Volume 6, Issue 28                                                                                     October 2, 1998

This will be our last WEEKLY ISSUE of Weekly Crop Update.

We will be putting monthly issues out until next spring. The newsletter will be placed on the web or in the mail the first Friday of each month. This is new and we would appreciate your feedback on the monthly issues.

For those who access Weekly Crop Update via the internet and would like to get an e-mail when the monthly issue is put on the web, please forward your e-mail address to wootten@udel.edu or call 302-856-7303 ext. 312 to be to be added to my e-mail list. Thanks!


Vegetable Diseases - Bob Mulrooney, Extension Plant Patholgist ; bobmul@udel.edu


Based on information supplied by the BASF company, stone fruits and strawberries are to be removed from the Ronilan fungicide label. After this summer, new labels will no longer list these fruits. Effective, June 30, 1999, growers will no longer be able to purchase Ronilan for these fruit uses, and use of Ronilan on these crops will not be allowed after January 30, 2000. In the meantime, it is still legal to use Ronilan on stone fruits and strawberries for the next 18 months; thus, there will be no product recalls.

Delaware growers have used Ronilan for control of strawberry gray mold and peach brown rot diseases. Growers should plan to use their remaining stocks next year. The company emphasizes that Ronilan is still safe and effective when used according to the label. This action is being taken in response to the new requirements of the Food Quality Protection Act (FQPA).

For other crops, the company is also changing the formulation of this fungicide from a flowable Ronilan FL to a solid formulation, Ronilan EG. v

Field Crops

Field Crop Insects - Joanne Whalen, Extension IPM Specialist ; jwhalen@udel.edu

Field Corn.

As you make plans to purchase seed for the 1999 growing season, you may be considering a Bt corn variety. In areas of the state where corn borer pressure was heavy, growers have been very impressed by the level of corn borer control. Bt corn can be an important tool in corn borer management so we want to be sure that this technology maintains its effectiveness. As you make plans to purchase a Bt corn variety, be sure to consider the following points:

  1. Although resistance to be Bt corn has not been documented in the field, 3 laboratories in the USA (one in Delaware) have resistant populations. This tells us that the potential for resistance exists if this technology is not used properly.
  2. As recommended by the NC205 Regional Research Committee looking at resistance management, one of the primary ways to manage corn borer resistance is the use of a refuge of non-Bt corn. This committee is recommending that you plant 20- 30% of your acreage to a non-Bt corn hybrid that acts as a refuge for corn borer moths. More information will be available this fall regarding the use of refuges. Although it was initially thought that we have a number of alternate corn borer hosts in the Mid-Atlantic region, research and surveys in the regions are indicating that this is not the case. Therefore, non-Bt corn appears to be the best choice for a refuge.
  3. Results from economic studies indicate that producers will save more money in the long run by using as large a refuge as possible (at least 20-30% non-Bt corn) which will preserve this technology for a longer period of time. v


Field Crop Diseases - Bob Mulrooney, Extension Plant Patholgist ; bobmul@udel.edu

Charcoal rot or soybean cyst nematode? In the fall, often during harvest, growers see stunted plants in areas of their fields. Two possible causes for this stunting and yield loss could be the soybean cyst nematode (SCN) and/or charcoal rot. There could be other causes as well, but I wanted to focus on distinguishing these two common disease problems.

SCN will cause stunting and when roots of stunted plants are dug there is reduced root mass and cysts can be found in the surrounding soil and on the roots. At this time of year, however, the cysts are very difficult to see without some magnification. Soil sampling is suggested to determine if SCN is the problem.

Control measures include rotation with a non-host crop such as corn, sorghum, or vegetables except snapbeans, and the use of resistant varieties. Resistant soybeans are being evaluated again this year for resistance to SCN at locations near Rising Sun, Laurel, and Greenwood. This work is being supported by the Delaware Soybean Board and check-off money.

Charcoal rot is primarily a root and lower stem disease. Diseased tissue in the taproot and lower stem develops a gray discoloration. Eventually the lower stem is girdled, causing wilting and death. Infected soybeans have many tiny black specks (sclerotia) on the roots and lower stem just beneath the epidermis or bark. The sclerotia resemble a sprinkling of powdered charcoal, hence the name charcoal rot. The disease is most severe when plants are under moisture stress and other stresses such as nutrient deficiencies, compaction, nematodes, or other pathogens. In Delaware, early maturing group IIIs and IVs are the most at risk. Group V varieties usually escape damage from charcoal rot.

