Volume 12, Issue 10                                                                     May 28, 2004

 

Vegetables

Pea Harvest Progress Ed Kee, Extension Vegetable Crops Specialist; kee@udel.edu

 

Pea Harvest began 10-14 days ago and yields in most cases have been good, ranging in the 3-4,500 pound per acre range.  A few fields experienced heavy, packing rains soon after planting and the resulting compaction and uneven stand took their toll on yields.

 

In some cases, warm weather coupled with dry soil conditions accelerated maturity, causing some acreage to be by-passed.  However, this year’s pea yields and harvest progress are very good.

 

 

 

Pickling Cucumber Plantings Ed Kee, Extension Vegetable Crops Specialist; kee@udel.edu

 

Pickle planting is in full-swing, with many growers having 6-7 plantings in the ground.  Emergence and weed control looks good to date.  We will be planting our variety trials in June at Fifer Orchards near Camden-Wyoming, and in July at Richard Carlisle’s Pine Breeze Farms, in Sussex County.

 

In the May 7 issue of Weekly Crop Update, the use of Sandea as a post-emergence weed control material was discussed.  Briefly, it is labeled at 0.5-0.66 ounces per acre and will control red-root pigweed, nutsedge, along with other problem weeds.

 

 

 

Lima Bean Fertilizer Programs Ed Kee, Extension Vegetable Crops Specialist; kee@udel.edu

 

Lima bean planting has just begun.  Our recommendation for single-crop lima beans calls for 60-80 pounds of Nitrogen per acre.  This can be applied broadcast, or split into applications broadcast, at-planting, and sidedressed; or some combination of the three.  Research data and commercial experience has not consistently demonstrated a clear advantage of one timing or another.

 

The recommendation for nitrogen for lima beans planted after peas is 0-20 pounds of nitrogen per acre.  Of course, there is significant residual nitrogen from the peas that allows this reduction.

 

Phosphorus and Potassium should be applied according to soil test recommendations.  However, if the soil is testing high or excessive, no phosphorus is required, especially after peas, and potassium at 50-75 pounds per acre is appropriate. 

 

 

 

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

 

Cucumbers.
All fields should be scouted for cucumber beetles and aphids. Fresh market cucumbers are susceptible to bacterial wilt, so treatments should be applied before beetles feed extensively on cotyledons and first true leaves. Pickling cucumbers have more tolerance to wilt, but a treatment may be needed if you find 2 or more beetles per plant and significant damage can be found on the cotyledons. A treatment should be applied for aphids if 10 to 20 percent of the plants are infested with aphids with 5 or more aphids per leaf.  Actara, Fulfill, Thiodan or Lannate will provide aphid control. Be sure to watch for bees foraging in the area and avoid insecticide applications on blooming crops.

Melons.
Continue to scout all melons for aphids, cucumber beetles, and spider mites. The threshold for mites is 20-30% infested crowns with 1-2 mites per leaf. Acramite , Capture, Danitol, Agri-Mek or Kelthane will provide control, but should be rotated to avoid the development of resistance. The treatment threshold for aphids is 20% infested plants with at least 5 aphids per leaf. Actara, Fulfill, Lannate and Thiodan are labeled on melons and will provide melon aphid control.  Continue to watch fields carefully for cucumber beetles. Be sure to look under the plastic where beetles can often hide until disturbed. We have found a number of fields with high levels and beetles can be found in most fields.

 

Peppers.
Fields should be  sampled  for thrips and corn borers.  Although corn is growing rapidly and should be more attractive to corn borer moths, you should still watch for corn borer egg masses in isolated fields ( i.e. not near corn fields). You should also check local moth catches in your area http://www.udel.edu/IPM/traps/latestblt.html.  A treatment with a pyrethroid may be needed if corn borer moth catches exceed 10 moths per night, especially if there is no corn in the area or you are using rye strips as windbreaks.  In general, 2 applications will be needed to achieve effective control.  Thrips can cause damage in peppers by vectoring tomato spotted wilt virus and by causing direct plant damage. Although there are no available thresholds, a treatment may be needed if you see populations increasing. Baythroid, Capture, Spintor and Warrior will provide thrips control.


