Crop Watch, March 7, 2003 <p>

University of Nebraska Institute of Agriculture and Natural Resources Cooperative Extension

Standing residue captures snowy moisture and a lone windmill breaks the horizon in a corn field in eastern Nebraska.

March 7, 2003

Winter Wheat: Assessing stands and potential yields; Controlling winter annuals; Spring fertilization; Blocking wind erosion with emergency tillage
Corn: Resistance management for new YieldGard Rootworm corn; Bt corn and European corn borer: Resistance management and compliance
Drought/Management: State offers hay and forage hotline; Understanding the prevented planting indemnity; Feb. 14 Market Journal addresses drought, crop insurance issues; Farm mediation clinics
Soil fertility: Fertility issues in a dry year: Sample soils and fertilize accordingly; NU fertilizer resources; NRDs receive approval to regulate fertilizer rates
Pesticides: State pesticide regulations revised for 2003; NDA warns of pesticide solicitors
Agricultural News: Farmers should visit with crop insurance agent for 2003 decisions; Livestock producers urged to protect pastures, reduce grazing; Recommended replacement feed and forage alternatives; Frequently asked questions; Declining farm numbers: A long-term reality; Report: Farm numbers decline; Missouri River reservoirs could sink to record lows; Discovering the secret to how organic matter enriches soil; Pearl millet: A new U.S. crop?

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Assessing winter wheat stands and potential yields

Soil moisture may be the most limiting factor in rainfed winter wheat production this year in Nebraska.

Winter wheat seasonal water use varies widely due to weather conditions, but generally it needs 16 to 24 inches. If we use a midpoint of 20 inches, water use would be 4 inches from emergence to start of spring growth, 4 inches from start of spring growth to jointing, 2 inches from jointing to boot, 2.4 inches from boot to flower, 3 inches from flower to milk, 1.6 inches from milk to dough, and 3 inches from dough to maturity. Normally it takes about 7 inches of water to get yield. For each inch of water above that, yield increases an average of 6.5 bushels.

This year's dry conditions are expected to contribute to crown and root disease since dry soil warms up and cools down six time faster than moist soil. This alternating freezing and thawing will diminish the health of the wheat plant, damaging stands and decreasing yields.

Estimating wheat yields early

Wheat growers are frequently confronted with the need to estimate wheat yields in the spring to decide whether recropping is necessary. Determining a reasonable estimate of wheat yield allows growers to predict if it is in their best interest to destroy the wheat and plant a summer crop or leave the wheat for harvest. With little soil moisture in many areas of the state, the chances of being successful with a spring crop are limited. Before making such a decision, growers should be aware of any restrictions imposed by government programs, crop insurance, or previous herbicide use.

Several methods can be used to estimate winter wheat yield potential. I will discuss two, both of which rely on several assumptions that may not be accurate for every season or situation. These assumptions presume that plants are healthy, soil moisture and nutrients are adequate, and that weeds, insects and disease are not affecting yields. Added to the uncertainty of yield estimates is wheat's ability to compensate for changes in the environment.

Method 1

Table 1 is easy to use; however, it relies on several assumptions required to make a yield estimate in the fall or early spring prior to extensive tillering or stem elongation. These assumptions include:

that the wheat plants, on average, develop about five heads;
that each head, on average, develops about 22 kernels; and
that there are an average of 16,000 kernels per pound.

Late-planted wheat and wheat seeds that do not germinate until later because of dry conditions will tiller less and have fewer heads.

To use Table 1, count the number of plants per foot of row. It is best to use at least 5 feet of row in at least five sites within the field and calculate the average number of plants per foot of row. If the stands are uneven, for example the stand is better or worse in the wheel tracks, make sure your percentage of samples in these areas accurately represents the proportion of these areas in the whole field. Locate the column in the table that corresponds to your average number of plants per foot of row and then move down that column until it intersects with the row corresponding to your row spacing. This is your estimated yield.

Method 2

Table 2 was developed using data collected from 1994 to 1998 as part of the Nebraska Wheat Quality Tour. These tours were conducted near May 1, prior to head emergence in most of the state. Factors such as heavy weed/disease/insect infestations or inadequate soil moisture at the time of the tour may suggest fewer final heads and a lower yield potential than indicated in the table. In addition, the table becomes unreliable in situations of extremely low or extremely high tiller counts, or in years when crop development as of May 1 is well ahead or behind normal. For later season yield estimates, yield predictions can be made by substituting the actual number of heads per foot for tillers per foot.

To use Table 2, count the number of tillers per foot of row. Again, it is best to use at least 5 feet of row in at least five sites within the field and calculate the average number of plants per foot of row. Be sure sample sites are representative of the field. Locate the column in the table that corresponds to your average number of tillers per foot of row and then move down that column until it intersects with the row corresponding to your row spacing. This is the estimated yield. Although these multipliers may appear to be in error - everyone knows that wheat fields in the semi-arid Panhandle usually yield less than fields to the east - on a per head basis the multiplier is correct. Wheat fields in the sub-humid portions of the state produce more heads/acre, but typically fewer kernels/head than in the Panhandle.

