No. 10
July 7, 2016
Inside this Issue...
Banded Sunflower Moth
EMERGING .............................. 1
Wheat Midge Degree Days Update
................................................ 2
Wheat Midge Trapping ................. 2
Armyworm Damage in Wheat ...... 4
Hail Damage in Soybean ............... 4
Diagnosing the Cause of White
Heads in Small Grains ............. 5
White Mold Review....................... 6
BANDED SUNFLOWER MOTH EMERGING
Pheromone traps ran by the NDSU Extension IPM scouts have
trapped low numbers (<14 moths per trap per week) of banded sunflower
moth in Cass, Barnes and Foster counties. Sunflowers were in late vegetative
to early bud (R1) stages. I’ve also received reports of adult banded
sunflower moth being observed in sunflowers in Canada (Source: Troy
Turner, Agronomist, National Sunflower Association of Canada).
Egg scouting is recommended during the R3 (Immature bud
elongates >2.0 cm above nearest leaf) crop stage. Stay tuned for more
information on banded sunflower moth scouting for eggs and adults and
economic thresholds in the next issue of Crop & Pest Report.
Potassium Deficiency Symptoms in
Certain Soils in Soybean and
Corn ........................................ 8
Galinsoga ....................................... 9
Foxtail Barley Control .................... 9
There Is Plenty of Plant-To-Plant
Variation in Waterhemp ....... 10
Around the State ......................... 11
Northwest ND ............................. 11
Northeast ND .............................. 11
Southwest ND ............................. 12
Weather Forecast: July 7 – July 13
.............................................. 13
Weather/Crop Phenology Maps . 14
Banded sunflower moth adult and eggs above moth.
(Photo by K. Mundal)
North Dakota State University
CROP & PEST REPORT
July 7, 2016
WHEAT MIDGE DEGREE DAYS UPDATE
The current degree day map indicates that most (50-90%) of wheat midge females are emerging this week.
Any wheat in the susceptible crop stages, heading through 50% flowering, should be scouted to confirm sub-threshold
populations are present (read Wheat Midge Trapping article below). See last week article in the Crop & Pest Report #8
for more information about “WHEAT MIDGE DEGREE DAYS FOR SCOUTING.”
Accumulated degree days for wheat midge emergence (base temperature 40°F):
Degree Day Biological Event
Wheat midge breaks larval cocoons and move close to soil surface to form
450
pupal cocoons.
1,100
Males start to emerge
1,300
10 percent of females will have emerged.
1,475
About 50 percent of females will have emerged.
1,600
About 90 percent of females will have emerged.
WHEAT MIDGE TRAPPING
NDSU Extension Entomology is cooperating with Montana State
University on the wheat midge pheromone trapping network using the
PestWeb system. Thanks to the following NDSU Extension IPM scouts who
are monitoring wheat midge traps in North Dakota: Jaime Lundquist
(northeast counties), Hannah Kempler, (north central counties), Taheni
Gargouri (northwest counties), and Taylor Senger (southeast and east central
counties).
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2
Wheat midge trap bottom from
Benson County. Circle shows
parasitoid that kills wheat midge.
(Photo by S. Knoke, Benson Co. Ext.
Office)
North Dakota State University
CROP & PEST REPORT
July 7, 2016
As you can see from the map below, the blue trapping sites indicate low trap counts (below 10 cumulative
midge per trap). Trap counts above 10 midge per trap indicate a risk to wheat midge when the wheat crop is in the
susceptible crop stage – early heading through mid-flowering. The green, gold, orange and red show ascending numbers
of cumulative wheat midge captured. The highest cumulative trap numbers were in near Benson County (gold) last
week. Parasitoids were only found at one trapping site in Barnes County. (The north central area also is trapping for
wheat midge; however, trap data were not available at the time of this posting.) You can assess PestWeb for updates on
trap counts at: https://pestweb.montana.edu/Owbm/Home
If you are above the 10 cumulative midge per trap, we recommend field scouting to confirm the presence of
wheat midge in the field and to determine if populations are at the economic threshold level. The economic thresholds
for field scouting are: one or more midge observed for every four or five heads on hard red spring wheat, or one or
more midge observed for every seven or eight heads on durum wheat. However, the recent heat has advanced the
wheat crop and it is developing quickly through heading to flowering to the milk stage. Wheat is not susceptible to egg
laying by wheat midge females after 50% flowering, because the kernel becomes too hard. Late insecticide
applications are not recommended because the kernel damage is already done if wheat midge was present at economic
populations and the parasitic wasps that kill wheat midge larvae are active then. Additional research is necessary to
refine and validate these trapping data for use in making control decisions for adult wheat midge in wheat fields in
North Dakota.
