No. 14 August 26, 20108/17/2010) Janet Knodel Extension Entomologist [email protected] TIPS FOR...

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No. 14 August 26, 2010

Inside this Issue...Sulfur and White Butterflies Common . . . . . . . . . . . . . . 1Sap Beetles Damaging Corn Ears . . . . . . . . . . . . . . . . . . 2Pheromone Trap Catches of Banded Sunflower Moth

and Sunflower Moth Decreasing . . . . . . . . . . . . . . . 2Late-Season Grasshoppers Increasing - Scouting

Important . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Hornets/Yellowjackets . . . . . . . . . . . . . . . . . . . . . . . . . . 3Insecticide Update: Bayer Agrees to Terminate

All Uses of Aldicarb . . . . . . . . . . . . . . . . . . . . . . . 3Tips for Planting Winter Wheat in 2010 . . . . . . . . . . . . 4Grant Funding Opportunity for on Farm Research . . . . . 5Soybean Cyst Nematode Survey to Begin in September 6Soybean Cyst Sampling . . . . . . . . . . . . . . . . . . . . . . . . . 6NDSU IPM Field Survey Wrap-up . . . . . . . . . . . . . . . . 6Update on Diseases of Sugarbeet . . . . . . . . . . . . . . . . . . 7Sugarbeet Crop Update . . . . . . . . . . . . . . . . . . . . . . . . . 8New Weed ID Book Available . . . . . . . . . . . . . . . . . . . . 8Scout Fields for Late-Season Weeds . . . . . . . . . . . . . . . 8Last Minute Weed Control Reminders for

Sugarbeet Growers . . . . . . . . . . . . . . . . . . . . . . . . . 9Around the State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Weather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Thank you for your readership of the Crop & Pest Reportin 2010. A wrap-up issue may be published on September9th, if there is enough information to warrant an issue.

Best Wishes for a good harvest!

The Staff and Contributors of the Crop & Pest Report

SULFUR AND WHITE BUTTERFLIES COMMONThere has been some interest in the yellow and white

butterflies flying around in field crops and ditches andwhether they are an insect pest. These butterflies belongto the insect family Pieridae and to the group calledSulphurs and Whites, which are usually white or yellow incolor. Most of their caterpillars are green, usually withone or more pale lateral stripes. Their body surface iscovered with minute hairs, which gives them a velvety

appearance. Larvae of resident species overwinter aschrysalids.

At least 14 species of this group occur in NorthDakota. Common examples include the checkered white(Fig. 1), cabbage butterfly or imported cabbageworm (Fig.2) and alfalfa butterfly (Fig. 3).

Figure 1. Checkered butterfly, female on left and male onright (G. Fauske, NDSU)

Figure 2. Cabbage butterfly female on left and male onright (G. Fauske, NDSU)

Figure 3. Alfalfa butterfly, female on left and male onright (G. Fauske, NDSU)

The cabbage butterfly or imported cabbageworm isattracted to plants in the mustard family (cabbage,broccoli, cauliflower, canola) and can be an occasionalgarden pest. It is typically not an insect pest of canola.The alfalfa butterfly is rarely an insect pest of alfalfa inNorth Dakota. If large numbers of yellow or whitebutterflies are observed flying above alfalfa early inseason, this is a good indication of possible problems laterin the season. Scout fields by sweeping for larvae(caterpillars). An economic threshold level would be 10larvae in one 180 degree sweep.

North Dakota State University CROP & PEST REPORT August 26, 2010

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SAP BEETLES DAMAGING CORN EARSSap beetles (or picnic beetles) have been observed

feeding and damaging corn ears near Jamestown (Fig. 4).

One of the most common sap beetles is Glischrochilusquadrisignatus, which is ¼ inch long, black with fourorange-red spots on the wing covers and has “knobbed”antennae (Fig. 5).

Adult sap beetles feed on decaying, ripening plantmaterial. They are commonly observed feeding onoverripe fruits (raspberries, strawberries) and vegetables(tomatoes). In corn, they typically invade the ear nearinjury sites from birds or other insects. Sap beetles alsoare a nuisance and congregate in large numbers on screendoors of homes, around garbage cans, or picnic areas, oranywhere fermenting plant juices occur. Some sap beetlescarry organisms that cause rots in fruits. There is noinsecticide that provides good control of sap beetles incorn.