Potatoes.
Colorado potato beetle (CPB) adults, egg masses and the small to medium size larvae can be found in fields where an at-planting CPB material was not used.  A treatment should not be needed for adults until you find 25 beetles per 50 plants and defoliation has reached the 10% level. Once larvae are detected, the threshold is 4 small larvae per plant or 1.5 large larvae per plant.  Avaunt + PBO, Actara, cryolite, Spintor or Provado will provide control. Corn borer catches have increased in some areas and sprays will now be needed 3-5 days after an increase in trap catches. Be sure to check our website (http://www.udel.edu/IPM/traps/latestblt.html) for the most recent moth catches in your area. Avaunt, Ambush, Baythroid, Furadan, Penncap, Pounce or Spintor will provide control. If you are scouting for infested terminals, the first treatment should be applied when 20-25% of the terminals are infested. Furadan or Monitor will provide the best control if you are waiting until you see infested terminals.  We are also finding economic levels of potato leafhopper adults in the earliest planted fields. As a general guideline, controls should be applied if you find ½ to one adult per sweep and/or one nymph per every 10 leaves. Dimethoate, a  pyrethroid, Actara or Provado will provide control.

Snap Beans.
All fields should be scouted for leafhopper and thrips activity, especially seedling stage beans. The thrips threshold is 5-6 per leaflet and the leafhopper threshold is 5 per sweep. If both insects are present, the threshold for each should be reduced by 1/3. Dimethoate, Lannate, Asana, Capture, or Warrior will provide control of both insect pests.

Sweet Corn.
Flea beetles and cutworms are still active in seedling stage sweet corn. The treatment threshold for flea beetles is 5% infested plants. The cutworm threshold is 3% cut plants or 10% leaf feeding. Continue to sample any corn in the whorl stage to pretassel stage for European corn borer larvae.  A treatment should be applied if 15% of the plants are infested. In recent years, Avaunt (whorl stage only), Baythroid, Mustang, Penncap, Spintor or Warrior has provided effective control. If economic levels of corn borers are present in pretassel to tassel stage corn, two sprays spaced 3-4 days apart are often needed. In addition, we have started to find the first corn earworm moths. The first silk sprays will be needed as soon as ear shanks are visible. Treatment will be needed on a 5-day schedule in Kent and Sussex Counties. 

 



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


Fusarium Wilt.

Fusarium wilt in watermelon has been detected in several fields on Delmarva this spring.  Symptoms in new transplants are stunted growth, necrotic leaves, wilting, and a distinct vascular discoloration.  Infected fields may appear to recover; however symptoms often reappear later in the season when the vines produce runners.  Wilting then becomes more severe as fruit increase in size and plants appear water-stressed even under conditions when soil moisture is adequate.  Wilt occurs on crown leaves first, then on runners and eventually on the whole plant.  Infected stems may have a red, brown or black gummy exudate and the vascular system of the plant is discolored.

 

Management of Fusarium wilt has been accomplished in the past through long rotation (5 to 6 years), planting resistant cultivars, and fumigation.  However, fumigation may fail to control the disease because Fusarium can quickly reinvade fumigated ground.  A new aggressive form of the pathogen (Fusarium oxysporum f. sp niveum, race 2) has been detected in Maryland and Delaware.  The development of this new race and an increase in acreage of seedless watermelon has led to an increase in Fusarium wilt (few seedless cultivars have resistance to this disease).  Dr. Xin-Gen Zhou tested several seedless watermelon cultivars to identify tolerance or resistance to Fusarium wilt.  The field was very highly infested with race 2 of the pathogen, however you can see how the cultivars compare to each other.

 

 

 

Wilt

(%)

Marketable fruit yield

Cultivar

Source

No./A

t /A

Millionaire

Seedway........................................

97 a *

293 ab

1.6 ab

Triple Star

Seedway........................................

93 a

440 ab

2.0 ab

Genesis

Seedway........................................

93 a

0 a

0.0 a

Seedway 4502

Seedway........................................

87 a

733 ab

4.3 ab

Sugarheart

Siegers...........................................

80 a

880 b

4.7 b

Millennium

Seedway........................................

