Posts Tagged ‘16:14’

WCU Volume 16, Issue 14 – June 20, 2008

Friday, June 20th, 2008

PDF Version of WCU 16:14 – June 20, 2008

In this issue:

Vegetables
Vegetable Crop Insects
Squash Bugs in Pumpkins
Western Flower Thrips on Our Doorstep
Potato Disease Advisory #10 – June 19, 2008
Reflex Can Carry Over to Lima Beans
Vegetable Double Cropping

Agronomic Crops
Agronomic Crop Insects
Test or Scout for Soybean Cyst Nematode
Soybean Rust Update
Field Pansy in Soybeans
Grain Marketing Highlights

Announcements
Recent Topics on Gordon’s Blog
DSU Smyrna Outreach and Research Center Open House
Warm Season Grass Pasture Walk

Weather

Grain Marketing Highlights

Friday, June 20th, 2008

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

Making Grain Sales in a Weather Market
It is becoming more apparent as time passes that 2008 U.S. row crop production will be adversely impacted by the weather and related problems stemming from crop diseases and insects this growing season. The extent of that impact is not known at this point in time. Couple that with high energy prices and the looming energy crisis and it becomes a guessing game as to how high corn and soybean prices could go. Dec ’08 corn futures closed at $7.80; Nov ’08 soybean futures at $15.43; July ’08 SRW (soft red winter) wheat at $9.04; Dec ’08 SRW wheat at $9.45 per bushel; July ’08 crude oil at $137.35 per barrel; and the U.S. dollar index at 73.915 in yesterday’s trading.

USDA’s Actual Plantings Report is due out at the end of the month to be followed by the U.S. and World Supply and Demand reports to be released in early July. Both of those reports will be important in terms of getting a handle on potential ’08 U.S. production. Of equal importance, if not more so, commodity traders will be watching the actions of the U.S. Congress (House and Senate) in terms of dealing with the energy crisis at hand. Oil prices are impacting the prices of everything that we consume. Businesses are finding it extremely difficult to make ends meet and consumers are now feeling the pinch. A comprehensive energy policy is needed to help alleviate the problem. In the event that the U.S. Congress takes action that will increase the supply of energy, then oil futures prices will come down. That in turn is likely to have a negative impact on corn and soybean prices.

Marketing Strategy
One of the best tools (if not the best) for making grain and oilseed sales decisions in a weather market is the use of Agricultural Options on Futures, specifically, the put option. Options are also a proven sales method in extremely volatile markets. A recent case in point is to consider what happened to hedgers in the wheat market this past winter and early spring that were holding short positions in the futures market. Many farmers and commercial hedgers alike could not keep pace with margin calls that at times exceeded the hedge price. Individual farmers lost thousands of dollars. Commercial hedgers lost millions. Just think what would have happened if those positions had been taken in the options market instead? Those hedge sales could have turned a profit rather than a loss. Grain farmers have four primary reasons for considering the use of put options this summer: (1) local grain elevators have restricted the amount that they are willing to book with individual farmers via forward contracts; (2) the high risk of enormous margin calls makes hedging in futures a risky alternative; (3) put options offer an opportunity to establish minimum prices on that portion of the crop not covered by crop insurance; and (4) put options give grain and oilseed farmers the opportunity to make sales at high prices for a known cost up front while locking in a Minimum Sales Price, thereby providing downside price risk protection. Further, in the event of a production shortfall, delivery of the bushels contracted is not required. For further information regarding the use of put options see “How to Reduce Price Risk through Options”, an online PowerPoint presentation, or contact Carl L. German, Extension Crops Marketing Specialist.

Field Pansy in Soybeans

Friday, June 20th, 2008

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

With the cooler temperatures, a number of winter annual weeds are still “hanging around”. One that I have been questioned about is field pansy (or Johnny jump-up). We have tried a number of products to improve control of field pansy, but have not had any success. We have tried Basagran, Reflex, Classic, Pursuit, and others with no additional control over glyphosate alone. Glyphosate may not kill the field pansy, but it will cause some suppression and slow it down. Given that it is so late in June, it will be hard to justify treating a field if field pansy is the only species present since it will soon die (senesce).

Soybean Rust Update

Friday, June 20th, 2008

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

The national picture has not changed since last week. It is dry in Georgia and most of northern Florida, so conditions have not been favorable for spread north yet. On the local scene, all of our sentinel plants have been planted. Some were delayed due to the wet weather but the plantings were made in a timely manner for our region. Plots are located in Sussex County at the Research and Education Center near Georgetown, west of Seaford and near Selbyville. Kent County plots are located near Frederica and Smyrna; New Castle plots are near Summit and at the University Farm in Newark. These will be checked weekly once they begin to flower and every two weeks until then. Two maturity groups are present a Group III and a late Group VII which should stay green until frost.