PHEROMONE TRAP CATCHES OF BANDEDSUNFLOWER MOTH AND SUNFLOWER MOTHDECREASING

Trap catches for adult banded sunflower moth andsunflower moth have decreased to low levels (Figs. 6 &7). Larvae can now be observed feeding on the sunflowerheads until mid-September. When mature, larvae drop tothe soil to overwinter. However, sunflower moth larvae donot survive the cold winters in North Dakota.

Figure 4. Corn damaged by sap beetles (L. Brower,Stutsman County Extension, NDSU)

Figure 5. Sap beetle, Glischrochilus quadripunctatus (J. Hulcr, MSU, Bugwood.org)

Figure 6. Banded sunflower moth pheromonetrapping map (T. Mittelsteadt, NSA)

Figure 7. Sunflower moth pheromone trapping map(T. Mittelsteadt, NSA)


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LATE-SEASON GRASSHOPPERS INCREASING -SCOUTING IMPORTANT

There have been reports of increasing grasshopperpopulations, especially in western North Dakota. Adultgrasshoppers are very mobile and can fly around to findgreen crops. So, it is important to continue to scout forgrasshoppers in late-season row crops, such as sunflower,corn, flax, etc. When 20 or more adults per square yardare found in field margins or 8 to 14 adults per squareyard are occurring in the crop, treatment would bejustified. In some cases, only field edges need to besprayed to protect fields from grasshopper infestations. Besure to check preharvest intervals before application. Forinsecticide recommendations, please consult the 2010North Dakota Field Crop Insect Management Guide:http://www.ag.ndsu.edu/pubs/plantsci/pests/e1143w1.htm

HORNETS/YELLOWJACKETSThe Extension Entomology office has started getting

calls on annoying hornets swarming or hornet nests inhomes or in trees nearby houses. Hornets (oryellowjackets) (Fig. 8) belong to the family Vespidae.

All yellowjackets sting and their stinging behavior isconsidered a defensive reaction when the colony isthreatened. They can sting more than once because theirstinger stays with the insect. Yellowjackets are moreaggressive during August into September and more likelyto sting people. Although yellowjackets are actually abeneficial insect feeding on other insects, they oftenbecome a pest problem when nests are located nearhomes, schools, picnic areas, or playgrounds. Pest controlis often warranted.

Biology: These wasps are social insects and build nestsof paper-like material. Nests generally resemble ateardrop-shaped soccer ball and often are seen hanging intrees. Sometimes nests are located underground inmammal burrows, cavities or in between house siding. Inthe northern temperate climates, only the mated queenwasp overwinters from the previous year’s colony.

Queens are inactive during the winter, hiding in protectedplaces like under tree barks or attics. In early spring, theoverwintering queen builds a new nest and lays an egg ineach cell. Larvae hatch from the eggs and are dependenton the queen for food. The queen forages outside the nestand brings food (caterpillars and other insects) back to thelarvae until pupation. Sterile female workers emerge frompupae and take over nest building and brood rearing,while the queen stays in the nest. During late summer intoearly fall, adult males and newly produced queens leavetheir parent colony. The colony dies off, and only newlymated queens will find a protected place to overwinter.

Control: Vespid wasps are active outside the nest duringthe daylight hours. Nearly the entire colony is in the nestduring the evening and night-time hours, so controlmeasures should be applied to the nest then. There aremany insecticides labeled for control of hornets andyellowjackets. The difficulty is making the treatmentwithout being stung. Usually an aerosol spray of one ofthe many fast-acting wasp killer will quickly kill allworkers present in nest. Examples are permethrin,synergized pyrethrins or pyrethroid insecticides. Aslower-acting insecticidal approach is to apply carbaryl(Sevin) dust directly onto the exposed nest and entrancehole. After treatment, check the nest for any activity thefollowing day and re-treat if necessary. Nests should beremoved to avoid attracting dermestid beetles at somelater time and to keep wasp pupae from possiblyreestablishing the nest. If dealing with yellowjacket nestsin structures like homes, the nest entrance should never beplugged from the outside. If constrained yellowjacketworkers cannot escape to the outside, they may locate away to escape toward the inside of the home or structure,creating a possible stinging threat for people inside.Yellowjacket nests become an important source of carpetand other dermestid beetle infestations in the home, so thenest should be removed whenever possible. When outsideenjoying your picnic, avoid wearing bright colors andperfumes which are attractive to hornets andyellowjackets.

