Volume 12, Issue 3
April 9, 2004
Volume 12, Issue 3
April 9, 2004
Vegetables
Pea Weed Control –
Post-emergence –
Ed Kee, Extension Vegetable Crops Specialist; kee@udel.edu
Delmarva’s
pea acreage is nearly 40 percent planted, and the earliest planted fields have
emerged and seem to be off to a good start.
Growers, scouts, and field personnel will begin scouting for any
emerging weeds soon. If certain
broadleaf weeds are present, Basagran is the only post-emergence broadleaf
herbicide available for peas. It can be
applied at 1.5 to 2 pints/acre after the peas have more than three pairs of
leaves. Do not add oil concentrate. Smaller weeds are more effectively
controlled. Basagran will control
ragweed, pigweed, smartweed, and velvetleaf.
It will provide fair control or suppression of lambsquarters if applied
when the lambsquarters are small, i.e. one inch or smaller. If taller than two inches, lambsquarters
control will be minimal.
Escaped
grasses can be controlled with Assure II or Poast. Check the label for details.
Vegetable Crop Insects - Joanne Whalen, Extension IPM
Specialist; jwhalen@udel.edu
Peas.
You should begin scouting the earliest planted fields for aphids. As soon as
temperatures warm up, aphids will become active. As the weather fluctuates between warm and
cool temperatures, aphid populations often explode and beneficial insect
activity can lag behind. On small plants, you should sample for aphids by
counting the number of aphids on 10 plants in 10 locations throughout a field.
On larger plants, take 10 sweeps in 10 locations. A treatment is recommended if
you find 5-10 aphids per plant or 50 or more aphids per sweep. Dimethoate or Lannate will
provide aphid control. Be sure to check the labels for application restrictions
during bloom.
New Labels/Changes.
Zeal - This new material from Valent is now
available for mite control in apples, pears and strawberries. It is also
labeled for lygus bug and spittle bug control on strawberries. It is a reduced risk insecticide which acts as an
insect growth regulator against all stages of spider mites and European red
mites. The active ingredient is etoxazole which is a molting inhibitor. It also
has translaminar activity. The use rate is 2-3 oz/acre. The days to harvest
after an application to strawberries is one day.
Lorsban 75WG – This new formulation of
Lorsban will be marketed by Gowan and will replace the old 50W formulation.
Field trials have indicated equal or better control compared to the 4E/50W
formulations.
Danitol 2.4 EC – Please note that the
restricted re-entry interval (REI) is listed incorrectly in the Commercial
Vegetable Recommendations book for all cucurbits ( including cucumbers,
muskmelons, pumpkins, squash and watermelons). The correct REI is 24 hours.
More Label Updates for 2004 for
Vegetable Crops -
The following herbicide labels have been changed or
modified over the past year. This is
intended to make you aware of changes but be sure to read the labels for
complete details.
Snap
beans - Raptor 1AS (BASF) for use postemergence. Label requires a tank-mix with Basagran at 6
to 16 oz/A. Basagran is intended to
safen the Raptor.
Tomato
Dual Magnum 7.62E (Syngenta) for use with plastic
mulch and bare ground
Dual
Magnum 7.62E (Syngenta)
Now has labels (24c registration) for preemergence application for
peppers, cabbage, and spinach. This
registration requires a waiver of liability provided by the DE Vegetables
Growers’ Assocation. Contact
Stinger
3L (Dow AgroSciences) garden beets, brassica, sweet corn, spinach, stone
fruit, turnip root and top. Use rates
range from 2.6 to 8 oz/A depending on the crop.
Be aware of rotational restrictions
Sandea
75DF (Gowan) asparagus,
cucumbers, cantaloupes, pumpkins, winter squash, summer squash, watermelons,
lima beans, green beans, tomatoes, eggplant, and pepper. Has both preemergence and postemergence
activity, but the use pattern varies with the crop and whether it is used with
pasticulture or bare ground. There are
rotational issues with Sandea. Be sure
to read and follow all label restrictions.
Field Crop Insects - Joanne
Whalen, Extension IPM Specialist;
jwhalen@udel.edu
Alfalfa.
Alfalfa weevil population levels
remain light in fields throughout the state. The larvae we are finding at this
time are a result of eggs layed last fall. Overwintered adults can lay eggs in stems any time
temperatures are above 48 degrees F.
The weevil passes through four larval stages in approximately three
weeks. Larvae hatching from spring-laid eggs cause the most damage. As a
general guideline, treatment should be applied if damage is visible on 50
percent or more of the tips. However, a more accurate way to time an
application and try to avoid multiple insecticide applications would be to
sample stems and determine the number of weevils per stem. A minimum of 30
stems should be collected per field, placed top first in a bucket to dislodge
larvae from the tips and then count the number of weevils per stem. The
following thresholds, based on the height of the alfalfa, should be used to
make a treatment decision: up to 11 inches tall - 0.7 per stem; 12 inches
- 1.0 per stem;
13 - 15 inches - 1.5 per stem; 16 inches tall - 2.0 per stem
and 17-18 inches tall - 2.5 per stem.