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
ARMYWORM DAMAGE IN WHEAT
Field reports of armyworm damaging wheat occurred in Barnes and
Ransom counties (Source: B. Christ, Centrol Ag Consulting). The armyworm is
primarily a pest of grasses, small grain crops and corn in North Dakota. The
insect will also attack alfalfa, beans, clover, flax, millet, and sugar beets.
Feeding and movement occur at night or on cloudy days. During the daytime,
armyworms hide under vegetation, loose soil or in soil cracks. Caterpillars
(larvae) consume increasing amounts of vegetation as they grow. Since they
feed at night and hide during the daytime, armyworms often cause
considerable damage before being discovered.
For proper management, it is important to detect and control
armyworms while they are small and before extensive damage has resulted.
Controlling mature larva that have completed their feeding will not achieve
desired results in terms of both control and economic return. Late spraying for
armyworms is often referred to as “revenge” spraying since the crop damage
has been done and no economic benefit is realized.
Initial field scouting for larvae of armyworms should be done in field
margins, low areas, and areas where plants have lodged. Indications of
armyworm feeding include leaf damage, worm frass (droppings) around the
base of plants, and severed leaf material that has fallen to the ground. Look for
larvae beneath plant debris around the base of plants and on heads of wheat
Armyworm larva feeding on wheat
head. (Photo by B. Christ, Centrol Ag
and barley.
Consulting)
Consider treatment if armyworms are ¾ to 1¼ inches long, most larvae
do not exhibit signs of parasitization (white eggs behind the head or small
brown cocoons attached to the body), and leaf feeding or head clipping is evident. If armyworms are more than 1½
inches long, control is not likely to provide economic return.
The economic threshold for armyworms in small grains is:
 Preheading: Treat when four or more worms per square foot are present.
 Heading (head clipping): Treat when two or more worms per square foot are present.
Janet J. Knodel
Extension Entomologist
HAIL DAMAGE IN SOYBEAN
A hailstorm can potentially cause yield losses in soybean ranging from limited yield impact to total destruction of
the crop. Yield loss predictions are based on two factors: a) the growth stage at the time of damage and b) the degree of
plant damage. Plant damage may include leaf defoliation, stand reduction, stem damage and pod damage. The
dominant growing point of the soybean plant is located near the top of the plant. However, there are also growing
points in the leaf axils. If the top of the plant is damaged regrowth can take place form one of more of the axillary buds.
Stand reduction is a measured as the number of plants killed by the storm. Defoliation is measured as a
percentage of the leaf area destroyed by the hail storm. Leaf tissue that is green and still attached to the plant will
continue the process of photosynthesis and is not considered destroyed leaf area. Research has shown that leaf loss
during vegetative stages has limited effect on yield. Defoliation loss is measured only in the reproductive stages and
most soybean plants will be in the reproductive stage starting the first or second week in July.
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
Percent yield loss of soybean varieties as affected by degree of defoliation.
Defoliation (percent leaf area destroyed)
Stage
10
30
50
70
90
100
--------------------------Percent yield loss----------------------------R1-2
0
3
6
9
16
23
R4
3
7
12
22
39
56
R5
4
10
17
31
58
75
R6
1
9
14
23
41
53
Source: Soybean Production Field Guide A1172.
The table provides general guidelines to soybean yield losses due to hail injury. The pod-setting and pod-fill
periods are very susceptible to severe injury. The percentage of nodes cut off or broken were not included in the
calculation of the yield loss. Bean stems may be bruised or broken. The damage may not be severe enough to kill the
plant but the plant may lodge later in the season as the callus tissue is relatively weak and may not support the weight
of the pods.
