range of 50-86 F. This is why mild weather and cool nights help with corn yield potential because of more growth and development and more efficient pollination occurs. Therefore planting late in the season will affect yield, but it is uncertain how much because of the temperature/weather factor.
Studies out of the Delta Center have shown that late planted corn has a gradual reduction in yield potential as planting progresses further into May. Based on average weather in Southeast Missouri, corn planted on May 10 has a potential yield decrease of 10-15%. After that date yield potential continues to decline at a more rapid pace. The decision to continue planting is ultimately up to the producer. Corn will continue to grow and produce grain regardless of date, however other factors will greatly influence yield potential, in particular weather, disease, and insects.
4/10/2007
http://extension.missouri.edu/mississippi/ag.shtml
Wheat:
Below is a copy of this past weekends highs and lows at the Mississippi County Weather station located at the airport. Minimum (Min) air temperature fell below 28 degrees two nights in a row. This type of weather pattern is new to everyone I have talked with and no research that I know of has been done on sustained freezing of grains. I can only go on research done on single freeze situations that indicate 28 degrees or lower will cause moderate to severe damage to developing heads. Symptoms are difficult to identify early on. The biggest threat is fatal damage to the male flowers (anthers) which are most sensitive to freezing. If the freeze was severe enough to damage leaf and stem tissue then one could expect damage to the anthers. How much damage is the big question. I believe the damage did occur based on the stage and temperatures we experienced over an extended period. Given time we will be able to hopefully verify the severity, until then, only approach would be to finish corn planting and wait and see.
What do you do with the field afterwards is the next question. Some may believe they can utilize the nitrogen they put out on the wheat for corn. Unfortunately, wheat takes up nitrogen from jointing to head emergence. This means that there is no reserve of unused nitrogen in the soil since most wheat was close to heading already. So from a nitrogen stand point you will be starting from scratch if you choose corn. Another question is related to what wheat herbicides were applied and when. Many products have a 2 month or longer rotation restriction for corn. I don't know how big a concern that is for southeast MO compared to northern MO, but it is something I would think about before planting a $100+ bag of corn seed. On specific products, contact an industry representative for more information. One other concern is residue management. There is a large amount of carbon in the wheat fields and that over time will be broken down and nitrogen is the fuel to break it down. So how much of the N you apply for corn will be tied up breaking down wheat straw? One option I would lean more towards is early soybeans since that still fits the rotation and will give more time for the straw to break down before planting.
Date / Max/ Min/ Humidy/soiltemp/
| 4 6 44.7 28.7 54.2 45.3 8.9 17.05 0.00 11.73 | |||||
| 4 7 42.7 26.2 43.5 45.9 7.4 26.25 0.00 11.73 | |||||
| 4 8 48.9 26.2 49.4 49.2 5.0 26.25 0.00 11.73 |
Corn:
Only time will tell. Cool wet conditions, if we get the rain called for will delay regrowth. How much of the stand was lost at the various sizes of corn? Planting depth will be factor since we sustained a string of freezing temperatures. The 4-5 leaf corn was more susceptible to the cold since freezing temperatures were at the soil level or just below. Growing points just below or at the soil line could have sustained more damage and stand loss. I believe in a few days we can determine if the growing point will rebound or not. Determining a percentage of damage will require a thorough walk through the field and pulling several plants and in time taking stand counts. Some of the plants I looked at yesterday and today were mixed. I found some with a nice healthy turgid growing point, I found some that were yellowish with the potential for rebound and I found some that were reddish brown and very watery. I believe patience is necessary before making a decision to drop in and replant. My concern for hasty replanting is if one just drops in and replants and within 2 weeks we finally get regrowth then you have a mess of new corn and regrowth corn. Dr. Wiebold discusses more on corn development in the following:
Dr. Bill Wiebold, State Extension Agronomist, MU Columbia
Normally we would not be too concerned abut freeze damage to small corn plants because the growing point is below the soil surface. Unfortunately, I don’t think these are normal times.
I believe that the temperature was cold enough long enough to have at least some freezing into the soil – at least in some portions of the state. As you know it is the temperature at the growing point region that is most critical in determining corn plant survival. If you don’t mind, let me review some corn emergence events to help us understand the fate of our corn plants.