53 b

293 ab

1.5 ab

Seedless Sangria

Siegers...........................................

7 c

1467 c

9.7 c

*Mean values in each column followed by the same letter are not significantly different at P = 0.05 according to Fisher’s protected least significant difference test.

 

MELCAST for Watermelons.

The weather-based forecasting program MELCAST has begun for 2004.  MELCAST was developed at Purdue University.  It uses weather data to schedule protectant fungicide applications for anthracnose and gummy stem blight of watermelon, so that instead of spraying on a 7-day schedule, fungicides are applied according to the weather.  We will publish EFI information in the Weekly Crop Update and on the University of Delaware IPM web page (http://www.udel.edu/IPM/).  It will also be available by fax, three times weekly.  If you would like to receive the EFI information by fax, please call UD REC at 856-7303 and give your name, address, phone and fax number to Lisa Dorey at (302) 856-7303.  In Maryland, call UM LESREC at (410) 742-8788 and give this information to the secretary.  If you signed up to receive a report, it should have started this week.  If you have not received any reports please call Lisa Dorey at (302) 856-7303 and give us your name and fax number or e-mail address.  In addition, this information is available on the web at http://www.agnr.umd.edu/users/vegdisease/vegdisease.htm. 

 

To use MELCAST for watermelons, apply the first fungicide spray 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 at the weather location nearest your field.  Add 2 points for each overhead irrigation that is applied to the field.  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, reset the counter to 0 and start over.

 

MELCAST for Cantaloupes and TOMCAST for Tomatoes.

In addition to MELCAST for Watermelon, we have two models that are designed to help you make decisions on when to spray for diseases.  MELCAST for Cantaloupes is a fungicide application program for Alternaria leaf blight.  It can be used by anyone growing a powdery mildew resistant variety such as Athena.  To use MELCAST for Cantaloupe, apply the first fungicide spray when the cantaloupe 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.  Add 2 points for each overhead irrigation that is applied to the field.  Apply a fungicide spray when 20 EFI values have accumulated at the weather location nearest your field.  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.

 

TOMCAST is a spray forecaster for leaf blights and fruit diseases of processing tomato.  However, it does not work for bacterial diseases. In fields that are not rotated away from tomatoes and in late-planted fields, begin sprays shortly after transplanting.  In all other areas begin sprays when crown fruit are one-third their final size.   Additional sprays can be scheduled using TOMCAST.  Sprays should be applied after accumulating 18 DSV’s (disease severity values) since the last fungicide application.  Scout fields for late blight.  If late blight occurs additional sprays are warranted (see Delaware Extension Bulletin 137).  Note:  We provide TOMCAST data at the request of interested growers. However, we have not tested the model in our area and don’t have the resources to adequately support it.  Please use it on small acreage to become comfortable with it.

 

The three disease models are available at http://www.agnr.umd.edu/users/vegdisease/vegdisease.htm.  In addition you can receive the models by e-mail or fax.  To sign up, please call Lisa Dorey at (302) 856-7303.

 

 

  

Vegetable Crops Diseases - Bob Mulrooney, Extension Plant Pathologist, bobmul@udel.edu

 

Potatoes.

Late Blight Advisory.

We are using the E-WEATHER SERVICE from SkyBit, Inc. as we have in the past.  The service determines specific requested weather parameters (temperature, relative humidity and rainfall) at Joe Jackewicz’s farm based on calculations of data from the nearest National Weather Service stations.  This weather data is used in the WISDOM software program for predicting late blight and making spray recommendations.

 

Disease Severity Value (DSV) Accumulation as of May 26, 2004 is as follows:

Location: Joe Jackewicz Farm, Magnolia, DE. Greenrow: April 25, 2004

 

Remember that 18 DSV’s is the threshold to begin a spray program

 

 

Date

 

Daily DSV

 

Total DSV

Spray Recommendation

4/25- 5/2

4

4

none

5/3

8

12

none

5/9

2

14

none

5/13

1

15

none

5/17

2

17

none

5/18

1

18

none

5/19

4

22

7-day

5/20

2

24

7-day

5/21

2

26

7-day

5/25

2

28

5-day

 

Remember that these values are for potatoes that would have about 50% emergence and made a row that you can see on or before April 25th . Any fields that emerged after May 3 have accumulated 16 DSV’s so far and will probably reach 18 DSV’s soon.