To control charcoal rot plant late maturing varieties and reduce plant stress by maintaining healthy vigorous plants. This would include proper fertilization, weed management, nematode control, and irrigation, where possible. v


Weed Management Considerations for Small Grains - Mark VanGessel, Extension Weed Specialist ; mjv@udel.edu

As wheat and barley season quickly approaches just a few reminders for weed control. For no-till small grains consider the usefulness of a burndown herbicide. If the weeds present are summer annuals such as pigweed, lambsquarters, crabgrass etc., a burndown herbicide will have little usefulness. These weeds will die with the first killing frost. However, if you have winter annuals like chickweed in the field, a non-selective herbicide will control them and reduce the weed competition. If you are going to be spraying for perennial weeds, spray Roundup 10 to 14 days before planting. Planting will damage and stress the perennials so you want the Roundup to have plenty of time to translocate. Do not apply Banvel or 2,4-D in the fall prior to planting small grains.

After the crop is planted, the earliest labeled treatment is Harmony Extra at the 2 leaf stage of the small grains. Fall treatments in small grains often are not adequate for full-season control and a second application in the spring is often necessary. Fall treatments are not necessary for broadleaf weeds unless chickweed or other winter annual weed growth is very rapid early in the season. v


Grain Marketing Highlights - Carl German, Extension Crops Marketing Specialist ; clgerman@udel.edu

Corn and Soybean Stocks Up Sharply from 1997; All Wheat Up 15 Percent

Old crop corn stored in all positions on September 1, 1998 is estimated at 1.31 billion bushels, up 48 percent from September 1, 1997. This is more than 3 times the corn stored on September 1, 1996, which was the lowest stocks level on record since 1976. On- farm stocks are up 35 percent from last year, while off-farm stocks are 64 percent above last year's level. Indicated disappearance from all positions for the June-August quarter at 1.73 billion bushels is 7 percent above the same quarter last year.

Old crop soybeans stored in all positions on September 1, 1998 totaled 200 million bushels, up 52 percent from September 1, 1997 and 9 percent above 1996. On-farm stocks are 93 percent higher than this time last year, while off-farm stocks are indicated to be 32 percent above the previous year. Indicated disappearance for September 1997-August 1998 is 8 percent above last year.

All wheat in all storage positions, estimated at 2.38 billion bushels, is up 15 percent from September 1, 1997 and the highest September 1 level since 1990. On-farm stocks are 12 percent higher than a year ago while the off-farm level is 17 percent higher.

The Grain Stocks Report was considered neutral for pricing action for grains, being in line with trade expectations. This means that price isn't expected to change much until export business picks up. For soybeans, September stock estimates came in slightly over the high end of trade expectations and was deemed somewhat bearish.

New Forum Available to Address Grain Marketing Issues

A new electronic forum, the "Grain Marketing Discussion Group" is being offered on a trial basis by the Department of Food and Resource Economics, University of Delaware and is now available on the internet. The purpose of the discussion group is to provide grain & oilseed farmers, merchandisers, traders, analysts, industry representatives, educators and other interested parties a timely forum for addressing important issues and questions regarding grain markets and marketing alternatives. To subscribe, send a message to majordomo@udel.edu with the only text in the body that reads:

subscribe grn-mktdg@udel.edu

After successfully subscribing, you will receive a message from majordomo welcoming you to the grn-mktdg mailing list! The grain marketing discussion group list owner is Carl L. German, Extension Specialist III, Crops Marketing clgerman@udel.edu, phone: 302-831-1317. v


Check for Residual Nitrogen When Planting Small Grains Behind Corn - Gordon Johnson, Extension Agent - Agriculture; gcjohn@udel.edu

When planting small grains behind corn, consideration should be given to the amount of residual nitrogen in the soil that is available to the small grain crop. Considerable residual nitrogen may be available, especially in areas with extended drought conditions where the corn crop was fertilized to achieve a higher yield goal than the actual harvested yield. If adequate residual nitrogen is available, no additional nitrogen will be needed in the fall for small grain establishment.