For example, if your winter wheat field is in southwest Nebraska and you have an average of 30 tillers per foot of row, and your row spacing is 10 inches, multiply the table results of 40 bushels/acre by 0.9 to get a yield estimate of 36 bushels/acre.

Robert Klein
Extension Cropping Systems Specialist
West Central REC

Table 1. Estimated wheat yield potential.

Number of plants/foot of row

Row Spacing 1 2 3 4 5 6 7 8 9 10 11 12

--inches-- --bushels/acre--

6.0 10 20 30 40 50 60 - - - - - -

7.5 8 16 24 32 40 48 56 64 - - -

9.0 7 13 20 27 33 40 47 54 60 - - -

10.0 6 12 18 24 30 36 42 48 54 60 - -

12.0 5 10 15 20 25 30 35 40 45 50 55 60

14.0 4 9 13 17 21 26 30 34 39 43 47 52

Table 2. Estimating winter wheat yield after stem elongation for the Nebraska Panhandle.*

Number of tillers/foot of row

Row spacing 10 15 20 25 30 35 40 45 50 55 60 65

--inches-- --bushels/acre--

6.0 22 34 49 56 67 79 90 101 112 - - -

7.5 18 27 36 45 54 63 72 81 90 99 118 --

9.0 15 22 30 37 45 52 60 67 75 82 90 97

10.0 13 20 27 34 40 47 54 61 67 74 81 88

12.0 11 17 22 28 34 39 45 51 56 62 67 73

14.0 10 14 19 24 29 34 38 43 48 53 58 63

*The table was developed using data collected in the Nebraska Panhandle. For other Nebraska locations, multiply the yield in the table by the following factor: southwest Nebraska - 0.9; central and south central Nebraska -- 0.85; southeast Nebraska - 0.75.

Controlling winter annuals in winter wheat

Winter annual weeds cause both direct and indirect winter wheat losses. They are very competitive with winter wheat throughout the growing season. Additionally, some winter annual grass weeds also result in dockage and/or foreign material discounts when contaminated grain is delivered to the elevator. In order to minimize losses, growers must control these weeds in a timely manner.

Broadleaf weeds

Common broadleaf winter annual weeds in winter wheat include blue mustard, tansy mustard, tumble mustard, field pennycress, and shepherd's-purse. Unfortunately, many growers are unaware of these weeds in their fields until the weeds start to bloom in spring. By this time, control is difficult and most of the crop damage has already occurred. To be effective, winter annual broadleaf weeds need to be controlled in the late winter or very early spring, before stems begin to elongate and plants begin to bolt.

Blue mustard may be the most difficult to control because it bolts very early. To be effective, herbicides typically need to be applied to blue mustard in late February or early March. 2,4-D applied in early April usually will provide excellent control of tansy mustard and the other winter annual broadleaf weeds, but only fair control of blue mustard. Adding a sulfonylurea herbicide, such as Ally or Amber, to 2,4-D will improve control, particularly after these plants have bolted; however, it may not help increase yield because the weeds have already used soil moisture and nutrients. If the sulfonylurea herbicide is used after bolting, but prior to seed production, it may help reduce the amount of seed produced.

The bottom line is that winter wheat growers need to scout their fields in the late fall or winter to determine if control of winter annual broadleaf weeds is needed. In the case of blue mustard, herbicides should be applied in late February or early March. The other winter annual broadleaf weeds should be treated in late March or early April. Once the plants are flowering, it is probably too late to treat. If timed correctly, 2,4-D (8 oz/acre of LV4 ester or 16 oz/acre of 4 lb/gal amine) provides low-cost and effective control of these weeds. Wheat should have at least four tillers before applying 2,4-D or serious crop injury may occur.

Grass weeds

Only in the last few years has it been possible to selectively control some of the winter annual grass weeds, such as downy brome, jointed goatgrass, or feral rye, in winter wheat. Although control is often best when herbicides are applied in the fall, some spring control is possible. Maverick Pro^� provides selective control of downy brome and other Bromus species in winter wheat. Maverick Pro should be applied at a rate of 2/3 ounce of product per acre in 5 to 20 gallons of water per acre. A non-ionic surfactant should be added to postemergence treatments at 0.5% on a volume basis. Spring applications to downy brome have been more inconsistent than fall applications. Occasionally spring control is as high as 85%, but more typically it ranges from 35% to 70%. Usually these plants are significantly stunted, but will produce seed. Precipitation following application appears to be important for improved herbicide activity. Growers should be aware of the rotation restrictions with this product.

A few Nebraska growers planted Clearfield^� wheat varieties last fall. These fields can be treated with Beyond^TM herbicide this spring to control downy brome, jointed goatgrass, and certain broadleaf weeds. Although spring applications of Beyond have provided poor control of feral rye, spring applications have provided excellent control of jointed goatgrass and downy brome when treated with 4 ounces of product per acre. Apply the herbicide as soon as active spring crop growth begins. Postemergence applications require adding a surfactant at 0.25% and a nitrogen fertilizer solution of 1 to 2.5% on a volume basis. (One percent on a volume basis is one gallon in 100 gallons of spray solution.)

