Downy Mildew on Pickling Cucumbers – Ed Kee, Extension Vegetable Crops Specialist; firstname.lastname@example.org
Vegetable Crop Insects -
Continue to sample fields for diamondback (DBM) and cabbage looper (CL) larvae. We can also find fall armyworm larvae feeding on plants. A treatment should be considered if you find 5% of the plants infested and before larvae move into the hearts of the plants. If DBM and CL are both present, Avaunt, a Bt, Proclaim or Spintor will provide control. If cabbage looper is the predominant species, a pyrethroid, Intrepid, or Confirm will also provide control.
Lima beans will continue to be extremely attractive to corn earworm moths. Since moth catches continue to be high in black light and pheromone traps, you may need to spray the latest planted fields at least 2 times for earworms. A treatment will be needed if you find one corn earworm larvae per 6 ft of row. Capture, Lannate, Mustang, or Warrior will provide earworm control. The higher labeled rates will be needed if population levels are high and worms are large at the time of treatment. Note – Be sure to always check the label before spraying to determine the pre-harvest interval (number of days between last application and harvest). The pre-harvest interval (PHI) for Warrior on beans is listed incorrectly in the Vegetable Recommendation Guide as a 0 day PHI. The correct PHI is 7 days.
Be sure to maintain a 5-7 day spray schedule for corn borer, corn earworm, beet armyworm and fall armyworm control. Be sure to watch carefully for corn borers and beet armyworm since we are seeing an increase in egg laying activity.
At this time, all fresh market and processing snap beans will need to be sprayed for corn borer and corn earworm control from the bud stage through harvest. Remember, Orthene provides poor corn earworm control. Since trap catches change quickly and corn earworm catches remain high, be sure to check our website for the most recent trap catches and information on how to use this information to make a treatment decision in processing snap beans.
Note – Be sure to always check the label before spraying to determine the pre-harvest interval (number of days between last application and harvest). The pre-harvest interval (PHI) for Warrior on beans is listed incorrectly in the Vegetable Recommendation Guide as a 0 day PHI. The correct PHI is 7 days.
Be sure to scout for webworm and beet armyworm as soon as plants emerge. Controls should be applied when worms are small and before they have moved deep into the hearts of the plants. Also, remember that both insects can produce webbing on the plants. Since beet armyworms are more difficult to control, chemical selection is important. Confirm, Intrepid or Spintor will be needed for beet armyworm control. If webworms are the predominant species, permethrin, Confirm (8 oz/acre), or Intrepid (8-10 oz) should be used. Generally, at least 2 applications are needed to achieve control of webworms and beet armyworm.
With the continued high corn earworm catches and heavy fall armyworm pressure, all fresh market silking sweet corn should be sprayed on a 2 day schedule. A combination of a pyrethroid and Lannate, Larvin, or Lorsban may be needed if pressure from both insects remains heavy until the end of the season. Be sure to check trap catches frequently. You can check trap catches and treatment decision guidelines on our website (http://www.udel.edu/IPM/traps/latestblt.html and http://www.udel.edu/IPM/thresh/silkspraythresh.html).
Field Crop Insects -
With the recent increase in corn earworm trap catches and the presence of webworms, be sure to check fields for signs of defoliators. If a field is 2 or more weeks from cutting and 25-30 percent of the terminals show signs of defoliation or webbing, a treatment is suggested. Baythroid and Warrior are labeled for control of both insects in alfalfa.
In most cases, corn earworm numbers are still low.
We can still find a few larvae but numbers are well below threshold. At this
point, the latest planted fields with blossoms and open canopies will be
attractive to egg laying moths. In addition, we are still catching high numbers
of corn earworm moths in black light and pheromone traps. So, if you have not
scouted your fields be sure to look at them during the next 2 week period since
there are always hot spots of activity that can take us by surprise. A
treatment should be considered if you find
3 corn earworms per 25 sweeps in narrow fields and 5 per 25 sweeps in
wide row fields ( 20-inches are greater).
We are still finding a few beet armyworms and just today a field was
found with economic levels of defoliation. We also hear reports of a few fields
being sprayed in
Weed Control in Seedling Alfalfa -
Getting seedling alfalfa off to a good start is critical for a long-term quality stand. The following herbicide suggestions are for pure alfalfa stands. Gramoxone or Roundup can be used prior to planting to kill emerged weeds. Balan or Eptam can be used pre-plant incorporated for control of small-seeded broadleaves such as pigweed or lambsquarters and most annual grasses. Residual control of either Balan or Eptam is only a few weeks. Butyrac, Buctril, Pursuit, Raptor, and others can only be used after the alfalfa has emerged and developed trifoliate leaves. Fall postemergence treatments include Butyrac 200 ( alfalfa trifoliates), Buctril (at least 4 trifoliates), Kerb, Poast Plus, Select, or Pursuit or Raptor (at least 2 trifoliates). Pursuit or Raptor provides the broadest spectrum of control, and can be tank-mixed with Buctril or Butyrac to improve control. The addition of Buctril to Pursuit will improve German moss, lambsquarters, and henbit control. Kerb will provide the best common chickweed control, but it must be applied when soil temperatures are 50 degrees or less and requires rainfall for activation. Applications to small weeds are critical for effective control. Poast Plus and Select are effective only on grasses, and cannot be used on alfalfa plus grass stands. Most of the labeled herbicides can cause some crop injury to the alfalfa.