 

Growers who do not want to rely only on the DSV calculations for scheduling fungicide applications should apply mancozeb (Dithane, Pencozeb, Manex II) or Bravo before plants canopy down the row and repeat on a 7-day schedule. Late blight has not been a problem here in Delaware for many years and unless you have seed from an unknown source, the risk of late blight is very low.

 

 

 

Field Crops

 

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

 

Alfalfa.
Be sure to check all fields for leafhoppers within one week of cutting.  You should also sample all spring planted fields since they are extremely

susceptible to damage. Once the damage is found, yield loss has already occurred. We are starting to find the first nymphs which often cause damage very quickly. The treatment thresholds are 20 per 100 sweeps on alfalfa 3 inches or less in height, 50 per 100 sweeps in 4-6 inch tall alfalfa and 100 per 100 sweeps in 7-11 inch tall alfalfa. Baythroid, dimethoate, Mustang or Warrior will provide effective control.

 

Field Corn.
Continue to scout corn up to V-5 stage for cutworms. With the dry weather, we continue to find cut plants and larvae feeding below the ground level.  Under these conditions, a rescue treatment will be most effective if applications are made late in the day, you use 30 gallons of water per acre and materials are directed to the base of plants.  A pyrethroid or Lorsban will provide control. If large worms are present, you will need to use the higher labeled rates.

 

Continue to scout for true armyworms feeding in the whorls of no-till corn. Be sure to carefully sample no-till fields where a grass cover or volunteer small grains were burned down at planting. The treatment threshold for armyworms in corn is 25% infested plants with larvae less than one-inch long.  We are also seeing cereal leaf beetle adults feeding in whorl stage plants.  No controls will be needed until you find 10 beetles per plant and 50% of the plants exhibit damage. The first small European corn borer larvae can be found in the earliest planted non-Bt fields. The treatment thresholds are 50% infested plants for irrigated corn and 80% infested for dry-land corn. Since corn is growing quickly, the best time for control will be just at tassel emergence as long as larvae have not bored into the midribs of leaves.

 

Small Grains.
Continue to scout all fields for grass sawfly and armyworms. Although sawfly populations have been generally low, we have started to find head clipping by sawfly larvae. Once you find twice the number of clipped heads compared to sawfly larvae, the damage is generally already done. We continue to see an increase in armyworm activity in both wheat and barley. Remember, armyworms will clip heads quicker in barley so the threshold is lower than for wheat. 

 

In both wheat and barley, the treatment threshold for sawflies is 2 per 5 foot of row innerspace or 0.4 per foot of row. The armyworm threshold is one per foot of row in barley and two per foot of row in wheat. If multiple pests are present in barley, your only control option is Lannate.  In wheat, your options include Lannate, Mustang, or Warrior.

 

Soybeans.
Grasshopper and bean leaf beetle feeding can be found in seedling stage soybean fields. A treatment for bean leaf beetle will be needed from plant emergence to the second trifoliate when you find 2 beetles per ft. row and a 25% stand reduction. A pyrethroid, dimethoate or Lorsban will provide control. The treatment threshold for grasshoppers is 1 per sweep and 30% defoliation. Asana, Furadan, Lorsban, or Warrior will provide grasshopper control.

 

 

 

Field Crops Diseases - Bob Mulrooney, Extension Plant Pathologist, bobmul@udel.edu

 

Wheat.

The crop continues to look very good. However, a small amount of head blight or scab is beginning to appear in areas that had rain during flowering. The crop is still remarkably free of foliar diseases this season. As mentioned last week, some powdery mildew is appearing on susceptible varieties that were not sprayed.

 

Corn.

There have been a few isolated emergence problems that could be due to soilborne fungal problems. Post emergence damping-off of field corn by Pythium was reported by another lab. I have seen some problems in sweet corn emergence that appears to be caused by Fusarium. Nothing can be done at this point unfortunately except replant if the stand loss is serious enough to warrant replanting.