INSECTICIDE UPDATE: BAYER AGREES TOTERMINATE ALL USES OF ALDICARB

WASHINGTON - The U.S. EnvironmentalProtection Agency and Bayer CropScience, themanufacturer, have reached an agreement to end use ofthe pesticide aldicarb in the United States. A new riskassessment conducted by EPA based on recentlysubmitted toxicity data indicates that aldicarb, an N-methyl carbamate insecticide, no longer meets theagency's rigorous food safety standards and may poseunacceptable dietary risks, especially to infants and youngchildren. To address the most significant risks, Bayer hasagreed first to end aldicarb use on citrus and potatoes andwill adopt risk mitigation measures for other uses toprotect groundwater resources. New measures to protect

Figure 8. Hornet (J. Payne, USDA ARS, Bugwood.org)


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shallow drinking water wells in vulnerable areas of thesoutheastern U.S. coastal plain and lower application rateswill be immediately added to product labels for use oncotton, soybeans, and peanuts.

The company will voluntarily phase out production ofaldicarb by December 31, 2014. All remaining aldicarbuses will end no later than August 2018. Additionally,EPA plans to revoke the tolerances (legal pesticideresidues allowed in food) associated with thesecommodities. EPA did this to ensure we have the safestfood supply possible.

Based upon current toxicological studies, aldicarb atlevels higher than those typically found in food has thepotential to cause various effects such as sweating,nausea, dizziness and blurred vision, abdominal pain,vomiting, and diarrhea.

Aldicarb is registered for use as a systemicinsecticide and nematicide on agricultural crops, and isformulated and marketed solely as a granular pesticideunder the trade name Temik. During the phase-out, thepesticide will continue to be registered for use on cotton,dry beans, peanuts, soybeans, sugar beets, and sweetpotatoes. Aldicarb products are not intended for sale tohomeowners or for use in residential settings. A restricteduse pesticide, aldicarb may be applied only by trained,certified pesticide applicators.

The memorandum of agreement and the agency'supdated dietary risk assessment and supporting materialswill be available in the aldicarb reregistration docket,EPA-HQ-OPP-2005-0163, and in the aldicarb SpecialReview docket, EPA-HQ-OPP-2006-0197, atregulations.gov.

The U.S. has a safe and abundant food supply, andchildren and others should continue to eat a variety offoods, as recommended by the federal government andnutritional experts.

More information:www.epa.gov/oppsrrd1/REDs/factsheets/aldicarb_fs.html

To view the dockets: http://www.regulations.gov

(News Release from EPA Pesticide Program Updates -8/17/2010)

Janet KnodelExtension [email protected]

TIPS FOR PLANTING WINTER WHEAT IN 20101. Plant winter wheat into standing stubble. Survival

of winter wheat during the winter is enhanced when itis covered with snow during the coldest months of theyear. Standing crop residues can effectively retainsnow that may fall. Tall, erect flax and canolastubble works best, but any erect stubble that willretain snow is recommended. Planting winter wheatinto wheat stubble is not ideal for disease reasons, butas long as disease management is planned, wheatstubble can be an acceptable residue.

2. Plant winter-hardy adapted varieties. Use a winterhardy variety, especially if you are not planting intoresidue. Jerry, the latest NDSU release and varietiesdeveloped in Canada are among the most winterhardy varieties currently available. Accipiter andPeregrine are new varieties from Canada that haveproven winter hardiness. Varieties that weredeveloped for Nebraska may not have sufficientwinter-hardiness some years, and should be used onlyif planted into standing stubble and should probablynot be your primary winter wheat variety if you plantany significant acreage. Varieties developed in SDand MT tends to be intermediate in winter hardinessto those developed in ND/Canada and thosedeveloped in NE. Variety performance data from the2009 season are available athttp://www.ag.ndsu.edu/smgrains/ww%20circular%202009.pdf. Table 1 also summarizes data from twolocations in eastern ND for the 2010 season.

3. Apply Phosphorus at time of seeding. Phosphorusfertilization can play a role in winter hardiness,especially if soil tests are low for P. Applying 10-15lbs of P with the seed may improve winter survivalsome years. Excessive N prior to winter freeze-up,however, can reduce winter survival.

4. Plant in September. The optimum planting date forthe northern half of the state is September 1-15 andfor the southern half September 15-30. The lastpractical date that winter wheat can be planted willdepend on the weather since there must be enoughgrowing degree days so that the seed can germinateso that the crop will be vernalized by the spring. Larger seedlings will over winter better than a smallseedling. Target the earlier portion of therecommended planting date range if planting intobare, fallow ground.