As soon as the corn kernel is placed in the soil (assuming moisture is available) it begins to absorb water. For the first day or two it does not matter if it is alive or dead, either way it absorbs water. After the kernel absorbs enough water to be about 35% moisture, the embryo “wakes up” and begins all of its life processes including respiration and cell division. The radical emerges from the kernel and grows downward. Two structures emerge and grow upward. The coleoptile is a modified leaf. The mesocotyl is the first stem internode. Both of these structures elongate. The coleoptile is attached to the top of the mesocotyl and the growing point is inside the coleoptile and at the tip of the mesocotyl. The mesocotyl will continue to elongate until the coleoptile is pushed above the soil surface. With normal planting depth the mesocotyl stops about ¾” to 1” below the soil surface. So this where the growing point will be when the corn plant emerges (spiking). If the planting depth is shallow the growing point may be closer to the soil surface.
For the next several weeks the stem elongates only slowly or not at all, but the growing point is rapidly making new cells and initiating the stem nodes and internodes. The growing point stays below ground until about V5 or V6. This means that the visible portion of the plant is leaf blades and leaf sheaths. The leaf sheaths are sometimes called a pseudostem, but they are not stems.
Different modes of damage might produce different outcomes. Mechanical leaf removal such as grazing or hail will likely cause the least permanent damage. Typically the weather conditions are conducive to regrowth and yield loss will be very small even at the V4 or V5 stage.
Freeze damage is a different story and much harder to predict. Remember that by the time the plant has 2 or 3 leaves, all of the stored energy in the kernel has been expended. So, plant survival is very much dependent on producing new leaf surface as fast as possible. The worse scenario is killing temperatures followed by cool, cloudy weather. Clouds reduce photosynthesis and cool temperatures slow leaf growth. If the adverse conditions continue long enough, the plant runs out of energy and dies – even if it should have survived.
This recent weather event may have been cold enough and long enough to have the soil surface freeze. Remember, the growing point is close to the soil surface so frost only ½” depth could damage the growing point in some instances. Splitting the stem and observing the growing point is the only way to predict plant death and that may underestimate the problem if growing conditions remain poor for new leaf growth. The corn growing point is almost white and should be firm. Dark coloration and a watery appearance are not good.
For damage to both wheat and corn, patience is essential. We need some heat units for damage symptoms to express. I know farmers are anxious and have gotten in the habit of planting early. I’ve produced very good corn yields with late May plantings in central Missouri. I do not have planting date data for SE Missouri, but I believe there is still time.
Jeff House, Extension Agronomist New Madrid County, reminded me of something I meant to include in the original message. Corn seed of hot hybrids for replanting or planting into killed wheat may not be available. Farmers may have to accept their fourth or worse choices. I’m not wise enough to estimate the yield effect from growing these less desirable hybrids. It may be only a few percentage points, but it may me more substantial. This is another reason for farmers to slow done and allow the damage symptoms to express (or not).
Finally, short season corn hybrids almost always yield less than their adapted counterparts. In other words in central Missouri, a 97 RM hybrid will usually yield less than a 112-114 RM hybrid. This relationship held even when we planted in late May to early June. We did not factor in drying costs, but again, caution farmers not to jump to an early maturing hybrid if they decide to replant.
Dr. Andy Kendig, State Weed Extension Specialist
Burndown and freeze on weeds:
The weed freeze question of the day is if this cold snap might affect burndown efficacy.
The answer is “it depends”
HOWEVER, I think it would be wise to hold off spraying any glyphosate for 7 to 10 days.
“The test” is fairly simple- look for signs of active growth- THEN it’s ok to spray.
Two years ago, we had a test that we were spraying every two weeks, and there was one spray date (right after an especially cold cold-snap) where glyphosate did almost nothing….The cold weather ITSELF does not really affect glyphosate (though it does SLOW it); however, this freeze after extra warm weather is very likely to “turn things upside down”
I would also lay off of Ignite, it requires the plants to be actively growing.
4/5/2007
Freeze warnings are being issued for this weekend. I have received several concerned calls about what will happen to the wheat and corn. The following is some information describing what could happen to both crops at the stages of development we are in currently.