If winter annual weeds are a regular problem in your winter wheat, change the crop rotation. Including a spring-seeded crop such as corn, sorghum, soybean, oat, proso millet, or sunflower in the rotation with winter wheat-fallow provides an additional year in which to prevent seed production and allows the soil seed bank to gradually decrease.

Additional information on weed control in winter wheat is available in the Wheat Production Systems Handbook, which is available on the Web at the Panhandle Research and Extension Center Home Page at: http://www.panhandle.unl.edu

Drew Lyon
Extension Dryland Crops Specialist
Panhandle REC

Table 1 shows the nitrogen recommendations (lbs N/acre) for wheat for various nitrogen and wheat prices at several soil nitrate concentrations.

Residual nitrate-N Wheat price per bushel

$2.50 $3.50

Fertilizer price per pound of nitrogen

Average ppm in 3 ft. 0.20 0.25 0.30 0.20 0.25 0.30

Nitrogen rate (lbs N/acre)

1 102 87 73 118 108 98

2 91 77 62 108 97 87

3 81 66 52 97 87 77

4 70 56 41 87 76 66

5 60 45 31 76 66 55

6 49 35 20 66 55 45

7 38 24 9 55 45 34

8 28 13 0 44 34 24

9 17 3 0 34 24 13

10 7 0 0 23 13 3

11 0 0 0 13 2 0

12 0 0 0 2 0 0

Spring nitrogen fertilization of winter wheat

Most winter wheat grown in Nebraska requires additional nitrogen fertilizer for profitable production. This is true for virtually all soils in Nebraska where wheat is commonly grown unless there is a large carryover of fertilizer nitrogen. Due to dry conditions in 2002, there is potential for higher than normal residual soil nitrate levels. Residual fertilizer nitrogen can be measured effectively with a residual soil nitrate test of the root zone.

While the depth of the root zone is often six feet or more for wheat, most available nitrogen affecting yield is in the top two to three feet of soil. Sample to a depth of three feet to determine residual nitrate levels. Samples taken from less than three feet deep will be slightly less accurate. (See NebGuide: Guidelines for Soil Sampling, G91-1000 for a comprehensive overview of soil sampling recommendations.) If a soil analysis is not available, use the recommendations for 9 ppm of nitrate-N per acre, which represents an average or medium soil nitrate level.

Topdressing nitrogen on wheat in spring allows the producer to avoid potential yield depression associated with fall nitrogen applications. It also allows for the evaluation of yield potential based on stands and soil moisture. Topdressing in the spring provides a significant advantage to wheat producers because it can help them avoid investing in a crop with a low yield potential. Topdressing should be completed by April 15 or prior to jointing. Wheat grain yields generally decrease and grain protein increases as a result of later nitrogen applications.

The optimum nitrogen rate (lbs N/acre) for winter wheat (with a maximum rate of 100 lbs N/acre for dryland, and 150 lbs N/acre for irrigated) is calculated using the following equation:

((N PRICE / WHEAT PRICE) + 0.014558 x NO3-N - 0.235) / -0.00138

Where,

-- N PRICE is the price of nitrogen fertilizer in dollars per pound

-- WHEAT PRICE is the price of wheat in dollars per bushel

-- NO₃-N is the average ppm nitrate-N in the top three feet of soil.

All fertilizer nitrogen sources -- ammonium nitrate (33-0-0); urea (45-0-0); urea-ammonium- nitrate UAN (28-0-0); and anhydrous ammonia (82-0-0) -- are generally effective for spring nitrogen fertilization. Ammonium nitrate is preferred for topdressing when incorporation is impossible because it is the least susceptible to loss from volatilization. If the nitrogen fertilizers are incorporated soon after application, all nitrogen sources should be equally effective. Base your fertilizer selection on the most economical source of nitrogen that fits the restrictions of the particular wheat production system you use.

David Tarkalson
Soil Fertility and Nutrient Management Specialist
West Central Research and Extension Center
Donald Sander
Professor Emeritus
Department of Agronomy and Horticulture

Using emergency tillage to stop wind erosion in wheat

The drought conditions in western Nebraska have resulted in weakened winter wheat stands that are prone to further damage by blowing soil. Surface soil in many wheat fields has become smooth, dry, and finely granulated and is very susceptible to wind erosion.

Earlier attempts at stopping the blowing soil have been ineffective in some areas because the dry soil conditions have not been conducive to bringing soil clods to the soil surface. Recent snows and cold conditions may have improved this situation and there may now be a window of opportunity for growers to use emergency tillage to prevent further stand loss from blowing soil. It's better to control damage early rather than risk losing the entire crop.

Tillage can be used as an emergency measure to stop wind erosion in growing wheat. Use an implement with narrow chisel or shovel point shanks spaced four to six feet apart and drive perpendicular to the direction of the prevalent winds.

