Agronomy Notes

April, 2004

Reese and Allison Pillow Named 2004 ASA/DuPont Young Leaders

From left-Tom West (Vice President, Business and Community Support, Pioneer Hi-Bred International), Allison and Reese Pillow.

March 15, 2004: St. Louis, Missouri -- The American Soybean Association and Pioneer, A DuPont Company, are pleased to announce Reese and Allison Pillow of Greenwood, Mississippi have been named 2004 ASA/DuPont Young Leaders. The Pillows were selected from a group of applicants to represent Mississippi in a program involving producer participants from 23 other states and Canada.

The ASA/DuPont Young Leader Program targets soybean farmers who are innovative, assertive, "young in leadership" and looking to make their mark in agriculture. Now entering its 21st year, the program has a tremendous record of success. Hundreds of program alumni have assumed significant leadership responsibilities in state and national soybean associations and promotion boards as well as national, regional, and state agricultural organizations, including Farm Bureau, National Corn Growers Association and more. Nearly all are making a difference in agriculture by ensuring the voice of the American farmer is being heard.

The 2004 class of ASA/DuPont Young Leaders participated in a challenging and educational leadership experience February 29 - March 2, 2004, in Las Vegas, Nevada. This three-day seminar included leadership and issues training, and provided an opportunity for participants to meet and learn from other Young Leaders from around the country. Class members also took part in the Commodity Classic, March 2 - 4, 2004 rounding out a full week of learning, networking, and personal growth. In December 2004, participants will travel to Pioneer's offices in Johnston, Iowa, to complete their training.

Using Forage Quality to Improve The Biological and Economic Efficiency of beef cattle production
by Dr. Richard Watson

Forage quality is an important factor in beef cattle production. Now that I have informed you of this fact, one which you probably already knew, I need to define exactly what I mean by 'quality'. Forage quality can be described as a measure of nutrients (carbon, nitrogen, sulfur, phosphorus, and other minerals) in the plant tissue that are vital for livestock production, and their availability for digestion and ultimate metabolism by the grazing animal. We could also add the aspect palatability, which is a measure of the animal's willingness to eat a particular plant or plant component. Palatability is often linked to nutrient levels and availability, so, for the purposes of this article, we will assume that quality covers all these aspects.

Ultimately, forage quality is summarized in terms of its total digestible nutrients (TDN), i.e. the total fraction of the ingested plant material (not including water) that can be digested and used by the grazing animal. Essentially TDN determines how much of the eaten plant material becomes animal (meat, milk, bone, hide etc.), and how much is deposited back onto the ground as manure. Therefore, the better our TDN, the greater the proportion of plant nutrients that are used to make beef. This is very important, as we get paid for the amount of beef we produce, not the amount of manure.

In addition to improving the partitioning of nutrients (how the animal uses the nutrients), quality also improves the overall forage intake of the animal, thereby increasing the total amount of nutrients ingested by the animal in a given time period. The affects of forage quality on intake are related directly to retention time in the rumen. Rumen microbes break down forages with higher digestibility faster and the resulting products of digestion are available to the animal more quickly. This faster breakdown of plant material allows more forage to be consumed in a given time period, and hence, both the total quantity, and availability of nutrients is greatly improved. The reverse of this is observed when we feed hay to livestock. In general, the TDN of hay is much lower than fresh forage as there is a much higher component of indigestible fiber material. Therefore, the microbes in the rumen take much longer to break down the plant material and extract the nutrients from hay, reducing the throughput and making the animal 'fill-up' so consuming more forage is made difficult. The inability to grow beef cattle on a hay-dominated diet is not so much determined by the nutrient content per say (although very important), but a limitation in the amount of hay that can be consumed and digested in a given time period. This is particularly important for young cattle that need to maintain adequate levels of forage intake to meet the nutritional requirements of growth. Therefore, the better the quality of the forage, the faster young cattle are able to grow. Growing your young cattle fast has a number of benefits. Rapidly growing cattle are more biological efficient as they partition a higher proportion of ingested nutrients into making valuable products (i.e. meat), and less into metabolic functions associated with body maintenance (e.g. thermoregulation). Rapidly growing animals are also more economically efficient as they require less feed to achieve that same weight as an animal growing more slowly. Achieving rapid growth rates can also increase the economic returns of stocker cattle enterprises through improved marketing flexibility with more animals grown to their target weight sooner, and the lowering overhead costs by not having to keep cattle for as long.