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5. Plant 1 to 1.5 inches deep. Adequate moisture forestablishing winter wheat is often a concern as thesoil profile is usually depleted of moisture in the fall. If there is little or no moisture in the soil’s surface,planting shallow (1 to 1.5 inches deep) and waitingfor rain is recommended. Furthermore, theserelatively shallow planting depths allow for fasteremergence when temperatures are rapidly declining.

6. Seed about a million seeds per acre. Generally aseeding rate of 900,000 to 1.2 million viable seed peracre is adequate. The higher seeding rate may beappropriate if planting late or when planting into poorseedbeds. Since winter wheat tends to tiller moreprofusely than spring wheat, 1.2 million seeds peracre is the upper end of the recommended seedingrate. Excessively high seed rates can result in morelodging by harvest time, particularly if you are usinga taller variety (like Jerry).

Table 1. Preliminary yield data from winter wheatvarieties grown in two locations in ND, with and withoutfungicides*, 2010.

Forman ProsperFung No Fung Fung No Fung------------------(bu/acre)----------------

Accipiter 55.1 46.9 49.6 49.8Art 64.7 57.2 71.1 60.6Boomer 56.7 47.5 70.1 59.9Carter 57.2 42.5 64.9 55.1CDC Falcon 57.3 44.3 56.6 51.4Darrell 61.9 58.2 70.1 63.1Decade 54.6 49.3 73.1 65.8Hawken 51.9 47.5 61.9 47.2Jagalene 60.3 39.2 67.4 45.5Jerry 53.7 53.6 73.6 63.4Lyman 55.9 51.8 58.3 50.9Mace 48.4 47.2 55.0 49.2Millenium 65.9 50.3 74.5 69.4Overland 70.5 54.8 76.1 65.4Peregrine 59.8 55.2 68.6 57.3Striker 52.8 48.6 62.6 58.4Wesley 58.5 44.0 61.0 56.5Yellowstone 47.2 35.3 60.8 47.6Average 57.4 48.5 65.3 56.5

*At Forman, fungicides consisted of Stratego™ at the 4 lf stageand Prosaro™ at flowering, while at Propser, Prosaro™ wasapplied only at flowering.

Joel RansomExtension Agronomist for Cereal Crops

[email protected]

GRANT FUNDING OPPORTUNITY FOR ONFARM RESEARCH

The small grain harvest is winding down and cornand soybean crops are not yet ready for combining. Thiswould be a good time to think about the 2011 season.Most producers have great ideas to improve their farmingpractices. On farm research on new practices is a greatway to learn and explore new ideas.

The 2010 North Central Region - SustainableAgriculture Research and Education Program (NCR-SARE) Farmer Rancher Grant Call for Proposals is nowavailable specifically for research ideas related tosustainable farming. Many North Dakota producers areinterested in reducing tillage of the fields, incorporatingcover crops and other new farming practices. Farmers andranchers in the North Central Region, which includesNorth Dakota and Minnesota, are invited to submit grantproposals to explore sustainable agriculture solutions toproblems on the farm or ranch. Proposals should showhow farmers and ranchers plan to use their own innovativeideas to explore sustainable agriculture options and howthey will share project results with other producers.Projects should emphasize research, education ordemonstration. Grants can range from $6,000 forindividual farmers up to $18,000 for groups of three ormore farmers.

NCR-SARE expects to fund about 50 projects in thetwelve-state North Central Region for the 2011 productionseason. The funding will be available in the spring of2011 in time for research during the cropping season.Interested applicants can find the call for proposals online,as well as useful information for completing a proposal, athttp://www.sare.org/NCRSARE/cfp.htm. Proposals aredue on Thursday, December 2, 2010 at 4:30 p.m. at theNCR-SARE office in Jefferson City, MO. Potentialapplicants with questions can contact Joan Benjamin,Associate Regional Coordinator and Farmer RancherGrant Program Coordinator, at [email protected] or 800-529-1342.

Each state in SARE's North Central Region has aState Sustainable Agriculture Coordinator. In NorthDakota the coordinator is Frank Kutka([email protected] or 701-483-2348, ext 113), whocan provide information and assistance to potential grantapplicants. Producers are encouraged to work withextension agents and other agricultural professionals todevelop a strong proposal. The projects will be evaluatedby farmers and professionals working in agriculture.