Hans Kandel
Extension Agronomist Broadleaf Crops
DIAGNOSING THE CAUSE OF WHITE HEADS IN SMALL GRAINS
“White heads” is not the name of a band storming the Billboard charts but a simple description of partially or
completely bleached wheat heads that stick out like a sore thumb in both spring and winter wheat this time of the year.
The following key will help you decipher the most likely cause of these white heads.
Step 1. Is the whole plant white or light green, or is just the head/upper portion of the stem white or lighter
green? If you answer is just the upper portion of the stem, please go to Step 2, otherwise go to Step 8.
Step 2. Pull on the white head and see whether the head and upper most internode, also known as the
peduncle, pulls away from the lower portion of the plant. If you can pull the head and upper most
internode out, go to Step 3, otherwise go to Step 6.
Step 3. Inspect the bottom portion of the peduncle that you pulled out. Does the bottom look like it was cut-off
with a sharp instrument, leaving a clean, precise cut? If yes, go to Step 4, otherwise go to Step 5.
Step 4. The likely culprit is wheat stem sawfly. Wheat stem sawfly is most commonly found in western North
Dakota. Rarely is it an economic pest in other parts of North Dakota or Minnesota.
Step 5. Does the bottom of the peduncle look chewed on and ragged? If yes, the culprit is likely wheat stem
maggot. Wheat stem maggot is common throughout North Dakota and Minnesota. As other grasses can
also harbor wheat stem maggot, incidence of wheat stem maggot can be higher near the field edges.
Nevertheless, incidence rarely, if ever, exceeds 0.5% across a whole field.
Step 6. Inspect the spikes. Do they look off-white as opposed to bleached white? Look for the lowest spikelet
that is off-white white and peel away the outer most glume of this spikelet and the spikelet above it on
the opposing side. Inspect the developing seed. If the seed is chalky white, then the likely culprit is likely
Fusarium Head Blight (FHB). If not or the seed is completely absent, go to Step 7.
Step 7. Inspect there is a pattern and/or gradient across the field. Does the pattern/gradient across the field
coincide with difference in elevation or soil type? If so, go to step 8. If not, the culprit may be glyphosate
drift. Glyphosate drift at very low concentration (less than 2 fl. oz. /acre) can cause sterility if the drift
occurred right around heading.
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
Step 8. The likely culprit is excess water if the worst symptoms coincide with low lying areas or drought stress if
the worst symptoms coincide with higher lying areas or lighter soils. Drought in combination with
temperatures in excess of 92F in the later part of the boot stage or heading stage can cause partial
development of florets and/or sterility, ultimately resulting in poor seed set. Partially or completely
sterile heads tend to ripen faster.
Step 9. Did the whole plant including the crown pull up? If no, go to Step 10, otherwise go to Step 14.
Step 10. Inspect the roots and cut the crown longitudinally. If the crown itself is brown or the stem base has a
honey -colored appearance, and the inside is also brown, then go to Step 11, otherwise go to Step 12.
Step 11. The likely culprit of the white heads is latent common root rot. The initial infection occurred earlier in
the season but was not severe enough to kill the seedling. Instead the plant was able to develop normally
until the demand for water increased to the point where the vascular was no longer able to support the
plant, causing premature death.
Step 12. If the node immediately above the crown is tan/light brown, than the likely culprit is Fusarium Crown
Rot (FCR). Sometimes there a pink color can be found on the leaf sheath or stem base surrounding the
lowest node. This pink color will often disappear once the plant is pulled from the ground and stored for
a few hours. If the roots and crown look black, go to step 13.
Step 13. If the roots, crown and or stem base have a very black appearance, then the likely culprit of the white
heads is take-all. This disease is not common in North Dakota and Minnesota and tends to be found more
in areas where wheat is under irrigation.
Step 14. If the crown did not pull up with the plant, but instead only the stem down to the second internode
looks like it collapsed or has an exit hole on one side, the likely culprit is Hessian fly. Hessian fly is a
relatively rare pest in North Dakota and Minnesota. The highest risk is in winter wheat that is seeded
prior to September 15.
There are a number of other causes of white heads, including feeding by rodents. If you are unsure whether the
problems you are seeing are any of the aforementioned, don’t hesitate to contact your local or regional Extension
educator.