Keeping Forage quality up in your pastures
by Dr. Richard Watson

The most important thing to understand when managing your pastures to maintain high forage quality is the relationship between quality and plant maturity. Simply stated, the more mature your pasture gets, the lower the forage quality. This relationship is true for all forage plant species but some species, such as many of the warm season grasses, lose their quality more rapidly than others. For example, as bermudagrass pastures age from four to eight weeks old, they will lose around 10-15% of their TDN due to lignification (formation of woody fiber) of the plant tissue. While this may not sound like a lot, it can mean the difference between animals gaining weight or just holding their weight.

The best way to keep forage quality high is to maintain pastures in a leafy state by controlling the pre and post grazing forage height. Not letting pastures get too long (> 8-10") before grazing, and not grazing them too short (< 3-4") will help keep quality high. This method of control obviously requires some form of limit or rotational grazing to allow the leaf to re-grow.

There will always be times of rapid forage growth that cannot be controlled by the grazing animals. During these times, it is important to limit the excess forage production to one area of the farm that can be shut up for hay, while grazing the remaining area to keep it vegetative and higher quality. Some clipping of pastures may be required to remove reproductive (seed head) growth, which is responsible for a significant reduction in leaf growth and TDN levels.

Incorporating legumes into your pastures can also greatly improve forage quality. Legumes, such as clovers, have high levels of crude protein (>20%) and generally have high TDN levels. Maintaining a legume content of 20-30% in a grass-based pasture is recommended for improving animal performance.

It is a good idea to test your soils and forages each year for their nutrient status to ensure that the many important micronutrients are present in sufficient levels to maintain animal health. This will also help identify fertility requirement of your pastures.

Ultimately, the better condition your pastures are in, the better your animals are going to produce for you. While growing forage tonnage is important, without maintaining the quality, most of this tonnage will be wasted as manure or poor quality hay.

Corn
by Dr. Erick Larson

New Nitrogen Recommendation

MSU will have new, more conservative nitrogen rate recommendation for use on corn this growing season. Growers should apply 1.3 pounds of nitrogen per bushel of yield goal. Nitrogen recommendations for corn in the mid-south are based entirely upon corn yield goal, since little if any nitrogen carryover lasts through the winter due to our wet, relatively warm climate. This new recommendation results from several years of research evaluating nitrogen rates in high-yielding irrigated environments and is not influenced by high nitrogen prices.

Nitrogen Sources and Application

Corn yields may differ drastically depending upon nitrogen fertilizer source and application method. No-tillage research studies in Missouri and Tennessee show N-sol and urea (urea-containing nitrogen sources) broadcast on the soil surface reduced corn yield potential 9-23% compared to ammonium nitrate broadcast, N-sol injected, or anhydrous ammonia injected. This can reduce economic returns from $20-$80 per acre compared to ammonium nitrate or N-sol injected. The urea-containing nitrogen sources reduce corn yield potential because they are subject to volatilization when applied to the soil surface. Surface-applied urea sources readily volatilize when substantial crop residue or vegetation is present on the soil surface, temperatures exceed 55 degrees F, and when rates exceed 100 lbs. N per acre, until rainfall incorporates the nitrogen. Thus, corn producers should minimize or eliminate surface application of N-sol or urea in their fertility program.

Nitrogen Application Timing

Split application of nitrogen fertilizer generally improves corn nitrogen use efficiency. Corn extracts less than 15% of its seasonal nitrogen uptake before rapid vegetative growth begins. Maximum nitrogen use rate occurs just prior to pollination. During early growth stages, considerable nitrogen may be lost due to denitrification and leaching. Therefore, the bulk of a split nitrogen application should be delayed until just prior to rapid vegetative growth. This growth period begins at the V10 growth stage (10th leaf stage) which occurs about 40 days after plant emergence or when plants are about 30 inches tall. The normal nitrogen recommendation specifies applying 1/3 of the total N at planting and applying the remaining N about 30 days later.

Scout Fields

Scout corn for stand, weed and insect problems every 2 to 3 days until corn is about 12 inches tall, and be prepared to take control measures. Insects or weeds may quickly ruin a good stand or become too developed to control. Timely problem identification allows specific treatment selection and application timing, which likely will improve control and lower expenses.