 

 

 

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

 

The Chaos Theory Impacting Soybeans.

The chaos theory is a critical point influenced by instability, as is being seen in the soybean charts at this juncture. Bullish supply and demand factors doubled the price of soybean futures from the July 2003 contract close ($5.32) to the high price posted in April 2004 ($10.64). In early May, rumors surfaced concerning China's desire to cancel some purchased shipments. The reports were confirmed as further economic problems were reported involving China. Since then, nearby and new crop soybean futures have dropped nearly $1.00 per bushel, respectively. The recent turn in the soybean market is a reminder of the type of move seen in June 1988.

 

That year, an unexpected rain system developed in the Midwest, effectively ending the drought conditions that existed. (Newsom - DTN Grains Analyst) Having considered that, we still have a long way to go in the current growing season.

 

On another front, heavy rains in the Midwest over the past two weeks are raising new questions about planted acreage for corn and soybeans. USDA previously projected 79 million acres of corn and 75.4 million acres of soybeans would be planted in the U.S. this spring. Too much rain has led to some speculation that some intended corn acreage may have been lost. Our next look at this question will be given in the June 30th Acreage and Stocks report.

 

The first vessel of South American soybean meal has arrived in Wilmington, North Carolina. The significance of this may be that, depending upon weather developments in the Corn belt, we shouldn't expect to see new crop soybean futures retracing the absolute old highs made in both old crop and new crop futures. The arrival of the vessel may also signify that future basis offerings, on the Eastern Shore, for both old and new crop soybean cash markets may not be as strong as offerings made just a short while back.

 

Market Strategy.

New crop soybeans have dropped 23 cents per bushel in the time that it has taken to write this statement. Major liquidation has taken place in the soybean pits and that appears to be continuing to occur. Nevertheless, liquidation is likely to soon be completed and traders will begin to assess the anticipated impact of planting delays for the '04 U.S. corn and soybean crops. On June 11th we will also get another look at the soybean production estimate from the Southern Hemisphere. At this point, it doesn't appear that we should expect much, if any, of a further reduction in the '04 Brazil and Argentina soybean production estimates. Stay tuned, we will soon be attempting to decide whether we look for the return of $3.20 to $3.40 new crop corn futures and $7.75 to $8.00 new crop soybean futures. Astute market observers will recognize that the trend line for soybean futures has turned down. For the moment, the same is not true for the corn and wheat markets.

 

 

 

No-Till Soybean Fields Not Treated Yet - Mark VanGessel, Extension Weed Specialist;  mjv@udel.edu

 

Horseweed control was the most common question I had this year.  There are a number of fields with horseweed well over 12 inches tall and have not been treated yet.  No-till soybean fields that have not been treated yet pose a difficult situation.  2,4-D at 1 pt/A will have very little effect on the tall horseweed plants, however it can be very helpful for primrose control.  ALS-inhibiting herbicides such as Amplify or FirstRate are not particularly good on these tall plants.  Canopy or Canopy XL will be the best options because the high rates of Classic (a component in each of these herbicides).  However, this is not a sound choice to use every year since chlorimuron is an ALS-inhibiting herbicide and we know horseweed has a tendency to develop resistance to ALS-inhibiting herbicides.  If Canopy or Canopy XL do not fit into your herbicide program, two applications of Gramoxone Max will be needed to control/suppress these large weeds.  The final option is resort to tillage to control the existing plants.

 

 

 

Hot Weather and Volatility with Dicamba and 2,4-D - Mark VanGessel, Extension Weed Specialist;  mjv@udel.edu

 

Common sense is critical for spraying dicamba and 2,4-D.  Both of these products are volatile and prone to move from the treated areas as vapors.  Spraying postemergence herbicides in early planted corn or burndowns in no-till fields that have not been treated yet may require additional consideration because of the temperature.  Furthermore, many of the vegetables and fruits have been planted and they are often very sensitive to these herbicides.  It is not recommended to spray dicamba or 2,4-D when the temperature is expected to be 85°F  or hotter; or spray late in the day when temperatures drop below 85°F.  A number of pre-mixes have dicamba (active ingredient in Banvel and Clarity) including, Distinct, Celebrity Plus, Marksman, Yukon, and NorthStar, so the temperature consideration applies to them as well.  Shotgun is a pre-package mixture of 2,4-D and atrazine.