Hans KandelExtension Agronomist Broadleaf Crops

[email protected]


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SOYBEAN CYST NEMATODE SURVEY TO BEGININ SEPTEMBER

Soybean cyst nematode (SCN) is the most importantsoybean disease in the United States. In North Dakota, thedisease is emerging, and has been confirmed in only threecounties; Richland, Cass, and Dickey. However, thedisease may be more widespread.

In an effort to determine how widespread SCN hasmoved we are collaborating with the National AgricultureStatistics Service (NASS) and the North Dakota SoybeanCouncil (NDSC) to conduct a survey beginning nextweek. NASS enumerators will soil sample for SCN inapproximately 120 soybean fields throughout the state. The soil will be processed at the plant diagnostic lab atNDSU, and the data will be presented at winter meetings. Only county wide data will be presented.

This information will help us understand where SCNis in the state and increase awareness of this criticaldisease.

SOYBEAN CYST SAMPLINGSCN is a threat to soybean producers in North

Dakota. The disease can cause up to a 30% yield lossbefore above ground symptoms are present. Further, it isoften hard to decipher those symptoms from other issues,such as IDC. The best way to detect the pathogen isthrough soil sampling, and the best time to soil sample forSCN is at the end of the season, including after harvest.

I would encourage soybean growers in ND,particularly those in the SE part of the state, to sampletheir fields for SCN. There are multiple labs that canprocess soil samples, commercial and University both. The most important aspect to management of SCN is earlydetection of the pathogen. IF SCN levels get high,successfully growing soybeans in the near future will bedifficult. However, if SCN is detected before thepopulation is high; the disease can be managed withresistant varieties and rotation.

For sampling instructions, many good resources areavailable. An excellent publication produced by the NorthCentral Soybean Research Program is available at thePlant Health Initiative websitewww.planthealth.info/pdf_docs/SCN_Management.pdf A video produced by Iowa State University is available athttp://www.youtube.com/watch?v=W2GCGnOcGWs

Sam MarkellExtension Plant [email protected]

NDSU IPM FIELD SURVEY WRAP-UP The NDSU IPM field scouts have finished up their

field scouting for the year, either going back to school orcontinuing with other jobs. Many thanks to Dixie Denis,Richard Glatt, Ryan Grieger, Suanne Kallis, and AsungaManamperi for their scouting efforts this year. Andthanks to James Walker, IPM mapper, and Roger Ashley,Greg Endres, Jan Knodel, Carrie Larson, Sam Markell,Lionel Olson, and Dan Waldstein for giving guidance tothe scouts.

The scouts surveyed 810 wheat fields, 59 barleyfields, 189 sunflower fields, 197 soybean fields and 56canola fields during the growing season. Soybean andcanola were surveyed primarily for insects. The scoutsalso put out insect traps in canola, sunflower and wheatfields. The following is a brief summary of the diseasesthe scouts found in wheat, barley and sunflower. Maps ofthe various pest occurrences each week and seasonsummaries may be found at:

http://www.ag.ndsu.nodak.edu/aginfo/ndipm/

Wheat: Leaf rust: Only 3.4% of scouted fields showedsymptoms of wheat leaf rust, and those fields had anaverage 3% leaf severity. Slightly more of the surveyedfields showed symptoms of stripe rust in 2010, with 4.7%of surveyed fields showing symptoms. Field severity ofstripe rust was not measured, as it usually is a rarelyobserved disease.

Tan spot fungal leaf disease was by far the mostcommon disease observed in wheat in 2010, with over90% of fields showing symptoms, and an average severityof 3.4%, but a range of 1 to 45% leaf severity. Anotherfungal leaf spot, Septoria, was observed in 9% ofsurveyed fields with 1.9% average severity.

Barley yellow dwarf virus symptoms were observedin 2.7% of surveyed fields, while wheat streak mosaicvirus symptoms were observed in 7.8% of surveyed fields. Bacterial leaf streak was observed in 6% of surveyedwheat fields.

Post-heading diseases observed included loose smut,found in 12.7% of post-heading fields, with an average of6.5% of tillers infected - well above a seed treatmentthreshold in those infected fields. Head scab, or Fusariumhead blight, was observed in 18.3% of post-floweringfields surveyed, with an average field severity of 4.1%. Glume blotch and/or bacterial black chaff were observedin 6% of post-heading fields.

Barley: The field scouts reported primarily fungal leafspot diseases in barley. They observed net blotch, spotblotch, and/or Septoria in 64% of surveyed fields. Somefields had a combination of these leaf diseases present. The average severity of these leaf spot diseases was 8%.