Wheat:
Wheat development is variable throughout the region. Wheat is well past jointing and most of the wheat heads are 5 to 10 inches up the stem with the flag leaf emerging. Some of the wheat is at Feekes 9 around Charleston. Some wheat is at Feekes 10 which is booting to first part of head is visible. Yes, some areas have heading wheat as well. So, wheat development is variable throughout the region.
The temperature for severe damage is 28 degrees F for most of the wheat in the area that is between Feekes 9 and 10. The amount of damage is dependent on length of time the temperature stays at or below 28 degrees. University of Kentucky indicates that temperatures must be sustained for a minimum time of 2 hours to cause damage. The longer past this time the more potential for damage. If wheat is heading (Feekes 10.1 to 10.5), temperatures falling below 30 degrees F can cause severe damage to wheat.
Some symptoms from freeze damage can be observed shortly after the freeze event others may take some time. For wheat in the boot stage of development the spike can become trapped in the boot causing it not to emerge properly. Careful observation of the head inside the boot may reveal white and shriveled anthers (male flower parts). Healthy anthers are green and turgid (full of water). Since wheat is primarily self pollinated floret sterility will result in poor kernel set and poor yield. Heading wheat will have similar results from a freeze although it does not take as cold of temperatures to cause sterility. Other visual symptoms will be white awns and/or yellow heads instead of usual green color. Below the head you can find a frost ring which can cause the head to snap over on windy days as the head matures.
How much damage occurs depends on many factors from growth stage, length of time at or below 28 degrees, topography, soil moisture, stand density, cloud cover, and wind. Given some time a decision to keep the crop or destroy will be made. If you decide to destroy the crop keep in mind the plant back restrictions of wheat products such as Harmony Xtra and Osprey or Olympus Flex especially if considering corn. If you have specific questions on a particular product contact your local extension office or a product representative.
On the county website you find more information on freeze damage and wheat:
http://extension.missouri.edu/mississippi/wheatlinks.shtmlCorn:
Much like wheat, corn is at various stages of development throughout the region. Corn that has not emerged will be insulated from the freeze since rarely is the air temperature sustained long enough to freeze the ground. Normally, plant cells can tolerate freezing temperatures. However, at 28 degrees F or below ice crystals will begin to develop destroying above ground tissue. The first few weeks of development, the growing point is below ground which protects corn from VE to V4 (4 leaf) from complete loss. Corn that is from VE (spiking) through V2 (2 leaf) can sustain a freeze of all tissue and rebound because seed reserves are still plentiful. Corn that is V3 - V4 should still be able to recover from a freeze especially if the freeze does not destroy all of the green tissue. If all green tissue is destroyed, seed reserves are more questionable and the potential for complete stand recovery may be more variable. However, in many cases corn yield potential is not compromised on V4 or earlier plants. As corn moves into later phases of development the growing point moves to the soil line or above. At this point corn is most vulnerable to a freeze. If the growing point is killed the corn will not recover.
Assessment of freeze damage should NOT be done immediately after the freeze event since it will take time for tissues to either completely die and/or begin to recover. For small corn evaluate corn stands after regrowth begins, which may take several days of warm weather, to determine how many plants are going to recover. One potential problem with freeze damaged tissue is the tendency of leaves sticking together (buggy whipping), preventing new leaves from emerging easily, especially on larger plants. Some growers may consider clipping dead tissue. On small plants (VE-V4) clipping equipment will not work. On larger plants research indicates that clipping does not help and if done to low to the ground could damage the growing point.
More information on freeze assessment can be found on the corn links at the county website:
http://extension.missouri.edu/mississippi/cornlinks.shtmlDavid Dunn
Soil Testing Lab, Delta Center
There have been some questions coming into the Delta Center about nitrogen management in destroyed wheat fields:
Nitrogen considerations for the cold snap
With the projected cold temperatures for the next couple of nights producers are asking what to do if my wheat is adversely affected. If I need to destroy my wheat how much of the expensive nitrogen that was applied in February and March would be available for a corn crop. The last time we had a late cold snap was March of 2008. The question about residual N came up then. We ran a bunch of NO3 + NH4 soil tests on frost damaged wheat ground. The results were variable, but most people were disappointed with the amount of N found in the soil. Most of the N uptake had already taken place. The wheat had done a good job of getting the N from the soil, stock piling it in leaves and stems. This N would have been used to produce grain. The situation would be worse this time around with the freeze coming later in the season and following warmer than average March.