This article was authored by Jochum Wiersma, Madeleine Smith, and Phil Glogoza, University of Minnesota
Extension Service and was originally published in Minnesota Crop News under the title of White Heads and has been
included here with their permission with slight modifications to include issues important in North Dakota.
Joel Ransom
Extension Agronomist for Cereal Crops
WHITE MOLD REVIEW
As broadleaf crops begin to bloom, white mold becomes a concern. Canola is already blooming and most
broadleaf crops will be shortly. Assessing your risk for white mold is very important in managing the disease. I am
modifying an article that I originally posted in last year’s Crop and Pest Report that reviews important information about
white mold.
How does white mold occur?
Sclerotinia survives in the soil as sclerotia; hard, black structures. When there is ample soil moisture, at least 1 to
2 inches of water a week or two before bloom, the sclerotia will germinate, produce apothecia (little mushrooms), and
release ascospores.
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
Once spores are released, they need to land on a nutritional source to begin the infection process; usually the
flower petals. This is the reason that most broadleaf crops are considered susceptible once they begin to flower. Once
the flower petals become colonized, the pathogen easily penetrates the plant and produces the characteristic light tan /
white lesion (it looks like dry bone), takes on a shredded appearance, and black sclerotia are produced.
What are favorable conditions for white mold?
1. Soils need to be moist before bloom. Generally, 1-2 inches of rain falling in a 1-2 week period before
plants enter bloom is the minimum needed for sclerotia to germinate, produce apothecia, and release
ascospores.
2. Moderate temperatures and wetness during bloom. High temperatures above 85 degrees F inhibit
disease. In years where we hit the 90’s F during bloom, we rarely have white mold. Sclerotinia infection
develop best when daytime highs are cooler; 60’s- 70’s.
3. The canopy needs to be wet. Rain, fog, and heavy dews during bloom are all favorable for disease.
Paying attention to the long term rain forecast is important if deciding to make a fungicide application.
4. Canopy density and canopy closure make a big difference on the environment in the field. Once canopy
closure occurs, the crop is likely to have a more favorable environment for infection and disease
development.
5. Although not environmental, crop rotation and white mold history make a difference. A field with a
history or white mold and short rotations among broadleaf crops is more likely to have white mold
problems than a field with no white mold history and/or long crop rotations.
6. Crop makes a difference. Not all broadleaf crops are equally susceptible to white mold. Sunflowers and
dry edible beans consistently seem to be very susceptible, and little resistance is available. Similarly,
canola can be hit hard when the environment is favorable. Soybeans can be infected, but they typically
do not experience the yield loss the other crops do. Additionally, some varieties of soybean are much
less susceptible to white mold than others. Peas can get white mold, but it is less common than other
crops.
How do you manage white mold with fungicides?
Fungicides can help manage the disease and on some crops they can be very effective. Dry bean applications
can be very beneficial in favorable environments; canola application can be as well. Fungicide applications to soybeans
are much more variable and favorable economic returns are less common. Part of the reason is soybeans are naturally
less susceptible that dry beans or canola. Sunflower is very susceptible to white mold, but fungicides are not
recommended because they are generally not effective at reducing disease.
If you choose to make a fungicide application, timing is very important. Applications made relatively early in the
bloom stages are preferred because it helps manage infections that can occur right after the plant enters bloom. In
some cases, canopy closure is a very important consideration that may alter timing strategy slightly. The early infections
tend to do the most damage because they have the greatest time to develop through the season. Later applications may
also prevent infections, but those later infections do less damage.
What resources are available?
Excellent data on white mold applications on soybeans and dry beans and other pathosystems can be found
through the Carrington Research Extension Center website. Carrington has one of the best (perhaps the best) white
mold research programs in the world. I would strongly recommend visiting this site for more information.
The canola sclerotinia risk map uses environmental conditions favorable for sclerotinia, so it can be helpful for
all broadleaf crops.
