Posts Tagged ‘16:3’

Recent Topics on Gordon’s Blog

Friday, June 13th, 2008

For Current Agricultural Information from the UD Kent Co. Extension Office Visit

www.kentagextension.blogspot.com

 

Recent Topics:

Straw Removal Pros and Cons
Watch for Bacterial Soft Rot in Corn
Barley Harvest in Full Gear
Grasshopper Watch
Check Wheat Fields for Scab Before Drydown – DON (vomitoxin) Information
Grain Markets – What is Driving Corn and Soybean Prices
Poultry – Fly Control
Farm Safety -Heat Related Illnesses
Early Growth Stage Designations in Soybeans
Corn – Uneven Stand Effects
Pictures of Current Crop Problems
Continue Scouting for Armyworms
Good Pricing Opportunities for Corn and Soybeans
More on Head Scab in Wheat

Potato Disease Advisory #8 – June 12, 2008

Friday, June 13th, 2008

Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu

Disease Severity Value (DSV) Accumulation as of June 11, 2008 is as follows:
Location: Broad Acres, Zimmerman Farm, Rt. 9, Kent County
Greenrow: April 27

  LATE  BLIGHT EARLY BLIGHT
Date Daily DSV Total DSV Spray Recs Accumulated P days*
5/16 – 5/17 6 27 7-day interval 141
5/18 – 5/21 5 32 5-day interval 166
5/22 – 5/26 0 32 7-day interval 203
5/30 – 6/1 3 35 10-day interval 252
6/2 – 6/4 1 36 10-day interval 279
6/4 – 6/5 4 40 5-days 279
6/5 – 6/6 2 42 5-days 288
6/6 – 6/7 1 43 5-day 298
6/7 – 6/11 0 43 10-day interval 321

* P days- We use the predictive model WISDOM to determine the first fungicide application for prevention of early blight as well.  The model predicts the first seasonal rise in the number of spores of the early blight fungus based on the accumulation of 300 physiological days (a type of degree-day unit, referred to as P-days) from green row.  To date, 307 P-days have accumulated at the site.  The 300 P-day threshold has been exceeded so fungicides for early blight should now be applied if not already done.

The Spray Recs column in the table is also generated by the WISDOM software program. This recommendation combines the DSV accumulation for late blight as well as the P-day accumulations for early blight and computes a spray recommendation. This is presented as a guide only. Spray decisions should be made with local conditions in mind and this information can help to determine if disease conditions are favorable.

If pink rot or leak is a concern and no pink rot fungicide was applied at planting consider applying one of the following when potatoes are nickel-sized and repeating 14 days later. Apply in as much water as possible (20-30 gal/A): Mefanoxam/chlorothalonil (Ridomil/Bravo or Flouranil) 2 lb/A, or Ridomil Gold/MZ 2.5 lb/A, or Ridomil Gold/Copper 2 lb/A. If Platinum/Ridomil Gold was applied at planting the label allows one foliar application of one of those products at tuber initiation if conditions warrant.

For specific fungicide recommendations, see the 2008 Delaware Commercial Vegetable Production Recommendations Book.

Volume 16, Issue 3 – April 4, 2008

Thursday, April 3rd, 2008

PDF Version of WCU 16:3 – April 4, 2008

In this issue:

Vegetables
Vegetable Transplant Height Control
Watermelon Seedling Diseases in the Greenhouse
Weed Control in Peas

Agronomic Crops
Soybean Rust Update
Early Fungicide Applications of Headline to Wheat
Weed Control in Forages
Weed Control for No-Till Soybeans
Recent Changes to Acetochlor Labels
Pre-Packaged Mixtures for Corn
Soil-Applied Herbicides for Soybeans
Grain Marketing Highlights

Announcements
E-Commerce in Agriculture Study Participants Sought
New Newsletter for New Castle County Growers
Certified Pesticide Applicators Test – April 23
Small and/or Beginning Farm Series Workshop: Using Small Scale Tillage Equipment and Mowers
Recent Topics on Gordon’s Blog

Weather

Soil-Applied Herbicides for Soybeans

Thursday, April 3rd, 2008

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

Over the past year, a number of herbicide combinations have been registered for soil-application with soybeans. These products are prepackaged or co-packs of existing herbicides. Most of these products control a wide-spectrum of broadleaf weed species, but they are not very effective for grass control. The rate of these products depends on the need. Higher rates will provide a longer period of weed control. All of these products have recommended rates for use with Roundup Ready soybean (given below); but higher rates should be used if applications are made more than 2 weeks prior to planting. Higher rates should also be used if non-Roundup Ready soybeans are planted. 

Product name Rate (oz/A)

Contains

Rate

Also contains

Rate
Synchrony XP 1.5 oz/A

Classic

1.3 oz/A

Harmony GT

0.14 oz/A
Canopy 3.0 oz/A

Classic

1.3 oz/A

Sencor

2.57 oz/A
Canopy EX 2.0 oz/A

Classic

1.8 oz/A

Express

0.18 oz/A
Valor XLT 3.0 oz/A

Classic

1.2 oz/A

Valor

1.8 oz/A
Gangster 3.0 oz/A

FirstRate

0.5 oz/A

Valor

2.5 oz/A
Authority First or Sonic 3.2 oz/A

FirstRate

0.3 oz/A

Authority

2.7 oz/A
Authority MTZ 14 oz/A

Authority

3.4 oz/A

Sencor

5 oz/A
Boundary 1.25 pt/A

Dual Mag

0.82 pt/A

Sencor

4.2 oz/A
Prefix 2 pt/A

Dual Mag

1.1 pt/A

Reflex

0.95 pt/A

Pre-Packaged Mixtures for Corn

Thursday, April 3rd, 2008

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

There have been changes in formulation and ratios of products for many pre-packaged herbicides over the past few years. As a result, check the label for your product of choice since often the new formulations recommend lower use rates than what was previously labeled. Below is a chart on rates of the most common pre-packaged mixtures used in the area, general use rate, and the amount of products they are providing:

 Herbicide Rates Atrazine Chloroacetamide
(grass herbicide)
Bicep II Magnum or Cinch ATZ 1.6 qts 1.24 qt 1.0 pt Dual II Magnum
Fultime 3.0 qts 1.2 qt 2.25 qt Topnotch
Guardsman Max 1.5 qts 1.3 qt 13.5 oz Outlook
Keystone 2.6 qts 1.5 qt1 2.4 qt Topnotch2
Harness Xtra 5.6L 1.7 qts 1.1 qt 0.76 qt Harness
Lumax 2.5 qts 0.625 qt 1.76 pt Dual II Magnum
AND 5.4 oz Callisto3
Lexar 3.0 qts 1.3 qt 1.3 pt Dual II Magnum
AND 5.4 oz Callisto3
SureStart 3 pt/A none 0.88 pt Surpass
2 fl oz Stinger
0.45 oz wt Python

1The atrazine formulation in Keystone is not available in other products.
2Not a true comparison since Topnotch is a capsule suspension formulation and the acetachlor in Keystone is a suspo-emulsion formulation.
3Callisto is not a chloroacetamide.

Weed Control in No-Till Soybeans

Thursday, April 3rd, 2008

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

Time to consider your options for no-till soybean burndown programs, and it is particularly important if you have glyphosate-resistant horseweed (or marestail). Weed control for no-till soybeans has become more complicated as glyphosate-resistant horseweed has spread and species-shifts have occurred because of over reliance on glyphosate for soybean weed control. A new fact sheet “Approaches to Pre-Plant Weed Control in No-till Soybeans” is available at www.rec.udel.edu/weedscience/Fact%20Sheets_web/NT_soybeans_08_WF19.pdf. This fact sheet discusses the need for a combination of non-selective herbicide plus a plant growth regulator (2,4-D or dicamba) plus a residual herbicide for consistent weed control. In addition, the disadvantages of waiting until late spring to spray no-till herbicides are discussed.

Weed Control in Forages

Thursday, April 3rd, 2008

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

If you have not done so yet, be sure to examine your hay, pasture, and alfalfa fields for weed infestations. Earlier applications are much more effective than later, as weeds get larger and start to produce seeds. For grass hayfields or pastures, weed control options include dicamba (Banvel or Clarity), 2,4-D, Overdrive, Crossbow, or Cimarron. Cimarron and Crossbow provide residual control, while the other products do not.

For pure alfalfa fields, Buctril, 2,4-DB, Pursuit or Raptor are labeled. Pursuit and Raptor will provide both postemergence control as well as residual control. For mixed stand of legumes and grasses, Pursuit is an option.

Be sure to read the label and follow all precautions concerning grazing and haying restrictions as well as overseeding and re-seeding restrictions.

Weed Control in Peas

Thursday, April 3rd, 2008

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

Weed control options remain limited for processing peas. Pursuit, at 1.5 to 2.0 fluid ounces per acre, needs to be used as a pre-plant incorporated or preemergence treatment and is used primarily for broadleaf weeds. Preemergence applications of Command at 8 to 16 fl oz or Dual at 0.5 to 1 pt/A are labeled for control of annual grasses and some broadleaf weeds. Basagran is the only recommended herbicide for postemergence control of broadleaf weeds. Apply Basagran at 1.5 to 2 pints per acre after peas have more than three pairs of leaves. Do not add oil concentrate. Select, Assure II, Targa, or Poast can be used for postemergence grass control.

Recent Changes to Acetochlor Labels

Thursday, April 3rd, 2008

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

 Acetochlor is a preemergence herbicide for corn that controls annual grasses and some broadleaf weeds. It is in the following products: Harness, Harness Extra, Degree, Degree Extra, Topnotch, Fultime, Keystone, Surpass, TopNotch, and SureStart. These products have had the rotational restrictions modified, allowing more crops to be planted the following spring (previously only soybeans and sorghum). The label now allows for rotation to: alfalfa, clover, barley, potatoes, oats, tobacco, others.

However, the groundwater restrictions have not changed. The restrictions pertain to groundwater quality. The restrictions are based on depth of groundwater within one month of planting and the combination of soil type and organic matter. Do not apply acetochlor if the groundwater depth is within 30 feet and you have sands with less than 3% organic matter, loamy sands with less than 2% organic matter, or sandy loam with less than 1% organic matter.

Georgetown Weather Summary

Thursday, April 3rd, 2008

Weather Summary

Carvel Research and Education Center Georgetown, DE

Week of March 27 to April 2, 2008

Readings Taken from Midnight to Midnight

 

Rainfall:

0.06 inch: April 1
 

Air Temperature:

Highs Ranged from 78°F on March 28 to 46°F on March 30.
Lows Ranged from 58°F on April 1 to 30°F on March 30.
 

Soil Temperature:

52°F average.
(Soil temperature taken at a 2″ depth, under sod)

Additional Delaware weather data is available at http://www.rec.udel.edu/TopLevel/Weather.htm