My recommendation then and now was if the wheat is to be abandoned not to worry about how much N is present in the soil now. Go ahead and plant the replacement corn crop. Apply starter N (50-100 lbs) and let the corn grow off. When it is 12-18 inches tall collect soil samples (12 inches deep). We have good numbers on how much N as NO3 needs to be in the top foot of soil to maximize corn yields. My research shows that there needs to be 100 lbs N as NO3 in the top foot for maximum corn yields.
3/30/2007
Corn stands:
Corn planting is well underway. Warm March temperatures brought soil temperatures up above 55 degrees relatively early, although I would estimate growers on an average are only 4 - 8 days ahead of when planting began in 2006. Corn emergence is a function of soil temperature and moisture. Warmer soil temps equals more rapid emergence which increases the potential for uniform stands. Typical emergence rates for corn is around 7 days plus or minus. If conditions turn cold, emergence can be delayed a few weeks and is compounded by extremes in soil moisture both dry and wet. In either case of ideal emergence or delayed emergence evaluate your stand quickly. Get out and take stand counts. The sooner you have an idea of your stand the sooner you can make decision if problems with stand arise.
University of Missouri has a guide on replant decisions and a worksheet to help make those decisions which can be found at
http://extension.missouri.edu/xplor/agguides/crops/g04091.htm. To determine plants per acre, count corn seedlings in a length of row which corresponds to your row spacing and multiply by 1000. The following table has measurements for common row spacing.| Row Space |
38 |
36 |
30 |
20 |
| 1/1000th A | 13 ft 9 in | 14 ft 6 in | 17 ft 5 in | 26 ft 1 in |
Corn fertilizer:
Corn fertilizer is a significant investment and the hope is a high rate of return in corn yield. Protecting that investment and getting the most out of nitrogen should be high on the list of corn management. Many growers in the area utilize two common sources of fertilizer Urea and Urea-ammonium nitrate (UAN) solution, primarily due to the availability of these products. When applying these products under warm moist conditions keep in mind the volatility of these products. If broadcasting UAN into heavy residue, also keep in mind the adsorption into residue which results in unavailability to the crop. UAN is 50% urea, so incorporation is just as critical as with dry urea. Urea is susceptible to volatility due to urease activity on the soil surface converting urea to ammonia gas. Once incorporated by a significant rain event or cultivation, volatility for the most part is halted. As temperatures move above 50 degrees the volatility rate increases. With temperatures in the mid-70 to 80 range the rate of volatility can be rapid and quite high. With rain in the forecast this weekend the incorporation will occur, if rain does not occur watering in or cultivating in your urea source nitrogen may be necessary to avoid loosing too much of your investment. If you are putting out urea, urease inhibitors are one option that will give you a little more time before volatilization occurs. If you have applied urea and it has remained on the surface for several days make plans to monitor that field closely at sidedressing time to possibly compensate for any loss of nitrogen.
Wheat:
Wheat is moving rapidly into stem elongation. At this time maximum rate of nitrogen uptake is occurring as the plant prepares to move into reproductive phase of development. There is some wheat that has some discoloration at the base of the plant. Possible culprits this time of year are barley yellow dwarf, wheat soilborne mosaic or wheat streak mosaic viruses. These viruses will cause stunting in the field as well as reduce nutrient uptake. The only way to confirm a virus is through lab analysis. University of Missouri's diagnostic lab can perform such a test. If wheat is uniform in height and a pale green color the potential problem could be sulfur deficiency. Without sulfur wheat can not convert nitrate into a usable form in the plant. Applying more nitrogen will not correct a sulfur deficient plant.
Wheat aphids are still out in fields. In many cases, once wheat enters rapid elongation aphid numbers usually are not high enough to cause economic loss due to increased leaf material also managing for barley yellow dwarf should be addressed early fall and/or early spring.