It is possible to use a soil nitrate test prior to small grain planting to check for residual nitrogen. Analysis of a soil sample taken from the surface 6 inches before planting can indicate adequate fall nitrogen availability. Your county extension office, conservation districts in each county, the University of Delaware Soil Testing Laboratory, and private labs can run quick tests to determine soil nitrate levels. If soil nitrate levels are greater than 60 lbs./acre no additional N fertilizer will be needed for fall establishment under most conditions. Of course, if planting no-till small grains, some surface applied nitrogen may still be necessary as decomposition of stalks may "rob" some nitrogen from the soil surface layer. v


Small Grain Fall Fertilization - Richard W. Taylor, Extension Agronomist ; rtaylor@udel.edu

For planting after corn, Gordon Johnson’s article covered how to determine if enough residual nitrogen remains in the soil so no fall nitrogen will be needed. The same soil nitrate test can be used if planting wheat after potatoes. For soybeans, we use grain yield to estimate if adequate residual soil nitrogen is present to support small grain growth. If soybean yield is below about 30 bu/A, residual soil nitrate levels are probably inadequate. Apply 20 to 30 lbs N/A at or shortly after planting to establish the crop and promote root growth and tiller production. If soybean yield is about 40 bu/A or greater, adequate soil nitrate is present to support fall grain growth.

What about other nutrients? If you are following the small grain crop with soybeans or grain sorghum and fall fertilizer deals are favorable, the potassium (potash) and phosphorus required by the second crop can be applied to the small grain crop in the fall. Be sure to base application rates on a recent soil test. This will help you spend your limited dollars on fertilizer only if it is needed and is likely to increase your net return on investment by boosting crop yields more than the cost of the fertilizer. It is generally accepted that because of the risks involved in growing crops, you should expect to get back 3 to 4 dollars for every dollar spent. Less than that and you are likely to only be changing dollars for dollars and over time you will end up losing dollars. Soil testing and research-based recommendations will also help you in your stewardship of the land and help protect the environment from fertilizer runoff or leaching.

Also, a recent soil test can advise you on the need for lime. Keep in mind that barley is very sensitive to low manganese (Mn) levels when the pH is above 6.0. In fields with low Mn levels or pH’s above 6.0, watch your fields for the first signs of Mn deficiency (poor growth; whitish chlorotic spots between the veins; and, if severe, dying plants). At the first sign of a problem, a soil test or a whole plant tissue test can be used to confirm Mn deficiency and, if confirmed, apply foliar Mn to stimulate growth.

Wheat is also sensitive to low soil levels of Mn and pH’s above 6.4 on heavier soils and 6.2 on lighter soils. In some fields, Mn deficiencies have been seen in the spring when growth resumes and after the first nitrogen application because the soil at a depth of 6 to 12 inches is much higher in pH than the surface plow layer. When problems occur in the spring but the usual soil test does not indicate the pH value is too high, take soil samples from each 4 to 6 inch layer of soil to determine if the deeper soil layers are causing the problem. v


Small Grain Planting - Richard W. Taylor, Extension Agronomist ; rtaylor@udel.edu Bob Uniatowski, Extension Associate - Field Crops; bobuni@udel.edu

In a three year study, we found that barley planted in late-September has about a 10 percent lower yield potential than when planted the first week to 10 days of October. Delaying barley planting until mid-October also reduced yields by 10 percent. Planting in late October reduced yield by another 10 percent. Planting in early November decreased yield potential an additional 20 percent.

Can I Plant late, but Increase my Seeding Rate? We found that it didn't help. Compared with seeding barley at 2 bu/A, increasing the seeding rate up to 3 bu/A did not change yields. This was true with a September planting date as well as a mid-November planting date. In a few years of our four year study, a seeding rate of 1.5 bu/A did reduce yields (by 3 to 5 bu/A) compared to the 2 bu/A rate, but the difference was not significant averaged across years.

For wheat, we found that winter weather conditions significantly impact planting date differences. Ideally, wheat should be planted during the two week period following the Hessian fly-free date for your location. Delayed planting until mid- to late-November decreased yield potential an average of 19 bu/A (about a 25 percent yield reduction). This varied by year as follows: 7.5 bu/A (<10 percent) in 1992, 41 bu/A (50 percent) in 1993 (a very harsh winter), 13.5 bu/A (15 percent) in 1995, 21 bu/A (25 percent) in 1996, and 10.2 bu/A (12 percent) in 1997.