The purpose of emergency tillage is to provide a rough, ridged, cloddy surface that will be more resistant to wind erosion. Surface roughness reduces wind velocity at the soil surface and helps trap windblown soil particles. Where possible, use emergency tillage before soil blowing starts. Soil erodes more rapidly from abrasion by wind blown soil particles than from wind that contains no soil particles.

If erosion is anticipated because high winds are forecast, start emergency tillage on areas in the field most vulnerable to erosion before the wind reaches a critical speed. If soil conditions are too dry to form clods, crop residues, such as hay, straw, or corn stalks, or livestock manure may be used to prevent blowing from starting in vulnerable areas. Crop residues usually need to be anchored in place with a stubble puncher or a disk with gangs set at minimum angle and shallow depth. Approximately 2,000 to 4,000 pounds of residue or 6 to 8 tons of livestock manure are required per acre to control erosion on vulnerable spots or in areas where erosion has begun. If soil blowing has already started, begin emergency tillage on the upwind edge of the eroding area.

The most effective method would be to till in a direction perpendicular to the expected wind direction but at an angle to the wheat row to minimize the number of wheat plants destroyed. Field speed for emergency tillage will depend on the implement, soil conditions, and depth of tillage. In general, slow speeds will produce more clods, while faster speeds will provide more ridging. Speeds of 3 to 4 mph usually result in the most effective surface. For best results, vary the face angle of the tillage tool, depth of operation, and field speed to obtain maximum overall roughness.

Use narrow chisel points spaced 4 to 6 feet apart and run them 4 to 6 inches deep. Some farmers will use a 3-foot spacing between chisel points because it is easy to remove two of three gangs and obtain the 3-foot spacing; however, this strategy does not allow the farmer to come back and chisel between previous ridges if further erosion occurs.

Data from a five-year study at two Kansas sites suggests this type of emergency tillage has minimal effect on potential yield, but can reduce the damage to growing wheat and reduce soil loss in moderate erosion situations. This study found emergency tillage caused the most damage to wheat yields when the wheat had just emerged. The least yield reduction was found when the tillage was done in fields with plants already tillered. Emergency tillage is not effective if clods cannot be brought to the surface, and is not possible after the soil is frozen more than 2 inches deep.

Maintaining residue cover, especially standing residue cover, and using crop strips are very effective ways to reduce the need for emergency tillage to control erosion. However, conditions sometimes occur when serious soil erosion is imminent or has just begun and corrective action is required to protect the soil and growing crops.

Keep a close eye on your fields and take appropriate action as circumstances dictate. For more detailed information on emergency tillage see NebGuide G75-282, Emergency Wind Erosion Control.

Drew Lyon
Extension Dryland Cropping Systems Specialist
Panhandle REC

Understanding the prevented planting indemnity

Crop insurance deadline: March 15

As ag producers prepare for the 2003 planting season and the March 15 deadline for acquiring crop insurance coverage for spring planted crops, the indemnity payment method for prevented planting (PP) acres needs to be clarified. Any prevented planting acres will be eligible for only a percentage (usually 60%) of the insured value. The following example will explain this process. For this example it is assumed that the farm has an actual production history (APH) for irrigated corn of 150 bushels per acre and intends to purchase multi peril crop insurance (MPCI) at the 70% level. The price election for corn is assumed to be $2.20 per bushel. Under this scenario, the calculations for PP indemnity are as follows:

150 bu/acre APH x 70% = 105 bu/acre coverage

105 bu/acre x 60% = 63 bu/acre PP coverage

63 bu/acre PP coverage x $2.20/bu = $138.60/acre PP indemnity

This indemnity level will allow producers to cover the cost of the insurance and the fixed costs associated with the land resource.

(For more information on crop insurance issues this year, see Burgener's story in the Feb. 10 CropWatch.)

Paul Burgener
Extension Ag Economics Research Analyst

Resistance management for new YieldGard Rootworm corn

Recently, the EPA and Monsanto announced the registration of YieldGard Rootworm corn. Do not confuse YieldGard Rootworm corn with YieldGard Corn Borer corn or any other Bt corn hybrids that are resistant to European corn borer. The YieldGard Rootworm corn hybrids contain a coleopteran (beetle)-specific Bt protein (Cry3Bb) that is toxic to corn rootworm. They have no effect on corn borers or any other caterpillars.

As with past Bt corn hybrids, insect resistance management (IRM) will be required of farmers who grow YieldGard Rootworm corn. Although the IRM program is similar to those for earlier Bt corns that targeted European corn borer, there are some significant differences. This only makes sense since the biology of the corn rootworm is very different from that of the European corn borer.