Field
Corn.
Very
low levels of black cutworm moths continue to be found in traps. These moths
will be attracted to weed covers and larvae will be most active in later
planted corn. Although we can see leaf feeding early, we generally do not see
cut plant damage until we reach 300 DD from peak catches. Also, early cutting
often occurs from variegated cutworm which we can find while sampling for
grubs. Herculex Bt corn can
provide good cutworm control; however, fields should still be scouted for leaf
feeding and cut plant damage. A treatment should be considered in 1-2
leaf stage corn if you find 3 percent cut plants or 10% leaf feeding. Pyrethroids and Lorsban provide
the most cost-effective control. For the most recent pheromone trap catches,
check our website at http://www.udel.edu/IPM/traps/currentbcwtrap.html.
As far as grubs and
wireworms, we have found moderate population levels (just at or below
threshold) in most fields. Since wireworms remain in the soil for 3-5 years as
larvae, we are finding economic levels in the same areas that experienced wireworm damage in past years. Threshold levels of
grubs have been found behind corn, full season and double crop soybean stubble.
We continue to find slugs
in fields that had problems in 2003. Both slug eggs and newly hatched juveniles
can be found under surface trash. In our region, most field slugs pass through
a single generation per year. Although they generally overwinter in the egg
stage, we can often find juveniles and adults all winter, especially if
conditions are warm. Since slugs may live 12 to 15 months and eggs are
laid both in the early spring and fall, overlapping generations of adult and
juvenile stages may be observed. The following factors favor slug outbreaks:
no-tillage field crop production practices; development of dense weed cover or
addition of organic matter such as manure; mild winters which increase the
number of overwintering stages, especially adult slugs; prolonged periods of
favorable temperatures (63 to 68 degrees) combined with evenly distributed
rainfall that maintains soil moisture at 75 percent saturation; high pH (6.3 -
6.7); over fertilization with nitrogen and cool growing conditions which delay
crop development and extend the period of susceptibility of the crop to slug
injury. You can identify fields with the potential for problems before
planting by placing ten – one square foot boards or roofing shingles throughout
a field and checking under them for slugs. Another sampling method would be to
use a covered pit to provide a humid, sheltered hiding place for slugs. The pit
should be four inches in diameter and six inches deep. An aluminum foil-covered
shingle or a board can be used as a cover to provide a cool refuge from the
sun. Slugs tend to congregate in large numbers in these shelters. As a rule of
thumb, you can expect problems in a field if you find one to five slugs per
trap. Once a field is planted, you should examine fields with a potential for
damage on a weekly basis. If the seed slot is not closed at planting, slugs can
feed underground resulting in reduced stands. Once plants start to emerge, slug
damage will appear as a shredding of the leaves since they feed by grating away
the surface of the plant tissue. The presence of "slime trails"
can also be used to distinguish slug injury. Look for slugs under dirt clods
and surface trash around 5 plants in 10 locations in a field. Since slugs are
nocturnal, sampling should be done in the evening or when weather is cloudy. A
treatment may be needed if conditions are favorable for slug development and
you find 5 or more slugs around each plant from the spike to 3-leaf stage. Although there are no new control options, an
application of 30 percent nitrogen (20 gallons per
acre on corn in the spike to one-leaf stage) or the use of Deadline MPs (metaldehyde bait) should be considered if slugs become a
problem. Nitrogen formulations containing sulfur have been reported to provide
superior control. In 2003, we saw the best results with Deadline MPs. Although
the label states 10 - 40 lbs per acre broadcast, we have seen good results with
10 lbs. broadcast applied with a cyclone spreader. It is important to calibrate
the spreader so you are getting at least 5 pellets per square foot. Also, the
best results have been observed when applications were made and there was at
least one day of sunny weather after an application. In general, slugs stop
feeding in 2-3 hours even though it may take them 2-3
days to die. If conditions remain extremely wet, slugs sometimes can absorb
enough moisture to compensate for the water lost in mucus production so a
second application may be needed.
Timothy.
Cereal
rust mite populations remain low; however, conditions during the next couple of
weeks will determine if we see population explosions. If timothy appears curled
and has a "rusted" appearance, but it is not drought stressed you
should suspect rust mites. The only available control option is Sevin XLR. Apply 3 pts per acre with ground equipment only
with adequate water for complete coverage (20 or more gallons by ground).
One application should provide enough suppression to prevent economic yield and
quality losses. Apply at approximately 3-4 weeks after green-up in fields with
a previous history of rust mites and/or when 25 percent of the plant tillers
exhibit curled tips of the new leaf blades.
More Label Updates for
2004 -
The following herbicide labels have been changed or
modified over the past year. This is
intended to make you aware of changes but be sure to read the labels for
complete details.
Pastures.
Overdrive
70WG (BASF) dicamba and diflufenzopyr (same ingredients as
Distinct). There are no grazing or
harvesting restrictions.