2/26/2007
Wheat:
Spring green-up is here and uptake of nitrogen has begun. If you have not had a chance to evaluate your wheat, time is running short. Jointing will begin shortly which a critical time for nitrogen demand. A decision to keep a field needs to be made to invest more money into the crop via crop protection chemicals for weeds and aphids and nitrogen and sulfur fertilizer. Ideally you should have approximately 25 to 35 main plants plus 2-3 tillers per square foot for good yield potential. Anything less is a judgment call. Fewer wheat plants can compensate with more tillers, however, tiller yield in general is not equivalent to main plant yield so fewer plants will result in lower yields. This is why it is important to get a good fall stand of main plants. There is also a point where yield will level off regardless of stand density, at which point it will end up costing more than helping. Remember there are numerous factors to consider. The following is link to Mississippi County's wheat website: http://muextension.missouri.edu/mississippi/wheatlinks.shtml The University of Kentucky's Cultural Practices link indicates that fall stands of 15 to 18 main plants per square foot is approximately 75% yield.
Avoid Sulfur Deficiencies in Wheat
David Dunn, Soils Testing Lab, University of Missouri-Delta Center
Each spring I get several calls about wheat that won’t green up. The first thing that comes to mind is Nitrogen (N). In recent years more and more “yellow” wheat can not be explained by N. What you are seeing might be Sulfur (S) deficiency.
Sulfur deficiency in wheat looks similar to N deficiency, a closer look however shows some differences. Both S and N deficiencies produce stunted, light yellow green plants. Unlike N, S is not highly mobile in plants. Accordingly S deficiency is first expressed in the younger leaves while N deficiency first appears in older leaves. Other symptoms of S deficiency in wheat include shorter, thinner and woody stems, delayed maturity, and reduced grain fill. Commonly S deficiency will occur in a spotty pattern in the field. Proper identification of the problem is critical as excessive N fertilization can induce S deficiency. Adding more N will not help your wheat if S is the problem. Plant tissue testing offers a method for diagnosing S and N deficiency. For best results collect 15 to 20 plants each from both a good and bad area of your field. It is a good idea to also collect soil samples from the same areas of the field.
In previous years sulfur was delivered free to the farm by rain. Volcanoes and fossil fuel burning power plants release millions of tons of S annually. This sulfur was then brought to earth with rain and snow. While the government can not regulate volcanoes the EPA has restricted Sulfur emissions from fossil fuels. S deficiencies in crops have increased each year.
Most of the Sulfur in soil is contained in soil organic matter. This sulfur is made available to plants by bacterial action. Soil bacteria increase in numbers and activity as the temperature goes up. As wheat grows in the spring before the soil warms up it is particularly susceptible to S deficiency. A cool wet spring has the greatest potential for sulfur deficiency to develop in wheat. The lighter-sandy or silt-loam soils of Southeast Missouri are also prone to low sulfur conditions. Regular soil testing is a good way to head off potential sulfur problems. These problems are easily corrected by adding Sulfur fertilizers.
Ammonium sulfate is a commonly available sulfur fertilizer. It is 24%S and 21%N. When applying green up Nitrogen consider including 50 lbs. ammonium sulfate per acre. This will give you 12 lbs./acre of S. Ammonium sulfate is more expensive in terms of N than urea or ammonium nitrate, but when you consider the sulfur the cost is more reasonable. When I compared a mix of ammonium sulfate + urea to urea alone, adding the 12 lbs. of S costs an additional $1.00/acre. This is inexpensive insurance against sulfur deficiency.