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Sunflower: Of the 189 sunflower fields surveyed, 30%showed symptoms of downy mildew. The averageincidence of downy mildew infected plants in these fieldswas 4%. Sunflower rust was observed in about 21% ofthe surveyed fields with an average severity of about 1%.

Marcia McMullenNDSU Extension Plant Pathologist

[email protected]

UPDATE ON DISEASES OF SUGARBEETSome of the common diseases that affect sugarbeet

include Cercospora leaf spot, Fusarium, Rhizomania, andRhizoctonia crown and root rot.

Cercospora leaf spot is the most damaging leafdisease of sugarbeet in our area. It is caused by thefungus Cercospora beticola which does most damage inwarm weather (80 to 90 degree days and over 60 degreesin the night) and when it is rainy or when we have heavydew. The fungus destroys the leaves that are responsiblefor making the sugar in the plant resulting in reducedtonnage and lower extractable sucrose.

Growers, over the years, have done a good job ofmanaging Cercospora by using crop rotation, tolerantvarieties, and fungicide applications. During the past fiveyears, inoculum pressure in growers’ fields has been lowand continues to be low in most areas. In a number offields, there was no leaf spot. However, in several fields,individual plants with lots of disease are randomlydistributed and serve as inoculum source. Some of thesefields will need multiple applications at a minimum of 14day intervals to control the disease. The fungicides whichare currently most effective at controlling Cercospora leafspot in fungicide trials at Foxhome are Proline, Inspire,Headline and a mixture of Topsin and Super Tin. Scoutingof fields should continue – scouts should look for heavilyinfected plants scattered throughout the field.

The best way to control Cercospora leaf spot is toapply fungicides in a timely manner. For groundapplication, apply fungicides in 20 gallons of water peracre at 100 psi pressure; aerial applicators should use 5 to7 gallons of water per acre for best results. Use therecommended rate of the fungicide; cutting rates willresult in poor disease control and will quickly lead to thedevelopment of resistant isolates.

Fusarium yellows were first observed very early atthe Moorhead research. Symptoms include interveinalyellowing and death of older leaves, sometime distinctdeath of half the leaf on one side of the midrib, followedby death of the younger leaves. When the roots ofinfected plants are cut in a cross section, there is a distinctdarkening of the vascular system. Roots of infected plantswill not store well in piles. The best way to manageFusarium yellows is to plant tolerant varieties.

Plants infected by the Necrotic Yellow Vein Virus,which causes Rhizomania, are easy to observe in fields atthis time. Plants infected with Rhizomania have distinctly

fluorescent yellow-green leaves with hairy adventitiousroots. The best way to manage Rhizomania is to plantresistant varieties. Therefore, in fields with a history ofthis disease, use resistant varieties approved for yourfactory district. Please note that all Roundup Readyvarieties are resistant to Rhizomania. However, for fieldswith a known history of Rhizomania, check with youragriculturists, consultants, and seed companyrepresentatives for varieties that will perform well inheavy Rhizomania conditions.

Rhizoctonia solani causes Rhizoctonia crown androot rot of sugarbeet and root rot is becoming moreprevalent, probably because of planting into warmer soilsthat have remained wet most of the season. Rhizoctoniasolani can infect sugarbeet at all growth stages and resultsin wilting and death of plants. The fungus causes infectionwhen soil moisture range from somewhat dry to wet andsoil temperatures above 65 F. The fungus typically causesdamping-off, and crown and root rot of sugarbeet.Damping-off occurs at the seedling stage when the fungusinfects the hypocotyls resulting in rapid collapse ofseedlings before soil emergence or post-emergence.Damping-off affects the plant population and ultimatelyreduces the yield. Crown and root rot infection occurs inolder plants when the pathogen infects the petioles or theroots. Characteristic symptoms of Rhizoctonia includesudden wilting of leaves, and petioles of outer leaves maybe blackened at the point of attachment to the crown. Crown and root rots, separately or collectively, are themost damaging phase of the disease and reduces yieldsignificantly. The disease may also produce dry rotcankers on the root surface.

Fields with a known history of severe Rhizoctoniashould be planted to a tolerant variety. Crop rotation witha non-host, namely wheat, early planting, proper drainage,and avoidance of throwing soil into crowns of plants atcultivation will assist in managing the disease. The use ofthe fungicides Quadris or Proline at the 4 to 6 leaf stage orwhen the soil temperature at the four inch depth is about65 F will also help to control Rhizoctonia crown and rootrot.