Cimarron
Max (DuPont) a
combination product of
Soybeans.
Gangster
(Valent) Co-packaged
product of FirstRate and Valor. Intended
for preemergence broadleaf weed control with Roundup Ready soybeans.
Do Not Overuse Roundup Ready Corn -
Avoid the temptation to use Roundup Ready corn in
the same fields where you are planting Roundup Ready soybeans. Relying on glyphosate (whether it is Roundup
products, Touchdown, Glyphomax or others) every year for postemergence weed
control is not a sound, long-term weed management program. As a general rule, do not use a Roundup Ready
crop more than once out of two years for a given field.
Height Restrictions for Small Grain
Herbicides -
2,4-D - up to jointing stage (pre-jointing)
Banvel/Clarity - up to jointing stage
(pre-jointing)
Buctril - up to boot stage
Harmony Extra or Harmony GT - up to flag stage
(pre-flag leaf)
Conventional Soybean Herbicides -
I have had some 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.
Grain Marketing Highlights - Carl German, Extension Crops Marketing Specialist; clgerman@udel.edu
April Crop Report Sets Bullish Stage for
Spring Planting.
Good news
abounds in the release of today's USDA monthly supply and demand report. Ending
stocks for
Corn.
Ending
stocks for U.S. corn in the '03/'04 marketing year are now forecast at 856
million bushels, as compared to 901 million bushels estimated last month and
ending stocks of 1.082 billion bushels carried over from the '02/'03 marketing
year. World coarse grain ending stocks now estimated at 102.26 million metric
tons (MMT) are slightly above pre-report trade estimates and slightly higher
than last month's estimate. World ending coarse grain stocks are noted as being
significantly less than the '02/'03 carryover of 145.32 MMT. World corn ending
stocks are now estimated at 67.6 MMT, as compared to 67.79 a month ago and
102.88 MMT carried over from the '02/'03 marketing year.
The
projected price range for
Soybeans.
An
unexpected adjustment was made in U.S. ending stocks for soybeans with the
ending stocks estimate for the '03/'04 marketing year now placed at 115 million
bushels, 10 million bushels less than last month and 63 million bushels less
than the carry over from the '02/'03 marketing year. World ending soybean
stocks for the current marketing year are now forecast at 33 MMT, as compared
to the carry over from the '02/'03 crop of 39.27 MMT.
USDA's
projected price range for
Wheat.
U.S.
wheat ending stocks are now forecast at 531 million bushels, 13 million bushels
less than last month and 40 million bushels more than the 491 MMT '02/'03 carry
over. World ending wheat stocks are now forecast at 127.5 MMT, slightly higher
than the 124.93 MMT projected last month. However, world wheat stocks are significantly
less than the 166.26 MMT carry over from the previous marketing year.
The
projected average price range for
Market Strategy.
Volatile commodity markets are going to be with us for awhile
longer. Any weather problems during '04 crop development will result in large
price moves. Current price offerings, across the board, present some good
opportunities to get some of '04 crop sales locked in. Basis levels for
UPCOMING MEETINGS:
Attention
Vegetable, Fruit & Specialty Crop Growers and All Interested
in New
Enterprises for your Farm
High Tunnel Workshop Series
First of Four Workshops – Constructing
a High Tunnel
Date: Thursday,
April 15, 2004
Time: 3:00 pm—6:30
pm
Place: Blendt Outreach & Research Farm, Delaware
State Univ.,
Directions: Take Rt. 13 to
Information: Contact John Clendaniel 302-857-6425, jclendan@desu.edu
This
workshop is the first of four hands-on workshops that will cover the benefits
of adding a High Tunnel to your operation.
High tunnels are an unheated, protected plasti-culture, growing system. The workshop will explore the layout and
construction of a high tunnel structure.
Future workshops will cover actual use of this structure throughout the
summer with a production system of tomatoes, specialty vegetables, and more. The workshop is organized by the Small Farms
Program of Delaware State University with the cooperation of
Gordon Johnson, Extension
Agent, UD, Kent Co.
Saturday, April 17, 2004
9:00 a.m. – 4:00 p.m.
Course Fee $25
(individual/family); Youth (18 or less) $10
Lunch included.
¨
Honey Bee Biology
¨
Basic Beekeeping Equipment
¨
Honey Bee Diseases &
Parasites
¨
In the Apiary
¨
Care & Feeding of Your
New “livestock”
¨
Where Do We Go From Here??
¨
Time & Labor Saving
Tips/Suggestions
Registration
required. For more Information on the
Program, Contact Dewey Caron,
Week of April 1
to April 7, 2004
|
|
Rainfall: |
|
0.35
inches: April 1 0.01
inches: April 2 |
|
|
|
Air Temperature: |
|
Highs
Ranged from 73°F on April 7 to 46°F on April 5. |
|
Lows
Ranged from 45°F on April 1 to 31°F on April 5 & 6. |
|
Soil
Temperature: |
|
47°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:
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.