The resistance management requirements for YieldGard Rootworm corn are:

Growers must plant a structured refuge of at least 20% non-YieldGard Rootworm corn that may be treated with insecticides as needed to control corn rootworm larvae. Growers will not be permitted to apply insecticides labeled for corn rootworm to the refuge for control of insect pests while adult corn rootworm are present unless the YieldGard Rootworm field is treated similarly. Refuge acres should be planted as blocks in or adjacent to YieldGard Rootworm cornfields or as in-field strips.
External refuges must be planted adjacent to YieldGard Rootworm fields.
When planting the refuge in strips across a field, refuges must be at least six rows wide, preferably 12 consecutive rows wide.
In addition, the refuge must be planted in similar ground as the YieldGard Rootworm corn. If the YieldGard is planted in ground that was in corn the previous year, the refuge must be planted in ground previously planted to corn. General management of the YieldGard Rootworm corn and the refuge should be similar.

We will provide performance data on YieldGard Rootworm corn from UNL trials in a future issue of Crop Watch.

Tom Hunt
Extension Entomology Specialist
Haskell Agricultural Laboratory
Bob Wright
Extension Entomology Specialist
South Central Agricultural Laboratory

Bt corn and European corn borer:
Resistance management and compliance

While producers who grow Bt corn resistant to European corn borer are aware of the associated resistance management requirements, it's always good to review requirements prior to the growing season. I'd also like to address some questions on resistance management compliance.

Resistance management

The resistance management requirements as stated by EPA for 2003 are:

Growers must plant a refuge of at least 20% non-Bt corn that may be treated with insecticides as needed to control lepidopteran (caterpillar) stalk-boring and other pests.
Refuge planting options include: separate fields, blocks within fields (e.g. along the edges or headlands), and strips across the field.
External refuges must be planted within 1/2 mile of the Bt field (1/4 mile or closer preferred).
When planting the refuge in strips across the field, the strips should be at least four rows wide, and preferably six or more rows wide.
Insecticide treatments for control of European corn borer, corn earworm, southwestern corn borer (Cry1Ab or Cry1F corn hybrids) and/or fall armyworm and black cutworm (Cry1F corn hybrids only) may be applied to the refuge only if economic thresholds are reached for one or more target pests. Economic thresholds will be determined using methods recommended by local or regional professionals (e.g. Extension educators, crop consultants). Microbial Bt insecticides (e.g. Dipel) must not be applied to non-Bt corn refuges.

Additional information on Bt corn, European corn borer, and resistance management is available in Resistance Management for European Corn Borer and Bt Transgenic Corn: Refuge Design and Placement, NebFact NF425, also available at your local Cooperative Extension office.

There are several reasons that farmers should comply with resistance management requirements. First, and most important, compliance will slow the development of Bt-resistant corn borers and preserve Bt as an effective pest management tool for the future. Many of us have seen how efficacious Bt corn hybrids are against the European corn borer. Loss of this management tool could mean going back to the days of large-scale spraying and the problems associated with treatment timing, chemical application, etc.

Second, compliance is part of the contractual agreement that a grower is required to sign when buying Bt transgenic corn seed. By doing so, growers state that they are aware of and will comply with resistance management requirements. Specific resistance management information will be a part of each corn seed bag label and must be followed. Failure to comply with the resistance management requirements could result in a grower losing access to the Bt corn hybrids for a year.

And finally, if the EPA feels that compliance is not high enough, it could seek future regulation of Bt corn use.

Compliance

Initially, compliance was measured through the use of grower surveys; however, now random field visits also are conducted to monitor compliance. Responsibility for conducting resistance management monitoring lies with the registrant (e.g. Monsanto), not EPA.

For example, farmers are selected from the pool of farmers who bought YieldGard Corn Borer corn, contacted, and a date is scheduled for a field visit by an independent agent, such as a consultant. Planting records are examined, refuge fields are measured for size and distance from the Bt field, and plants are tested for the expression of the Bt toxin. If found to be significantly out of compliance, the farmer is provided resistance management educational materials, aided in developing a resistance management plan, and revisited the next year. If the farmer is found to be out of compliance the second consecutive year, the farmer will not be able to buy the product the next year.

Tom Hunt
Extension Entomology Specialist
Haskell Agricultural Laboratory

Farm mediation clinics

The farm mediation program sponsored by the Nebraska Department of Agriculture conducts farm mediation clinics at locations throughout Nebraska. The remaining March clinic dates are: March 11, North Platte; March 13, Ainsworth; March 14, Norfolk; March 18, Lexington; and March 26, Norfolk.

The clinics offer individual and confidential information and education on farm finances; the laws, regulations and policies governing the Farm Services Agency (FSA); debt restructuring and other legal options; and how the mediation program can help work with lenders to find an agree-able and workable solution. Contact the Farm Hotline at 800-464-0258 to make an appointment. The contact for the program at the NDA is Marian Beethe at 402-471-6890 or marianjb@agr.state.ne.us

Sample soils and plan accordingly

Fertilizer issues in a dry year

NU fertilizer resources

For more information on NU soil fertility research and recommendations, check the following resources, which are available at local Extension offices or on-line.