Corn:
Corn planting is coming up soon. Just a couple of reminders. If you are planning on using terbufos (Counter) in-furrow insecticide remember that ALS chemistry can not be used. Some of the commonly used chemistry are nicosulfuron (Accent) and nicosulfuron + rimsulfuron (Steadfast). For full list of ALS products consult with your dealer or herbicide rep. If you have the ability to irrigate you will insure better yield if you follow an irrigation schedule. Also keep in mind that longer maturity means longer irrigation requirements. Don’t cut the water off too soon. For further information on corn, visit the Mississippi County website: http://muextension.missouri.edu/mississippi/cornlinks.shtml
Soybean:
When soybean season roles around consider seed treatments. If anything at least consider fungicide seed treatments to help insure a plant stand. We will again be monitoring for soybean rust. I was able to see rust on soybean leaves late last season. In field identification with a hand lens early enough to protect yield will be impossible. If you can easily find rust in the field your yield has been lost. Leaves will be collected in the region and sent to a central lab for analysis. Early detection is critical. For further information on varieties, root knot nematode varieties and other topics visit the Mississippi County website: http://muextension.missouri.edu/mississippi/soybeanlinks.shtml
Jeff House, MU Extension, New Madrid County
Aphid populations increased in some wheat fields in December, with some fields needing spraying. Almost 100% of the fields that needed treatment were early planted fields and had a lot of growth on them, we found none on later planted wheat. Aphids transmit BYDV to the wheat, and this can lead to yield reductions. Most of the yield reductions from BYDV I have seen in the past couple of growing seasons I believe have been from spring infestation of aphids, and if a grower has a field that has been a field with BYDV problems in the past then they really need to be scouting for aphids and making an insecticide application if aphids are present.
One more topic we need to cover is marestail, or as some people call it horseweed. Roundup or glyphosate resistant marestail was rampant last year in a lot of fields in Southeast Missouri. The best control measure we have at this time is a mid March application of Clarity or 2,4-D. This has shown some fairly consistent results, and mid March has shown to be the best timing. A lot of SeMo fields will be worked pretty heavily this spring due to harvest rutting and tillage will take out small marestail, but I have seen large marestail get laid down by a disk, even cut in half and it came back to haunt us. This weed can be controlled but it takes an active approach and timings and weed size are fairly critical. We can still control it with some other chemistries later in the season, but the results can be expensive, hit or miss and may not give the results that an early application of herbicide or tillage can give. Once again a farmer needs to get out in his fields and evaluate the weed spectrum.
Jeff also mentioned in an email that he caught a flight of cutworms on 2/20/07. No-till corn fields need most attention.
University of Missouri Extension
January - February Update
1/31/2007
Private Applicator Training in Mississippi County
Those private applicators whose license expires in 2007 and are interested in recertifying or wish to be certified, there will be two trainings Tuesday, February 13th, at the Mississippi County Library located in Charleston. The event at the library will occur at 8:30 am and 1:30 pm; you only have to attend one. Since your last recertification, the MO Department of Ag has made recertification the same process as certification. The training will take about 80 minutes. Space at the library is limited so please call the extension office to register for a time. If this day does not work for your schedule please call the extension office to arrange for training in the office. The assigned times in the office will be 9:00 am and 2:00 pm Tuesday, Wednesday and Thursday of each week. The office schedule is subject to change and office space is limited so, PLEASE call.
University of Missouri Agriculture Extension
Meetings in the Southeast Region
Pesticide Private Applicator Training in Scott County
If your Pesticide Private Applicator License expires in 2007, you need to attend a training session to recertify. Contact your county Extension office to find out when they will be conducting the training session in your county.
The training sessions in Scott county will be held every Monday morning in February at 8:00 a.m. at the Scott County Extension office. The training session consists of viewing a Private Applicator Training Video that lasts approximately 70 minutes.
If you can not attend one of these training sessions, contact our office at 545-3516 to set up a time to view the video during our regular office hours of 8:00 a.m. to 5:00 p.m.
If you have farm employees or other members of your farm business who need a pesticide private applicator license, they can also attend the training session.
2007 Northern Missouri Regional Cotton Conference
Date: February 9, 2007
Time: 8:45 a.m. - 12:00 p.m., Registration 8:15 a.m.
Location: The Clinton Building, Sikeston, MO
Contact Jeff House, 573-748-5531, Andrea Phillips, 573-379-5431, or
David Reinbott, 573-545-3516 for more information.
Missouri Cotton Production & Outlook Conference
Date: February 13, 2007
Time: 8:45 a.m. - 12:00 p.m., Registration 8:15 a.m.
Location: American Legion Building, Kennett, MO
Contact Mike Milam, 573-888-4722 or Andrea Phillips, 573-379-5431 for
more information.
Agriculture Tourism Conference
Date: February 27, 2007
Time: 5:00 p.m. - 8:00 p.m. (Dinner at 6:30 p.m.)
Location: Elderland Cafe, Bloomfield, MO
1/4 mile north of the 4 way stop on Highway 25 in Bloomfield
Registration: $10 per person, collected at the door.