GRAIN SORGHUM
by Dr. Erick Larson

Don't Plant Too Early

Grain sorghum will not germinate at soil temperatures less than 65 degrees F, which will greatly increase likelihood of stand failure. Thus, the optimum planting dates for sorghum are similar to those for cotton: April 20 to May 15. Optimum seeding depth is 1 ? - 1?", rather than a shallower depth at which cotton and soybeans are planted.

Don't Plant Too Much Seed

A final plant population ranging from 40,000 to 70,000 plants per acre should produce optimum grain sorghum grain yields grown in dryland culture. Grain sorghum has tremendous ability to increase yield potential if given favorable environmental conditions, especially if plants are spaced uniform. However, excessive stands compound drought stress, lower stalk quality and increase disease likelihood. Sorghum seeding rate should exceed the population goal by 10 to 20% depending upon seedbed conditions and planting date. This over-planting rate is relatively high because sorghum's seedling vigor is low, compared to corn.

WHEAT
by Dr. Erick Larson

Glyphosate Drift

A considerable number of wheat fields throughout the Delta are showing injury to upper leaves and head that is consistent with off-target glyphosate herbicide drift injury. The abnormal symptoms appear as chlorosis or whitening of leaf tissue, often in an interveinal pattern, generally beginning near the leaf collar extending out towards the leaf tip. Some wheat heads are also often malformed, twisted or bent over when they have difficulty emerging from stunted leaf sheaths in the boot stage. Presence of similiar injury to other grass species outside of the field would help confirm presence of glyphosate drift. Johnsongrass or other relatively immature grass species would be good candidates to observe for potential injury. The extent of grain yield reduction will largely depend upon whether the injury sterilizes reproductive organs. Unfortunately, we will likely need considerable time to completely evaluate the extent of head damage until after flowering and kernel development begins. Of course, chlorosis will limit photosynthetic capacity of the flag leaf, which will cause yield reduction as well, but this will likely be relatively minor, compared to sterility problems.

RICE
by Dr. Tim Walker and Dr. Mark Kurtz

Planting

Approximately 35% of the rice acreage south of highway 82 was planted prior to the rains on March 28 and 29. A limited amount of acreage was also planted north of highway 82. With exceptional soybean prices, high fuel and fertilizer costs, some producers are still pondering the thought of decreasing rice acreage; however, favorable rice prices will keep any decrease to a minimum. Cocodrie will be the primary variety, followed by Priscilla and Clearfield 161. Clearfield XL8 acreage will increase. Wells and Francis will be grown on limited acreage. With this being the inaugural year for Cheniere in Mississippi, growers will be watching this variety very closely. I have spoken with a few growers who are interested in planting Cheniere on newly land-formed silt loam soils. Since Cheniere is new to us, I would not place Cheniere on those soils without draining for straighthead. Cheniere is rated MS-MR for straighthead, and is definitely more resistant than Cocodrie, but I recommend that we evaluate it this year in "real-world" scenarios before we choose not to drain in straight head-conducive environments. The verdict is still out on Francis. For some growers, it produced superior yields, but for some it did not perform well. If you grow Francis on silt loam soils, watch for blast. One method to help minimize this disease is to maintain a flood depth of greater than four inches from about green ring to draining. An additional tool that may decrease the lodging of Francis is to decrease your seeding rate to about 70 lb of seed/acre on well prepared seedbeds.

Fertility

If you have not already done so, you should be preparing to apply nutrients other than N where your soil test recommends it. Phosphorus deficiencies can significantly reduce yields, especially on soils where the pH is above 7.5. If your soil test results are in the low category, you should plan to apply P in the window just prior to planting until 2- to 3-leaf rice. If your soil test P is in the medium range, you will probably not see a yield response to P-fertilizer; however, you should begin applying P on a crop removal basis. This application can be made up to the preflood timing.

Weed Control

The State of Mississippi received a Section 24(c) registration for the application of Command and Commit (clomazone) herbicides by air for the 2004 growing season. Rates range from 1 gallon to 7 acres on medium soils to 1 gallon to 5 acres on fine soils. Command must receive moisture after application for maximum effectiveness. It may be applied from 14 days prior to planting to 7 days after planting, but prior to grass emergence. For control of existing weeds present at the time of application include one of the following post emergence herbicides registered for control of grass weeds in rice. Command may only be tank-mixed with one tank-mix partner among the following herbicides: Aim, Clincher, Duet, Facet, Newpath, Propanil, Regiment, Ricestar, Stam, and SuperWham with either crop oil concentrate or non-ionic surfactant. Do Not Apply With Glyphosate. Do not apply Command in sand, loamy sand, or sandy loam soils. Make sure you follow the Command label when tank-mixing with other herbicides. Some rice growers have experienced compatibility problems while others have not. I have never experienced tank-mix compatibility problems with Command in my research trials. However, error on the side of caution and have plenty of agitation in your spray tank. Use caution when making applications to recently land formed fields. Rice injury may result if cuts are deep and cation exchange capacity (CEC's) is low.