Managing Nitrogen Efficiently in Nebraska Crop Production, a Web site at http://cropwatch.unl.edu/focusnitrogen.htm, which includes research and yield reports, downloadable Microsoft Excel files, on-line calculators to estimate nitrogen rates, and two sample chapters from Nutrient Management for Agronomic Crops in Nebraska, EC155.
Guidelines for Soil Sampling, NebGuide G1000, available on-line at http://ianrpubs.unl.edu/soil/g1000.htm
Nebraska Soils Home Study Course, available on-line at http://www.ianr.unl.edu/soilshomestudy/index.htm
Calibrating Anhydrous Ammonia Applicators, EC737, available on-line at http://ianrpubs.unl.edu/farmpower/ec737.htm
Index of Extension publications on soil fertility, available on-line at http://ianrpubs.unl.edu/soil/.

With subsoil moisture significantly below normal across much of Nebraska this spring, producers should carefully consider their fertilization plans for the coming crop season. Fertilizer rates, sources, and application methods all can be potentially influenced by the current dry conditions.

Soil sampling

If producers did not collect subsoil samples for residual nitrate-N last fall, they are strongly encouraged to do so this spring. Sampling done last fall has revealed above average variability in residual nitrate-N. Irrigated corn in much of Nebraska produced near record yields, and thus might have been expected to leave very little residual nitrate-N in the soil. However, we have found that was not always the case. There have been situations where fields were fertilized at moderate rates, produced yields well in excess of 200 bu/acre, and still had high residual nitrate-N after harvest. Decent rains during and immediately after harvest last fall in parts of the state evidently allowed substantial nitrogen mineralization from soil organic matter and subsequent accumulation of nitrate-N. We also have observed very low residual nitrate-N in other fields following very high yields, so residual nitrate-N after irrigated corn is not very predictable. On the other hand, soil residual nitrate-N following dryland corn with extremely low yields last year is usually very high. In many cases, there may be enough residual nitrogen that fertilizer is not needed this year for dryland crops; however, sampling will be required to determine this. For either dryland or irrigated fields it will pay to sample for residual nitrate-N this year.

Realistic expected yield

With currently low subsoil moisture, and poor prospects for significant precipitation to refill the soil moisture profile, producers should adjust their yield expectations for dryland corn or sorghum downward. Even without accounting for residual nitrate-N left from last year, the crop fertilizer requirement for nitrogen will be less for dryland crops due to lower expected yields based on soil moisture.

Moisture conservation

Producers should look for every opportunity to conserve moisture by limiting tillage operations, including fertilizer application. While anhydrous ammonia is normally the least expensive nitrogen fertilizer source, producers should carefully weigh that cost and the resulting loss of moisture incurred during application and compare it with the cost of surface-applied applications which do not cause moisture loss. There are additional tradeoffs, however. Nitrogen fertilizers (either liquid or dry) will typically be less efficient and more subject to volatilization and immobilization than nitrogen fertilizers incorporated into the soil. These processes can be accentuated by larger-than-normal amounts of crop residue this spring, since dry conditions have not allowed as much residue decomposition as usual.

Starter fertilizers

Producers should be cautious when using starter fertilizer with the seed if soil conditions are dry at planting. Fertilizers placed with the seed (primarily nitrogen and potassium fertilizers) are hygroscopic and will draw moisture away from the seed. Excessive rates of starter fertilizer can result in germination damage and stand loss. Placing starter fertilizer in a band a couple of inches away from the seed will minimize the potential for germination damage. More information on starter fertilizer use can be found in the NebGuide, Using Starter Fertilizers for Corn, Grain Sorghum and Soybeans, G361.

Richard Ferguson
Extension Soils Specialist

NRDs receive approval to regulate fertilizer rates

If you'd like to learn more about or follow the progress of a specific legislative bill, visit the Nebraska Legislature's Web site.

A new Nebraska law will allow Natural Resource Districts implementing Ground Water Management Plans to regulate the rate of fertilizer applied. Previously, NRDs were authorized to regulate the timing, but not the rate of application as part of their best management practices program.

The change will affect producers in the Central Platte NRD, which includes about one-half million acres stretching from Kearney to Columbus. Since the Groundwater Management Plan was first implemented in this NRD in 1988, nitrate levels in the water and soil have dropped on approximately 95% of the acres, said Ron Bishop, general manager of the Central Platte NRD.

Producers who were typically applying 200-220 pounds of nitrogen per acre then, now typically apply 145 pounds per acre. On approximately 5% of the acres; however, nitrate levels in the groundwater continue to increase, Bishop said.

The change will be implemented following a one- to two-year period to allow for education and a warning in those areas where rising levels are a problem, Bishop said. Producers in the management area already have their soil and water tested annually for nitrates. The change means that the NRD will consult with the University of Nebraska or a crop advisor certified by the American Society of Agronomy to establish rates based on soil and water nitrate tests.

State pesticide regulations revised for 2003

A number of new state regulations related to pesticides, their application, and their applicators have been enacted and apply to this crop production season. Many of the changes are helping to fine-tune state regulations or bring them in line with federal regulations. Following is a synopsis of some of the changes.