Contact Van Ayers (573-568-2261) to register or for more information.
2007 Missouri Rice Producers Conference
Date: February 28, 2007
Location: Eagles Club, Dexter, MO
Contact Bruce Beck (573-686-8064) or David Guethle (573-568-2261) for
more information.
Wheat Management
Most wheat planted this fall did not get off to a great start due to weather, primarily rain. Much of the wheat was planted later than normal. Fortunately we did experience a warm December and some warm days in January. I have received some questions on wheat vernalization requirements due to the late planting and warm winter. Wheat only needs to accumulate approximately 15 days of below freezing temperatures to trigger reproduction, all of which do not need to be consecutive.
If your wheat is thin a green-up application should be considered to stimulate tiller production. Typically the time period between green-up and jointing is long enough to produce one tiller. The green-up application will also stimulate the main stem and those tillers present, which will improve their health and potential of producing grain. Time fertilizer applications around a forecast of 50 degree weather, since this is the average temperature at which wheat will take up nitrogen. Fertilizers containing sulfur, such as ammonium sulfate or 28-0-0-6, should be part of the fertilizer program since sulfur is necessary for wheat to convert nitrate into a usable form in the plant. However, if you plan to make only one application, wheat nitrogen requirements are highest at internode elongation, so a single application should be made close to jointing.
Grain Marketing Commentary
David Reinbott
Agriculture Business Specialist
University of Missouri Extension
January 30, 2007
Corn –
Below is a link to my supply and demand projects for 2007-08. An 8 million acre increase in corn acres and demand at 12.5 billion bushels results in ending stocks below 800 million bushels with a yield of 160 bushels per acres. At 10 million acres, it will take a yield of 156 bushels per acre to keep ending stocks in the 800 million bushel range.
http://outreach.missouri.edu/seregion/Corn_S&D_2007-2008.htmTechnically, both the March and December futures contracts have initial resistance at their contract highs of $4.20 and $4.03, respectively. Price support will be at the top and bottom of the price gap at $3.96 and $3.80 in the March contract, and $3.88 and $3.75 in the December contract.
To meet present cash flow needs, I would be making old crop sales. For the new crop, I would target the March through June period for sales. The need for more acres and top yields should give even better pricing opportunities this spring and early summer.
Soybeans –
While the ending stocks of corn continue to decline, soybean ending
stocks continue to edge upward. Ending stocks of 575 million bushels is
a record and in a non-ethanol corn environment, it would have resulted
in soybean prices in the $3 and $4 price range.
Below is a link to my projected 2007-08 supply and demand tables for soybeans. A 6 million acre decrease in soybean acres and demand at 3.145 billion bushels results in ending stocks below 400 million bushels with a yield of 43 bushels per acre. At 8 million less acres, a yield of 43 bushels per acre would drop ending stocks below 300 million bushels.
http://outreach.missouri.edu/seregion/Soybeans_S&D_2007-2008.htmTechnically, initial resistance is at the contract highs of $7.28 in the March contract, and $7.80 in the November contract. The market may try to test the gaps left in the past price rally. In the March contract, the price gap is between $6.95 and $6.78 and in the November contract; the price gap is between $7.45 and $7.25.
For cash flow purposes, I would be making old crop sales. For new crop, I would be targeting the March through June period to make the majority of your sales.
At this time, the soybean crop looks good in South America. While production in South America has been down to steady the past 3 – 4 years, this year’s production should be up. Therefore, if you are less than 1/3 sold on new crop soybeans, I would recommend scaling up to this level over the next few weeks and then target this spring and summer for the remainder of your sales.
Wheat –
Wheat prices benefited by a short hard red winter crop last year in the United States, and an El Nino drought in Australia that cut their production by 50%. In response to higher prices, the winter wheat seedings in the United States are projected to be up 9% for 2007. This should result in increased ending stocks for 2007-08.
Technically, July wheat futures contact has resistance at $5.00 and $5.08 and support at $4.60. With the strength in the corn market, it should help support the wheat market. I would target the March – June time period to make additional sales.
|
|
||||
 |
University of Missouri Extension Mississippi County mississippico@missouri.edu Updated 05/24/04 |
 |
||