 

 

 

 

Spray Drift Retartdants Not as Effective as They Appear - Mark VanGessel, Extension Weed Specialist;  mjv@udel.edu

 

We conducted a two-year study funded by the Delaware Soybean Board to evaluate the effectiveness of drift retardants (or drift control agents).  We planted soybeans and grain sorghum in adjacent plots and sprayed the soybeans with Roundup Ultra.  We used an air-blast sprayer to generate a 12 to 15 mph wind blowing towards the sorghum and evaluated the sorghum for injury.  From our conclusions, the use of drift retardants cannot be justified for reducing spray drift under windy conditions.  Particle drift, as measured by water sensitive papers and the resulting injury to grain sorghum planted adjacent to the sprayed area, was not lower with the addition of three different spray retardants when applied in 15 mph wind.  Spray retardants did not reduce weed control with Roundup Ultra.  The additional costs to prevent spray drift under these conditions with the three drift retardants could not be justified.

 

 

 

Conventional Soybean Herbicides - Mark VanGessel, Extension Weed Specialist;  mjv@udel.edu

 

I have had a number of questions about herbicides for non-Roundup Ready soybeans.  There is interest in growing conventional varieties for a number of reasons.  Most sound herbicide programs will require a broadleaf plus a grass herbicide at planting.  The Delaware/New Jersey Soybean Weed Management Guide available free at the county offices or online at http://www.rec.udel.edu/weed_sci/WeedPublicat.htm will provide useful information for selecting herbicide programs for the specific weed problems you need to handle.  As always, there is not one program available that will fit all situations.  Be sure to consider all factors, including effectiveness, application timing, and rotational restrictions.  Contact your county agent if you want to review your options.  I believe that with 3 to 4 years of excellent weed control due to Roundup Ready soybeans and good control in rotational crops, the soil seedbank has been drastically reduced and helped make some of the non-Roundup Ready soybean weed programs look excellent.  Timing of herbicide application in non-Roundup Ready soybeans is more critical for effective weed control than with glyphosate.  In addition, it provides a chance to use herbicides with different modes of actions to help prevent herbicide-resistant weeds and weed species shifts.

 

 

 

 

Height Restrictions for Postemergence Corn Herbicides - Mark VanGessel, Extension Weed Specialist;  mjv@udel.edu

 

Now that some of the corn fields are in need of a postemergence sprays,  I am republishing the height restrictions for postemergence herbicides.  These height restrictions are due to potential crop injury. 

 

Broadcast applications refer to an over the top application and directed refers to use of special spray equipment to direct the spray and avoiding the spray coming in contact with the whorl of the corn.   When corn height and collar number are given, base decision on whichever feature is first attained.

 

 

 

 

 

Herbicides

Maximum corn size

Accent

broadcast:  6 collars or 20 in.

directed: 10 collars or 36 in.

Aim

broadcast: up to 8 collars

directed: when necessary

Atrazine

12 inches tall

Banvel

 

Clarity

more than ½ pt/A:

     broadcast: 5 lvs or 8 in.

     directed: 36 inches tall

½ pt/A or less:  36 inches tall

Basagran

No restrictions listed

Beacon

broadcast: min- 4 inches tall

     max- 20 in. tall or 6 collar

directed: pre-tassel

Buctril

pre-tassel

Callisto

30 inches tall or 8 collars

2,4-D Amine

broadcast: 8 inches tall

directed: pre-tassel

2,4-D Ester

broadcast: 8 inches tall

directed: pre-tassel

Evik

directed only: 12 inches tall do not apply 3 weeks before tasseling

Harmony GT

1 - 4 collars or 12 inches tall

Liberty

broadcast: 24 inches tall or 7 collars

directed: 20 to 36 inches tall

Option

broadcast: 16” tall or V5

directed: 16-36” tall

Permit

broadcast: 48 inches tall

directed: when necessary

Resource

broadcast: 2- to 10-lf collars

directed: when necessary; when corn leaves interfere w/ spray

Roundup products

up to 30 inches or 8 collars

Stinger

24 inches tall

Touchdown

up to 8 collars

 