There are also fields infected with Aphanomyces rootrot. Warm and wet soils provide favorable conditions forinfection by the fungus Aphanomyces cochlioides. Infields with a history of this disease, growers should usetolerant varieties treated with Tachigaren.

Growers need to plan management strategies early tomanage diseases – planning should start with field andvariety selection. Fields that has diseases at this timeshould be recorded so that appropriate varieties will beselected the next time these fields go into sugarbeet. Scoutfields when necessary so that fungicides are applied in atimely manner, and when necessary, shorten the fungicideapplication intervals to prevent Cercospora leaf spot fromcausing an economic loss.


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SUGARBEET CROP UPDATEEarly planting, adequate moisture, and favorable

growing degree days have resulted in an excellentsugarbeet crop. Although the weather conditions werealso favorable for many diseases of sugarbeet, the currentsugarbeet crop will likely be the largest ever harvested. American Crystal Sugar Company and Minn-Dak FarmersCooperative have their earliest start to harvest ever –August 17. Growers in southern Minnesota will startharvest on September 23. During pre-piling, about 15%of the crop will be harvested. The full harvest campaignwill start on October 1. Please follow all safety rules atharvest and when transporting and piling beets.

Mohamed KhanExtension Sugarbeet Specialist

NDSU and University of [email protected]

701-231-8596

NEW WEED ID BOOK AVAILABLE

Weeds of the Midwestern United States & Central CanadaEdited by Charles T. Bryson and Michael S. DeFelicePublication date: July 1, 2010Flexibind w/ flaps, $44.95 | ISBN 978-0-8203-3506-3440 pp.; 1423 color photos | 363 maps

This weed ID book features more than 1,400 full-color photographs, 363 maps on 440 pages and this handyguide provides essential information on more than 350 ofthe most troublesome weedy and invasive plants found inthe midwestern United States and central Canada.Drawing on the expertise of more than forty weedscientists and botanists, the guide identifies each plant atvarious stages of its life and offers useful details about itsorigin, habitat, morphology, biology, distribution, andtoxic properties. The book also includes illustrations ofthe most common characteristics of plants and terms usedto describe them, a key to plant families included in thebook, a glossary of frequently used terms, a bibliography,and indexes of scientific and common plant names. This isan essential guide for agronomists, crop and soilscientists, horticulturists, botanists, Cooperative ExtensionService agents, farmers, gardeners, students in agricultureand biology, lawn care professionals, green industryprofessionals, nursery owners, government quarantineworkers, and land preservationists.

Each species account includes:• Distribution map and up to four color photographs

showing seed, seedling, plant & flower• Scientific names, common names, and local

synonyms of common names• Vegetative characteristics for seedlings and leaves• Notes on special identifying characteristics,

reproductive characteristics, and toxic properties

Covers Illinois, Indiana, Iowa, northeastern Kansas,northern Kentucky, southern Manitoba, Michigan,Minnesota, northern Missouri, eastern Nebraska, North Dakota, Ohio, southern Ontario, southwestern Quebec,southeastern Saskatchewan, eastern South Dakota andWisconsin.

Rich ZollingerExtension Weed Specialist

[email protected]

SCOUT FIELDS FOR LATE-SEASON WEEDSScout crop fields for weeds before harvest to

determine the effectiveness of this year’s herbicideprogram. If weeds are present determine why they arepresent. There are many reasons for weeds to be presentat this time of the year in crop fields. If weeds are presentdue to herbicide resistance, it is important to know soonerthan later. The presence of 6 to 12 plants survivingherbicides in a field will make future weed managementmore difficult.

A video is available to assist in scouting forglyphosate-resistant weeds. The video can be found byvisiting the following internet address and clicking on“Scouting for Glyphosate Resistance”: http://www.ag.ndsu.edu/weeds/herbicide-resistant-weeds. This video is helpful in scouting for low-level resistanceto any herbicide. Seventy-five percent of fields predictedto have glyphosate-resistant common ragweed based uponindividual plant response demonstrated in the video wereconfirmed to have resistant ragweed.

The most accurate way to confirm herbicideresistance is to collect seeds from suspected plants andconduct greenhouse research comparing the suspectedpopulation to known resistant and susceptible populations. If you suspect glyphosate-resistant weeds in RoundupReady sugarbeet, soybean, or corn, contact Jeff Stachler [email protected] or by phone at 701-231-8131(office) or 218-790-8131 (cell).