Test or Scout for Soybean Cyst Nematode

Friday, June 20th, 2008

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

Soybean cyst nematode can be seen on plants that are 32-35 days from planting. The recent dry weather can accentuate the damage from SCN. Look for areas in the field which are yellow and/or stunted. The small yellow or white cysts can be seen easily at this time if you have a 10X hand lens and carefully dig up the plants and do not pull them from the soil. Soil sampling is also encouraged if you do not find the cysts or to confirm their presence if you are not sure. Soil sample bags are available from the county Extension offices. Remember, if soybeans are being planted after barley and wheat it still is not too late to soil test for SCN, especially if you are not planting a resistant variety.

 

Small white female SCN and a large nitrogen fixing nodule for comparison. (SON)

Agronomic Crop Insects

Friday, June 20th, 2008

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

Alfalfa
Continue to sample for potato leafhoppers on a weekly basis. We continue to see an increase in populations – both the adult and nymph stage. As indicated before, the nymphs can cause damage very quickly so sample fields on a weekly basis for both stages. Once plants are yellow, yield loss has already occurred. 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.

Field Corn
Last year we received reports of fields with stinkbug damage to developing ears. In years past, most of the damage we encountered in field corn occurred in the seedling to whorl stage, resulting in stunted and distorted plants. We have started surveying field corn for brown stink bugs and so far populations are sporadic. We did see higher numbers in some wheat fields this spring and there is some evidence from the South that brown stinkbug damage is most severe in corn fields next to wheat fields – that is stinkbugs are moving from wheat to corn. However, we have little experience and data from our area. Reports from Georgia indicate they are seeing higher than normal stinkbug populations this spring. David Buntin, Grain Crop Entomologist from the University of Georgia, provided the following information in his June 2008 newsletter on stinkbug damage in field corn, thresholds and timing of applications in Georgia:

“Stink bugs are back. After low levels the last two years, spring rains have increased bug populations especially brown stink bugs. Corn is most susceptible to stink bug injury during ear formation before tasseling. Bugs will feed through the sheath, causing a dead spot on the ear. As the ear expands it becomes distorted and curves, usually outward. Feeding during silking and pollen shed also will kill kernels on the ear. Once the ear has elongated, stink bug feeding during the blister and milk stages blasts individual kernels, usually causing them to abort.

Recent cage studies at Tifton have found no significant affect on corn grain production at infestation of 1 brown stink bug per plant. The old threshold (5% infested plants) that is in the Handbook is too low. I suggest using a 25% infested plants (1 bug per 4 plants) as a threshold during ear elongation to pollen shed and 50% infested plants (1 bug per 2 plants) during the later part of pollen shed and blister/milk stage. Bug is defined as adults and/or large nymphs. Initially stink bugs tend to be more prevalent on the field edge, so only a perimeter spray may be needed.” Here is the link to his newsletter http://www.caes.uga.edu/commodities/fieldcrops/gagrains/newsletter.html.

Be sure to note that a most of products listed in his newsletter are not labeled in our area on corn ( i.e. Declare, Methyl Parathion, Capture, Brigade, Karate are not labeled in Delaware) so be sure to check all labels for use rates and restrictions. Others can not be used during pollen shed if bees are foraging in the area (Penncap-M).

Soybeans
Be sure to sample fields in the seedling stage for bean leaf beetles, grasshoppers and thrips. We are also seeing an increase in green cloverworm activity, so be sure to scout soybeans for all of these defoliators.

We continue to receive reports of no-till fields that need to be replanted due to slug damage. Unfortunately, this is not unusual due to the fact that soybeans were at a very susceptible stage when slugs are able to do the most damage – i.e. plants were behind in growth and slugs are larger. In addition, the mild winter resulted in an increase in the number of slugs, especially adult stage. Although we had a few hot days last week, spring conditions have been very favorable for slugs (i.e. prolonged periods of favorable temperatures of 63 to 68°F combined with evenly distributed rainfall, maintaining the soil moisture at 75% saturation). As a reminder, tillage will be needed when replanting to allow plants to grow ahead of the damage. The slugs will be less active under hot , dry conditions; however, they will still be present in fields all season and if conditions become cooler and wet again soon after replanting they can still cause damage.