As with barley, increasing the seeding rate with late planted wheat did not increase the yield potential. Seeding rates of 20, 30, or 40 seeds per row foot on 7 inch rows produced equal yields (77 to 78 bu/A averaged across 5 years, six varieties, and two early and late planting dates). A seeding rate of 10 seeds per row foot produced an average of 70.5 bu/A or about a 9 percent reduction in yield. For October versus late-November planting dates, average yields (5 years and 6 varieties were as follows:


Seeding Rate (seeds/row ft.)



Late November














Farm Financial Management Workshops                

A Five Day Short Course Offered by the University of Maryland Cooperative Extension

In This Workshop, You Will Learn To:

> Show Your Farm's Earning - Accurately!

> Plan Your 1999 Cash Flow!

>  Emphasize Profitability - Accurately!

>  Monitor Key Trends in Your Business - Fix Potential Problems Early!

>  Develop a Detailed Business Plan for Your Farm Operation!

> Gain New Confidence in the Financial Management of Your Farm!


Why Do Farmers Need to Improve Their Financial Management Skills?

* Lenders Now Routinely Ask Farmers to Prepare Their Own Financial Statements

* Sound Financial Decisions Can Save You Thousands of Dollars

* FSA Now Requires Farmers to Take Financial Management Training


Sound Financial Planning Provides You:

* Tools to Better Manage Your Farm and Family's Scarce Resources

* Good Communications with Lenders

* Improved Cost Control

* Peace of Mind


Benefits You Will Gain From Attending the Workshop

By the end of the course, you will be able to do the following:

>Develop and Analyze Financial Statements and Budgets

Balance Sheets *   Income Statements *   Cash Flow Budgets *   Household Budgets

> Analyze Financial Trends and Recognize Potential Problems in Your Business

Financial Ratio Analysis *  Trend Analysis

>Prepare a 4-Year Business Plan that Focuses on Your Personal Goals and Financial Situation

Investment Planning *   Production Alternatives *  Diversification *  Credit Needs


The Course Will Be Offered in the Following Locations:

> Georgetown, DE (UofD REC) : December 3, 10, 17, January 14, 21

> Salisbury, MD: December 2, 10, 16, January 21, 28

> La Plata, MD : December 2, 4, 11 January 8, 15

> Hagerstown, MD: December 7, 14, 21, January 4, 11

> Queenstown, MD (Wye REC): December 2, 9, 16 January 13, 20

> Frederick, MD : December 4, 11, 18: January 8, 22

> Westminster, MD: December 9, 16, January 5, 12, 19

Course Registration Deadline: November 16, 1998

Cost: $190.00 per couple. Includes: lunch, workbook and all registration materials for the 5 days.

Sessions Run From: 9:30 a.m. - 3:30 p.m.

For Further Information, please contact Dr. Wes Musser at 301-405-0017 or Fax 301-314-9091

Weather Summary

Week of September 25 to October 1

Readings taken for the previous 24 hours at 8 a.m.
Air Temperature:
Highs Ranged from 93 F on September 27 to 77 F on September 29.
Lows Ranged from 69 F on September 27 to 51 F on 29.
Soil Temperature:
75 F average for the week.
(Soil temperature taken at a 2 inch depth, under sod)

Web Address for the U of D Research & Education Center:



As mentioned on the first page, this is the last weekly issue for the 1998 season. I hope that the information that you received this season has been helpful and relevant. This newsletter would not be possible if we did not have the dedication of many people who put this information together for the newsletter each week. As editor, I would like to express a special thank you to those individuals that contribute.

Please do not hesitate to express your comments and suggestions for improvements for Weekly Crop Update to any member of Delaware Cooperative Extension.

Best Wishes for a prosperous harvest season. See you next month!



Compiled and Edited By:

Tracy Wootten

Extension Associate - Vegetable Crops


Cooperative Extension Education in Agriculture and home Economics, University of Delaware, Delaware State College and the United States Department of Agriculture cooperating, John C. Nye, Dean and Director. Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Is the policy of the Delaware Cooperative Extension System that no person shall be subjected to discrimination on the grounds of race, sex, disability, age or national origin.