Pulling/cutting surviving plants, removing them fromthe field, and destroying them should reduce the spread ofresistant plants. If glyphosate-resistant weeds are suspectedprepare a diverse weed management plan for next season toreduce the spread of glyphosate-resistant weeds.


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LAST MINUTE WEED CONTROL REMINDERSFOR SUGARBEET GROWERS

Remove all bolting beets from Roundup Readysugarbeet fields as soon as possible. Allowing these beetsto produce seed can cause a future weed problem in futureRoundup Ready crops.

Consider harvesting all or parts of the weediestsugarbeet fields during this pre-pile period. Destructionof weeds during the topping process at this time of theyear should reduce weed seed production compared towaiting until the piling period of harvest.

Jeff StachlerAgronomist - Weed Science

[email protected]

South-Central ND

According to NDAWN (North Dakota Agriculture Weather Network) data, the region received 1.2 inches(Robinson) to 4.3 inches (Pillsbury) of rain during August1-24. According to NDAWN, corn water use during theweek of August 18-24 averaged 0.10 to 0.15 inches perday. The past weekend’s warm weather and wind hashastened the development of row crops.

The majority of spring wheat acres have been harvested(> 75%). Preliminary harvest reports indicate wheat yieldaveraging in the mid 50 to 60 bu/acre range and adequateprotein levels. Most of the region’s corn is in the dent(R5) growth stage, thus 2-3 weeks are required to reachphysiological maturity. Dry beans are near or are at seedmaturity, and field chemical desiccation is in progress.Soybeans generally are in the full seed (R6) stage, withsome early-maturing varieties at initial maturity (R7).White mold is becoming more common in soybean fields.This is a good time to scout soybean fields for all diseasesin preparation for future field disease management plans.Yield potential for corn and late-season broadleaf cropscontinues to be positive.

ROW CROP TOUR ON SEPTEMBER 2, 2010The NDSU Carrington Research Extension Center’s

annual row crop tour, featuring production research andrecommendations for corn, dry bean, soybean andsunflower is scheduled for September 2. The tour willbegin at 3 p.m. with dry bean and sunflower, continues at5 p.m. with corn and soybean, and concludes with asponsored supper.

Refreshment and meal sponsors are the North DakotaSoybean Council, National Sunflower Association andNorth Dakota Corn Growers Association and UtilizationCouncil. Each organization has been invited to providebrief updates on its activities during supper.

Four continuing education credits will be availablefor certified crop advisers.

Additional information about the tour is availablefrom the Carrington REC at(701) 652-2951 or atwww.ag.ndsu.edu/CarringtonREC/events.

Greg EndresArea Extension Specialist/Cropping Systems

NDSU Carrington Research Extension [email protected]


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F. Adnan Akyüz, Ph.D.Assistant Professor of Climatology

North Dakota State Climatologisthttp://www.ndsu.edu/ndsco/

North Dakota State UniversityCROP & PEST REPORTNDSU Dept. 7650; PO Box 6050Fargo, ND 58108-6050

Sam Markell, Co-EditorPlant Pathology231-8866 phone231-7851 fax

Janet Knodel, Co-EditorEntomology231-7582 phone231-8557 fax

Plant Sciences231-7972 phone231-8474 fax

Soils231-8881 phone231-7861 fax

Weeds231-7972 phone231-8474 fax

Ag Engineering231-7261 phone231-1008 fax

Helping You Put Knowledge To WorkThe information given herein is for educational purposes only. References to a commercial product or trade name is made with theunderstanding that no discrimination is intended and no endorsement by the North Dakota Extension Service is implied.

NDSU Extension Service, North Dakota State University of Agriculture and Applied Science, and the U.S. Department of Agriculturecooperating. Duane Hauck, Director, Fargo, North Dakota. Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914.We offer our programs and facilities to all persons regardless of race, color, national origin, sex, handicap, age, Vietnam era veteransstatus, or sexual orientation; and are an equal opportunity employer.This publication will be made available in alternative formats for people with disabilities upon request (701) 231-7881.

NDSU Crop and Pest Report http://www.ag.ndsu.nodak.edu/aginfo/entomology/ndsucpr/index.htm

No. 14 August 26, 20108/17/2010) Janet Knodel Extension Entomologist [email protected] TIPS FOR...

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