 

 

Premixes

 

Basis

2 collars or 6 inches tall

Basis Gold

5 collars or 12 inches tall

Celebrity Plus

broadcast: 4 to 24 inches tall

Distinct

6 oz rate:  4 to 10 inches  tall

4 oz rate:  up to 24 in.  tall

directed:  4 oz up to 36 inches tall

Equip

broadcast: 12 inches or 4 collars

directed: 12 to 36 inches or 4 to 8 collars

Exceed

broadcast: min- 4 in. tall

     max- 20 in. tall or 6 collar

directed: 20 to 30 inches tall

Field Master

do not apply to emerged corn

Hornet WDG

broadcast: 6 collars

directed: 20 to 36 inches tall

Laddok

12 inches tall

Liberty ATZ

12 inches tall

Lightning

broadcast: 12 inches tall

directed: 20 inches tall

Marksman

broadcast:  5-lf stage or 8 inches tall

Northstar

broadcast: min- 4 inches tall

     max- 20 in. tall or 6 collar

directed: 20 to 30 inches tall

Ready Master ATZ

emergence until 12 inches tall

Shotgun

broadcast: 8 inches tall

directed: 12 inches tall

        or if rate >2 pts

Spirit

broadcast: 20 inches tall or 6 collars (min. 4 in. tall)

directed: 20 to 24 inches tall (before tassel emerg.) 

Steadfast

less than 20 inches or 6 collars

Steadfast

Up to 12 inches or 6 collars

Yukon

spike through 36 inches tall

 

 

 

Correction – Weed Seedling Emergence Web-site - Mark VanGessel, Extension Weed Specialist;  mjv@udel.edu

 

I wrote an article two weeks ago about a model for weed seedling emergence and listed a website where the model could be found.  That website was incorrect.  The website for the predictive maps for weed emergence is at:  http://psu.zedxinc.com/cgi-bin/site.cgi?location=2&user=psu#.  Sorry about any inconvenience.

 

 

 

UPCOMING MEETINGS:

 

Agronomic Crops Twilight Session

 

When:    Wednesday, June 2, 2004

Where: UD Cooperative Extension Research and Demonstration Area (3/4-mile    east of Armstrong Corner, on Marl Pit Rd. – Rd 429, Middletown)          

Time:    6:00 PM

 

Join your fellow producers and the UD Extension team for an interactive and hands-on experience as we discuss demonstration trials and address in-season production issues in small grains, corn, and soybeans. We will focus on:

  • Small grain variety comparisons,
  • Insect, weed, and disease management,
  • A Grain Marketing Update.

 

We will apply for DE Pesticide re-certification credit.

 

This meeting is free and everyone interested in attending is welcome. To register, for more information or special consideration in accessing this meeting, please call our office in advance, at (302) 831-2667.  

 

See you there!  Carl P. Davis, Extension Agent, Agriculture

 

 

                    Weather Summary

http://www.rec.udel.edu/TopLevel/Weather.htm

Week of May 20 to May 26, 2004

Rainfall:

0.65 inches: May 25

0.05 inches: May 26

 

Readings taken for the previous 24 hours at 8 a.m.

 

Air Temperature:

Highs Ranged from 92°F on May 23 to 69°F on May 20.

Lows Ranged from 72°F on May 24 to 61°F on May 20 & 21.

 

Soil Temperature:

78°F average.

(Soil temperature taken at a 2 inch depth, under sod)

 

Web Address for the U of D Research & Education Center: http://www.rec.udel.edu

 

Compiled and Edited By:

Tracy Wootten

Sussex County Extension Agent – Horticulture

University of Delaware

 

 

Cooperative Extension Education in Agriculture and Home Economics, University of Delaware, Delaware State University and the United States Department of Agriculture cooperating.  Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Delaware Cooperative Extension, University of Delaware. It is the policy of the Delaware Cooperative Extension System that no person shall be subjected to discrimination on the grounds of race, color, sex, disability, age or national origin.