The minimum age for pesticide applicator licensing is 16. Previously state law did not provide a minimum age.
No recommendations can be made that are contrary to or inconsistent with the pesticide label. While this had been specified in federal law, the change provides the Nebraska Department of Agriculture with a legal base for pursuing such infringements. This applies to anyone using or recommending a pesticide, from other producers in the coffee shop to consultants or agribusiness.
NDA created a new category, Wildlife Damage Control (14), to cover the use of General Use Pesticides (GUPs) and Restricted Use Pesticides (RUPs) to control animal pests (rodents, moles, nuisance birds, prairie dogs, coyotes, etc.). As a result, the Agricultural Plant category no longer is applicable to cover animal pest control measures using pesticides. To apply even general use pesticides for animal control, a commercial applicator will need to be certified in this category.
The older combination category of Demonstration and Research/Regulatory has been separated into two new subcategories of 1) Demonstration and Research and 2) Regulatory. Both need to be attached to a parent category such as Ag Plant or Ornamental and Turf. Applicators are "grandfathered" into the new subcategories without additional testing if they select the new subcategories at recertification.
If a manager or supervisor who makes pesticide recommendations in a commercial pesticide applicator business wants to hold a pesticide license, the individual must be licensed as a commercial applicator and can no longer be licensed as a noncommercial applicator. (Last year the state implemented a licensing fee of $90 for commercial pesticide applicators. No license fee is required for noncommercial applicators.)
A noncommercial applicator license is applicable for independent crop consultants who recommend pesticides (GUPs or RUPs) for clients. This would include crop advisors who do not apply restricted use pesticides, yet need state certification to hold membership in a crop advisor association. The noncommercial license is not issued to ag landowners or operators, who need private applicator licenses, or to people making commercial applications for hire.
A commercial applicator in the Ag Plant category can apply restricted use pesticides to agricultural crops on land he/she farms personally.
Any employee of a political subdivision (applying pesticides (GUPs or RUPs) for vector control must obtain certification/licensing prior to applying such pesticides and would be classified as a noncommercial applicator. As an employee, these people are applying pesticides for their employer as a part of their regularly assigned duties.

For more information on these and related topics visit the Pesticide Education Resources Web site or call the Pesticide Education Office at 800-627-7216.

For more information about current regulations, see the NU Extension NebGuide, Pesticide Laws and Regulations, also available at your local Cooperative Extension office.

Larry Schulze
Pesticide Education Specialist

March 14 Market Journal: Adjusting for drought

Guest speakers on the March 14 Market Journal will be addressing some drought-year alternatives to traditional crop, water, and pest control strategies.

Presented by the University of Nebraska Cooperative Extension, Market Journal is an hour-long video program focusing on agricultural risk management and marketing issues. The program is hosted by Doug Jose, NU Extension farm management specialist.

Several segments of the program will highlight western Nebraska issues, focusing in particular on the concerns of farmers facing crucial shortages of both ground and surface water. NU Extension specialists and educators appearing on the program will provide an overview of cropping plans adapted to dry conditions, offer tips on conserving soil moisture, and talk about the most effective and economical methods of pest control. Speakers will include several NU Extension specialists from the Panhandle Research and Extension Center at Scottsbluff, including: David Baltensperger, crop breeding specialist, alternative dryland crops and forages; Paul Burgener, ag economics research analyst, economic considerations of alternative crops; and Dean Yonts, irrigation management in dry conditions. Tom Holman, Scotts Bluff-Morrill Extension educator, will address the economic considerations of alternative crops.

Also on the program will be Al Dutcher, Nebraska state climatologist, with an ag-related, long-range weather forecast; Roy Smith, Plattsmouth producer and crop consultant, discussing trends in the corn and soybean markets; Lynn Lutgen, NU Extension marketing specialist, with an analysis of the wheat market; and Andy Kuhn, ADM, with the merchandiser�s view of grain market conditions and trends.

On March 14, Market Journal can be viewed on the Dish Network�s University House Channel (NAUHS) 9411, at noon Central Time. It also will be broadcast via satellite (NEB*sat channel 102), and the public is invited to view the program at Cooperative Extension offices in the following Nebraska counties: Boone, Cass, Holt, Madison, Saunders, Sioux, Valley, Washington, and York. In Lincoln, Market Journal is available on Time-Warner Cable channel 21. Audio and video clips from the program will be available on the Web at http://marketjournal.unl.edu

State offers hay and forage hotline

According to the National Drought Monitor, much of western Nebraska remains in an extreme drought with much of the rest of the state in a moderate to severe drought. Visit the Drought Mitigation Center Web site, hosted by the University of Nebraska-Lincoln, for further information.

The Nebraska Department of Agriculture is giving a new name to an established resource. The Hay Hotline will now be known as the Hay and Forage Hotline to reflect that all types of forage can be listed on the database, from hay to alfalfa, pasture, bailed cornstalks, and other sources. Also, the database will be updated regularly; postings older than 90 days will be removed. Once removed, hay and forage suppliers can call the Department to be re-entered into the database and provide any updated information.

