Volume 8, Issue 25                                                                                             September 8, 2000

 

Vegetables

 

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

 

Peppers.

Since corn earworm catches remain above 20 per night in many areas, sprays are needed on a 5-day schedule for corn borer, corn earworm, fall armyworm and aphid control. Trap catches can be found at http://www.udel.edu/IPM/latestblt.html

 

 

 

Lima Beans.

Corn earworm egg laying, larval counts and pod damage continues to increase. When possible, fields should be scouted twice a week to effectively time insecticide applications. Controls are needed if you find one larva per 6 foot of row. In many cases, multiple applications (2-4 sprays) will be needed to control newly hatched larvae.

 

Snap Beans.

Corn borer and corn earworm moths continue to be found laying eggs in snap bean fields. Be sure to watch for corn borer larvae boring into the petioles and stems on small plants. If you notice an abundance of corn borer moths laying eggs in fields before the bud stage, be sure to check plants for flagged leaves and infested petioles. If petioles are infested, a spray will be needed before the bud spray to prevent larvae from moving out of stems and tunneling into small pods. Processing snap beans should be sprayed at the bud stage for corn borer control and at the pin stage for corn earworm and corn borer control. After the pin spray, sprays are needed on a 4-day schedule until harvest.

 

Spinach.

Continue to watch for webworms and beet armyworm in spinach fields throughout the state. The first webworms have been detected on small plants.

 

Sweet Corn.

All fresh market silking sweet corn should be sprayed on a 2-3day schedule for corn earworm, corn borer and fall armyworm control.

 

Vegetable Diseases -  Kate Everts, Extension Vegetable Pathologist, University of Delaware and University of Maryland;  everts@udel.edu

 

Melcast for Watermelons

EFI Values (Environmental Favorability Index)

Do not use MELCAST if there is a disease outbreak in your field, it is a preventative program.  Any questions please

call Phil Shields at (410) 742-8788 or e-mail: ps136@umail.umd.edu

 

Location

8/26

8/27

8/28

8/29

8/30

8/31

9/1

Bridgeville, DE

1

3

4

2

1

1

1

Laurel, DE

(Collins Farms)

1

4

6

4

2

2

5

Galestown, MD

1

3

7

2

7

1

4

Georgetown, DE

1

2

5

4

5

1

2

Hebron, MD

2

3

7

6

4

2

6

Salisbury, MD

2

3

5

5

4

2

2

Vienna, MD

1

3

5

3

2

1

0

Laurel, DE

(Vincent Farms)

2

4

6

5

5

2

2

The first fungicide spray should be applied when the watermelon vines meet within the row.  Additional sprays

  should be applied using MELCAST.  Accumulate EFI (environmental favorability index) values beginning the

  day after your first fungicide spray.  Apply a fungicide spray when 30 EFI values have accumulated by the

  weather station nearest your fields.  Add 2 points for every overhead irrigation.  After a fungicide spray, reset

  your counter to 0 and start over.  If a spray  has not been applied in 14 days, apply a fungicide and reset the

  counter to 0 and start over.  The first and last day listed above can be partial days so use the larger EFI value

  of this report and other reports for any specific day.

 

  If, for some reason, a serious disease outbreak occurs in your field, return to a weekly spray schedule.

More detailed information concerning MELCAST and sample data sheets are available on the web at http://www.agnr.umd.edu/users/vegdisease/vegdisease.htm or http://www.udel.edu/IPM/      v

 

Field Crops

 

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

 

Soybeans.

Corn earworm moth catches have decreased due to the cooler weather; however, egg laying can still be observed. All fields should be watched through the end of the month for economic levels. In the past, diseases have helped to crash populations at this time of year. It has been our experience that you need to see at least a week of cool, rainy weather combined with warm, humid days to get fungal pathogens to develop and spread between larvae. You should also look for parasitized worms and pod feeding before making a treatment decision. The treatment threshold is 3 per 25 sweeps (narrow rows), 5 per 25 sweeps (wide rows) or one per foot of row.

 

 

 

Fall Cover Crop Seeding - Richard W. Taylor, Extension Agronomist; rtaylor@udel.edu

 

As harvest season begins, it’s time to consider whether cover crops fit your cropping system and what cover crop to use.  Actually with timely management, cover crops fit most cropping systems except when crop conditions or crop maturity dictate a late harvest (November or December).  Although cover crops fit in most situations, the decision to use cover crops is made by balancing the benefits versus the costs.  Always take the time to weigh all potential benefits and all expected costs before deciding if cover crops are right for you.