Continue to watch carefully for spider mites. Early detection and control is needed to achieve spider mite suppression. In addition to dimethoate and Lorsban, we now have Hero labeled on soybeans. The bifenthrin component in this mix is the material that will provide spider mite suppression. However, to be effective it should be applied before mites explode. Please refer to the label for use rates and restrictions – you will need the high rate for spider mite control. It should also be noted that the label states do not make applications less than 30 days apart (http://www.cdms.net/LDat/ld80Q005.pdf).

Vegetable Double Cropping

Friday, June 20th, 2008

Gordon Johnson, Extension Ag Agent, Kent Co.; gcjohn@udel.edu

Double cropping season is here and many vegetables will be planted as a second crop behind barley, wheat, peas, early sweet corn, early snap beans, other spring vegetables, and even strawberries. The following are some considerations when double cropping vegetables.

● Crop residue management is critical in order to get a good seed bed for the double crop vegetable. Make efforts to spread and incorporate residue evenly. Heavy areas of incorporated straw or vine will lead to crop variability. Incorporation of high carbon materials such as small grain straw can lead totemporary nitrogen deficiencies. Therefore, extra nitrogen fertilizer will be needed to speed decomposition of these materials (green materials such as pea vines will not cause this problem and will rapidly decompose). It is advised to allow some time (minimum 5-7 days) for residue decomposition before planting the next crop. Allelopathic responses (toxic reactions) in the double crop planting have been found in certain cases when planting has occurred immediately after incorporation of residues.

● Pay close attention to herbicide plant back restrictions. Low rates (0.5-0.75 lbs) of atrazine are often used in sweet corn and this normally does not affect subsequent plantings. However, higher rates can damage the double crop planting. Mesotrione (Callisto), which is used in sweet corn, has significant replant restrictions to many vegetables as does Impact, a related herbicide. Command, Reflex, and Pursuit are examples of other common herbicides with significant plant back restrictions. Check the Delaware Commercial Vegetable Production Recommendation book and the specific herbicide labels for appropriate waiting periods and crops rotational restrictions.

● Some pest problems can be an issue in double crop plantings. Once a crop is harvested, some insects will be seeking a new food source and the newly emerging double crop planting can be at risk. Insects and mites may also move from field margins into the double crop planting. Grasshoppers and two-spotted spider mites would be examples.

● Herbicide programs should be designed to deal with any regrowth issues from the previous crop. Examples would be effectively killing plasticulture strawberries so that vine crops can be double cropped on the beds or dealing with spring brassica crops that went to seed as volunteer weeds.

Reflex Can Carry Over to Lima Beans

Friday, June 20th, 2008

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

There has been some interest in double cropping lima beans behind snap beans treated with Reflex. We have greenhouse and field data to show this is not a good idea. We treated soil with Reflex at 1.5 pts/A and higher rates, and planted lima beans 4 weeks later. We observed both a growth reduction and stand loss with Reflex at 1.5 pts/A. Field cultivation did not improve crop safety.

Potato Disease Advisory #10 – June 19, 2008

Friday, June 20th, 2008

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

 

Disease Severity Value (DSV) Accumulation as of June 18, 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*
5/30-6/1 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
6/12-6/15 1 44 10-day interval 350
6/15-6/18 0 44 10-day interval 376

* 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, 350 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.

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.

Early Blight and Black Dot
Many fields are flowering or have flowered and this is a good time to consider switching to an application or two of Gem, Headline, Quadris, or Evito (no black dot label) for early blight susceptible varieties. This can also be helpful for late season varieties, including russets, if stress makes plants susceptible to black dot later. Make one or two applications at the end of flowering and repeat 14 days later. Apply mancozeb or chlorothalonil 7-days later between the two applications.

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

Western Flower Thrips on Our Doorstep

Friday, June 20th, 2008

Jerry Brust, IPM Vegetable Specialist, University of Maryland; jbrust@umd.edu

I have been working with researchers from Virginia Tech on thrips identification in their crops. They had a severe problem with thrips, especially Western flower thrips (WFT) Frankliniella occidentalis, last summer in tomato and cotton. This year they wanted to see if they were getting early (April and May) populations of Western flower thrips in their fields. Sure enough, the samples I saw from tomatoes, cotton and some winter annual weeds all had 20-50% of their thrips population as Western flower thrips. Southern parts of Maryland and the southernmost part of Delaware will probably see these Western flower thrips populations move into the area in late June and early July. This is another good reason NOT to apply any pesticides to tomato unless absolutely needed, especially early in the season. My research has shown that Western flower thrips are consistently worse on farms in our area that use pesticides on a weekly basis, whether their use is warranted or not. WFT are worse because they are usually resistant to many of the pesticides we commonly use and the frequent sprays greatly reduce natural enemies of WFT. Save your chemical sprays for later in the season when worms, thrips, mites and stink bugs may become major problems.