"According to the Nebraska Agricultural Statistics Service, we entered 2003 with the lowest hay stocks in Nebraska since 1957. We hope the Hay and Forage Hotline can help those in need of forage for livestock connect with those that have it for sale or donation," said Merlyn Carlson, NDA director.

The toll-free hotline number is (800) 422-6692. Producers who have hay, alfalfa, pasture space, or other types of forage to sell or donate may call that number to be included in the database of available supplies.

Those needing forage should call that same number to request a list of sellers. The list will be updated daily as information is available. The service is free and available to all buyers, sellers, and donors.

NDA warns of pesticide solicitors

The Nebraska Department of Agriculture is warning farmers and ranchers to be wary of recent telemarketing sales of farm chemical pesticides. The NDA has received complaints about telemarketers making false claims about the pesticides they are trying to sell.

"In the cases we have been alerted to, the pesticide products have been grossly overpriced, sometimes as much as ten times what the product is really worth," said Merlyn Carlson, NDA director. "You are more assured of getting a credible product at a fair price if you do business with your local pesticide dealer."

If you're contacted by one of these solicitors please contact Rich Reiman of the NDA at (402) 471-2394 or the Nebraska Attorney General's Consumer Protection Division at 800-727-6432.

Briefs and updates

Farm numbers down

Nebraska�s number of farms and ranches declined during 2002. The number of farms and ranches is 52,000, down 1,000 or 2% from 2001, according to a recent report from the USDA Agricultural Statistics Service. The decrease was split between farms with less than and those with more than $100,000 in ag sales. Land in farms and ranches in Nebraska remained unchanged at 46.4 million acres. The average size of operation increased to 892 acres, up 17 acres from a year earlier.

Drought Web site

As the state enters another crop season with most of the state still significantly short of valuable soil moisture, readers can visit the Drought News and Information Web site, sponsored by the NU Institute of Agriculture and Natural Resources, for ongoing updates and recommendations related to crop and livestock production. The site includes news and audio stories and Web links to a variety of other resources related to drought and ag production, weather forecasts and more.

Call for grant proposals

The North Central Region Sustainable Agriculture Research and Education Program is again offering a competitive grant program for producers to research, demonstrate or educate others about profitable, environmentally sound, socially responsible agricultural systems.

Farmers and ranchers can apply for grants of up to $6,000 for individuals and up to $18,000 for groups of three or more interested in investigating any sustainable practice or concept. A total of $400,000 is available for grants.

Producer applicants must live in the 12-state North Central Region comprised of Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota and Wisconsin. Applications are due March 28 and funding is expected in fall 2003. For more information or an application, contact the NCR SARE office at the University of Nebraska in Lincoln by calling 402-472-7081, faxing 402-472-0280 or sending an Email to ncrsare@unl.edu Information is also available on the NCR SARE Web site.

Amber Waves

Amber Waves is a new magazine from the USDA Economic Research Service on "food, farming, natural resources and rural America". Visit the Web site to subscribe on-line to the print or Web version.

Tips on hiring ag help

A new book,�Ag Help Wanted: Guidelines for Managing Agricultural Labor,� was written by a multi-state group of Cooperative Extension specialists to help everyone who manages human resources on farms, ranches, nurseries, dairies, and other agricultural operations. It is organized into six main chapters: Roles and Responsibilities of an Agricultural Employer; Organizational Planning; Staffing the Farm Business; Supervising Agricultural Work; Managing Employee Performance; and Communication and Problem Solving. The book is available as a 242-page soft-cover book with color photos for $25 or on CD-ROM for $10. For more information, visit the book�s promotional Web site.

New disease-resistant soybean

A new soybean released by the Agricultural Research Service has disease resistance and other advantages that make it an ideal candidate for producers who plant early. The cultivar, Freedom, was tested in nearly 50 environments and performed well in different regions. It was particularly well adapted to the clay soils of the lower Mississippi River Valley and eastern Mississippi, where early planting of soybeans has been widely adapted so plants can set and fill pods before hot, dry periods. Freedom was found to be fairly high yielding and disease resistant, maintaining adequate plant height in early season plantings on clay soils, a combination that normally tends to suppress growth. For more information, read a news story about the research on the USDA Web site

Published by The Institute of Agriculture and Natural Resources Cooperative Extension, University of Nebraska-Lincoln, Cooperating with the counties and the U.S. Department of Agriculture

University of Nebraska Cooperative Extension educational programs abide with the non-discrimination policies of the University of Nebraska-Lincoln and the United States Department of Agriculture.

	Published by The Institute of Agriculture and Natural Resources Cooperative Extension, University of Nebraska-Lincoln, Cooperating with the counties and the U.S. Department of Agriculture
University of Nebraska Cooperative Extension educational programs abide with the non-discrimination policies of the University of Nebraska-Lincoln and the United States Department of Agriculture.