 

From the point of view of nutrient management, unfertilized, grass cover crops are an ideal choice.  Not only do grass cover crops tie up available leftover nitrogen and other nutrients but they also provide protection to the soil by limiting soil erosion losses from water and wind.  Cover crops can build soil fertility (at the same time reducing nutrient losses off field), soil tilth, soil organic matter, improve soil health, and suppress weed competition.

 

To obtain the maximum benefits, seed grass cover crops as early as feasible following grain or crop harvest.  One of the best choices as a cover crop is cereal rye since it grows at lower temperatures than wheat, barley, or oats.  The other cereals just mentioned also can be used but must be planted earlier than rye to obtain adequate cover for soil protection.  If planting a cover crop before the fly-free date for Hessian fly, consider winter oats since oats are not a host crop for Hessian fly.

 

Rye should be seeded at two to three bu/A.  It can be seeded by drilling it into either crop stubble or a prepared seedbed or broadcasting it over a field and lightly disking or running a field cultivator over the field to incorporate the seed.  For wheat, barley, and oats, increase the seeding rate used for sowing the crops for grain by about fifty percent.  This should increase the amount of soil coverage you will get in the fall before cold weather halts active growth.  Always plant cover crops as soon as a field is harvested to allow the maximum fall growth possible.

 

Finally, next spring stay on top of the rainfall pattern.  Dry springs and growing cover crops can quickly deplete soil moisture.  If subsoil moisture loss is a likely event, you should plan to use a burndown herbicide to kill the cover crop before soil moisture loss reaches a critical stage.  The residue left on the field still will provide you with improved rainfall infiltration, weed suppression, and other benefits.

 

 

Lime Applications - Richard W. Taylor, Extension Agronomist; rtaylor@udel.edu

 

If you’ve been soil testing on a regular cycle, you know which fields need lime next year.  The fall is an excellent time to consider applying the needed limestone to your fields.

 

Although all bets are off this year, generally fall rainfall patterns mean the soil will be dry enough to support the weight of lime application equipment sometime in the next few months.  Lime should be applied when soils are dry enough so compaction does not pose a problem.  By fall applying lime, you allow time for limestone to react with the soil acidity plus move downward with winter rains and with the early spring freezing and thawing action.  Also, the freezing and thawing action will loosen the soil and move soil bulk density (a measure of soil tightness) back to a healthy level.

 

Never lime just because it’s been a few years since you applied some.  Use your soil test results to accurately determine the proper amount to apply.  Not only do different crops have different lime requirements but, each soil requires a different amount to adjust acidity back to the ideal range.  Also, pay attention to the soil calcium and magnesium levels and adjust your choice of limestone (dolomitic if you need more magnesium or calcitic if you have too much magnesium or not enough calcium) so these nutrients are maintained at appropriate levels.  If the pH is in the correct range for your crops and soil type but the calcium level is low, gypsum or calcium sulfate can be applied to raise calcium levels while not affecting the soil pH level.

 

 

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

 

Count Down To Harvest

As we enter the second week of September, one thing is for certain and that is that the 2000 U.S. corn and soybean harvest has begun. General consensus has it, among commodity analysts, that 2000 crop production will be record size and near record. The next USDA crop report will be released on Tuesday, September 12th at 7:30 a.m. CST. Corn and soybean prices declined sharply on the release for the September 6th Spark's Crop Report that estimated U.S. corn production at 10.313 billion bushels and soybean production at 2.926 billion bushels. Although these estimates were slightly lower than USDA's August numbers, the estimates were reported to be larger than what grain traders generally expected.With the fall harvest comes the necessity to decide what one should do with unpriced corn and soybeans? To a large extent what one does depends upon individual options that are available, e.g., whether storage or enough storage is on hand, what basis level is being bid for corn or soybeans on a given day during the harvest period, how much price and/or basis gain can be expected, etc. 

Market Situation

Technical analysts are beginning to suggest that the bear market has run its course and that we can now look for price levels to improve over time for corn and soybeans. However, a word of caution is in order plan on and expect harvest price pressure that will cause a downward price move for both corn and soybeans until we work through harvest. Harvest is just beginning in the Midwest and is very likely to be completed by early November, weather permitting. How much harvest pressure can we expect? Harvest price pressure is estimated to be 20 to 30 cents per bushel for corn and 30 to 50 cents per bushel for soybeans. The extent of the price pressure depends largely on the call USDA makes regarding crop size in the September report.

Current basis levels locally are at historically low levels at 5 to 10 under for Dec corn and 20 to 35 under Nov for soybeans. We are normally 10 to 20 over this time of year for Dec corn and even (0) for Nov beans. 

Harvest Marketing Strategy for Unpriced Grain and Soybeans