As I write, much of the rice acreage south of Hwy 82 has been planted. With this in mind, I suggest that you use a residual herbicide at planting for grass control because cold weather always comes around Easter and many post emergence herbicides don't work well in cold weather.

If you find yourself in a situation with emerged rice and grass, in cold 55 degree weather, remember Clincher performed well in May 2002 when temperatures dropped into the 40's and day time highs weren't above 65.

SOYBEANS
by Dr. Alan Blaine

Above average temperatures and excellent field conditions allowed a great deal of early planting to take place prior to April 1st. By April 10th, baring a major problem, Mississippi will be well over 50% planted. Given earlier than expected spring weather and higher prices additional acreage has shifted to soybeans. Although planting is not yet complete, soybean acreage may experience an increase as high as 300,000 acres.

All acreage planted early was done so with plans for August delivery. Midsouth producers are the only ones that are in a position to capitalize on early delivery but it is not going to be accomplished on every acre. There are certain criteria that will ensure early harvest and in a previous article I attempted to highlight some planting date guidelines that should help with planting decisions.

Conditions thus far have been excellent, but there are several areas that we must focus on as this growing season begins. First, our planting capacity far exceeds our harvest capacity. As the crop begins to mature it will do so rapidly (August). In order to avoid in-field problems harvest must be timely.

Any damage whether it be due to late season diseases, insects, in field weathering, etc., will occur exponentially. If you do not have adequate harvest capacity, begin working to secure it as soon as possible. For those who have adequate capacity you might want to consider doing some custom work for your neighbors.

Secondly, do not let anything effect maturity of your crop. Allowing insects to abort fruit, inadequate fertility, improper irrigation scheduling, etc., will all impact maturity.

Third, we must give some additional consideration to weed control. Many in an attempt to plant early have planted early maturing varieties in wide rows. Over the last ten years we have seen the growth habit of soybeans change dramatically. We have very few early maturing varieties that will fully canopy on wide rows especially when planted early. In order to obtain the most growth from Group IV's, they must be planted later than mid/late April. This later planting window would limit acres available for August harvest but it would allow for more growth. If you have planted wide row soybeans early be prepared to utilize directed sprays, hooded sprayers or possibly cultivation. Because many of these wide row scenarios will never canopy these options or a residual herbicide program are a must. Do not attempt to continue to spray Roundup over the top. Avoid over the top applications on beans that have begun to pod or after the R2/R3 growth stage, preferably R1(first bloom).

Fourth, do not get in too big a hurry to make post herbicide applications. If you planted early and your burndown or tillage cleaned up the field avoid spraying too early. Wait until summer annuals emerge which will likely be at least late April. Sporadic winter vegetation or even summer annuals that emerge sporadically should not be a major cause for alarm. Treat as needed but wait on your primary flush which will occur once temperatures increase.

I realize that it dried out and moisture became erratic in some fields during planting in late March. I hope you avoided the urge to plant deep in order to place seed into moist soil. When planting early you would be better off to plant dry versus deep. Soil temperatures warm faster at shallow depths.

Another factor is the uncertainty and intensity of rain events prior to May 1st. Over the last few years, we have repeatedly observed early plantings take 2 plus weeks to achieve a stand. Planting in marginal moisture/dry soil under cool conditions is not the same as in June. Germination problems will not occur until soil temperatures exceed 92-94 degrees and this is not a factor in late March/April. I hope replanting is minimal because additional planting seed of the top varieties will not be available. I also have my fingers crossed that everyone avoided the urge to chase moisture early. If you did not let's hope we can avoid any heavy rain event prior to emergence.

With above average prices we need to take care of this crop so we can insure delivery of a quality product early.

Dr. Frank Matta, Interim Department Head
Department of Plant and Soil Sciences
Box 9555
Mississippi State, MS 39762
(662) 325-2701

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