Weed Control for Grass or Mixed Pasture Plantings
Weed control options are very limited for establishing a grass or mixed stand pasture. There are no products to use pre-plant incorporated or preemergence that will provide residual control and not injure the crop. Early postemergence options are also very limited. Ally, Banvel, Overdrive, Crossbow, or 2,4-D can be used for pure grass seedlings (they will kill clovers and alfalfa), but grasses need to be well established at time of application. Ally can injure fescue and ryegrass. Fescue injury can be reduced if Ally is tankmixed with 2,4-D.
Options for Harvest Aid Treatments -
A harvest-aid may be a consideration to dry down vegetation prior to harvesting and to reduce foreign matter in the harvested grain. For corn, Defol (sodium chlorate) is labeled for applications 14 days prior to harvest and it can be applied by air. Defol will dry down plants but it does not have herbicide activity. Dry down is slow; expect at least 14 days for dry down. Also, 2,4-D amine is labeled but it must be applied by ground rig, which provides challenges for getting it where it is needed. Apply after the hard dough or dent stage. Air temperatures over 85 can increase the risk of volatility. Glyphosate (Roundup, Touchdown, Glyphomax) is labeled, but must be used with care do to potential injury to desirable vegetation. Apply glyphosate when grain moisture is 35% or less and black layer has formed. Allow 7 days between application and harvest. Gramoxone Max recently received a label for a broadcast treatment. Application rates are 0.8 to 1.5 pts/A and must be applied at least 7 days prior to harvest. Be sure to read the label for all precautions.
Grain Marketing Highlights - Carl German, Extension Crops Marketing Specialist; email@example.com
Commodity Markets; A Moving Target
The corn, soybean, and wheat markets have recently turned slightly bullish from their bearish trends reflected in price bidding at the Chicago Board of Trade (CBOT) just a couple of weeks ago. Why the change? Markets are a moving target. As time passes, price direction and outlook change, reshaping the fundamentals and technical picture. The following reasons are offered by a reliable source as reasons for the somewhat bullish tone to these markets, at the present time:
1. The corn, soybean, and wheat markets have all reacted positively to the mostly negative news contained in the August Crop Report. Each of these markets is trading near or higher than they were going into the report. This is somewhat good news. However, the extent of any continued rally depends in large part to what happens to weather developments prior to mid to the latter part of September.
2. An assumption is that the grain and oilseed markets have discounted a
10.9 billion bushel corn crop and a 2.9 billion bushel soybean crop. Both crops
will have to get bigger from here to push prices lower. The uncertainty lies
within whether that will happen or not? The answer is not likely to be known
fully until we get these crops into the bin. It will be interesting to see how
prices are bid in the corn and soybean pits today. Parts of the
3. All of these markets are showing technical signs of being in the early stages of a turnaround. Consider the following:
a. Corn, soybeans, and wheat have broken through major downtrend lines.
b. CBOT wheat and corn futures charted key reversals up on Monday (8/16).
c. All of these markets are extremely oversold from a technical perspective.
4. These markets have undergone major moves since late spring. Big bull
markets turn into big bear markets and big bear markets, at some point in time,
run out of steam. With these markets reacting positively to overall negative
news it is time to stay on the sidelines for a while longer. Remember, if
an early frost does materialize then that will present an opportunity for those
needing to get additional pre-harvest sales booked. The 'window' on that
opportunity may be short lived considering that the heart of the
*Selected excerpts taken from "The Brock Report".
Delaware Corn Hybrid test is located at the Georgetown Research and Education
Center Farm, near the Chestnut Grove.
UD Corn Hybrid Twilight Field Day
Place: UD Corn Research Plots,
Directions: From Rt. 13, head east on the Smyrna-Leipsic Rd., cross over the Rt. 1 bridge and look for the signs on the left (about ½ mile).
Dinner: A light dinner will be provided
All corn producers are invited to attend
our Corn Hybrid Field Day at the
Gordon Johnson, Extension Agriculture
Week of August 19
0.66 inches: August 21
Highs Ranged from 89°F on August 20 to 77°F on August 22.
Lows Ranged from 73°F on August 20 to 55°F on August 23.
(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:
Extension Associate – Vegetable Crops
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