Sam Markell
Extension Plant Pathologist, Broad-leaf
Crops
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
POTASSIUM DEFICIENCY SYMPTOMS IN CERTAIN SOILS IN SOYBEAN AND CORN
In the drier areas of the state, notably Cass, Sargent and Richland
counties, we have had recent calls and plant sample submission of soybean
and corn exhibiting potassium deficiency symptoms (see images).
Potassium deficiency symptoms on soybean. Leaf
margins affected first on lower leaves. Symptoms
moving up the plant under more severe conditions.
(Jesse Ostrander image).
Potassium deficiency symptoms in corn. Leaf
margins on lower leaves affected first,
moving toward mid-vein and up the plant
under more severe conditions.
Potassium deficiency may be the result of failure to sample in a zone pattern within a field, where the composite
soil sample mixes high K testing soil with low testing soil. In the dry counties, however, the greatest cause is the soil
dryness. In our recent, ongoing, research on potassium (K) on corn, we are finding that soils with a high percentage of
smectitic clays provide K when moist, but draw the K back in when dry. The soils from which these recently distressed
plants come from probably come from fields where the soil is highly smectitic. Soils dominant in illite, such as those in
the Sheyenne Delta region (east of Lisbon, through Walcott, Milnor, Leonard, Colfax, Wyndmere), do not respond very
much to K fertilizer even when soil test K is very low. Illite clays tend to provide K wet or dry. The best cure for K
deficiency symptoms is rainfall, and continually moist, not wet soils. Addition of K as dry 0-0-60, up to 50 pounds of
product per acre, followed by rainfall will help to alleviate serious symptoms in soils where K tests are low, although
some yield reduction has already taken place.
Dave Franzen
NDSU Extension Soil Specialist
8
North Dakota State University
CROP & PEST REPORT
July 7, 2016
GALINSOGA
Question: Any idea what the weed in the photograph below is? Found growing in the Grafton area.
Answer: This plant is galinsoga (Galinsoga parviflora). Galinsoga is in the Composite family and several
herbicides that control composites can control galinsoga.
Photos: Galinsoga (Galinsoga parviflora)
FOXTAIL BARLEY CONTROL
Question: Can you help me plan the correct time and method to control the foxtail barley that has invaded our
pastures. It has migrated from neighboring acreage and because the farmers that own those acres aren't doing enough
to control it, it has become our problem and with each passing year it has becomes more and more serious. In the past,
I've walked one pasture and sprayed each individual plant with glyphosate, but this year we have so much that I can't
possibly do that.
I've been advised that Plateau® is the best chemical for controlling it in pastures. My question is, now that foxtail barley
has begun to produce seeds do we have to wait until next spring to apply Plateau®? Is there nothing other than
glyphosate that can be used at this time of year? Thank you for any help you can give us.
Answer: Foxtail barley continues to grow each year because many do nothing to control it. Management is
difficult in untilled and undisturbed areas.
• Foxtail barley is a perennial bunchgrass, thrives where reduced tillage or no-till is practiced, is native to
North America, is found in wet areas, and is tolerant of saline/alkaline soils.
• Foxtail barley can germinate in the fall or spring. Fall-germinating plants resume growth early in the spring
and have a competitive advantage over spring-seeded crops if not controlled through tillage or chemical
control (EPP or PRE).
• Foxtail barley seeds are primarily spread by wind or can attach to birds or animals for distant distribution.
• Foxtail barley grows 1-2 feet tall and forms a pale green, bushy spike. Leaves are soft to the touch due to
very short, but dense hairs which appear a bluish-green or grayish-green.
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North Dakota State University
•
CROP & PEST REPORT
July 7, 2016
Foxtail barley is easily controlled with tillage because it has a shallow fibrous root system and does not
spread by rootstocks or rhizomes like some other perennial weedy grasses
In 2013, the NDSU Weed Science group
chose foxtail barley as Weed of the Year and the
information was included in the 2013 ND Weed
Control guide.
In summary, glyphosate applied at 1 lb ae/A
(40 fl oz/A of the generic 3 lb ae/gal or 27 fl oz/A of
the Monsanto 4.5 lb ae/gal formulations) from
August to mid-September provided 72-98% foxtail
barley control. Earlier applications and rates lower
than 1 lb ae/A was less effective. The best and most
consistent long-term treatment was glyphosate
applied at 1 lb ae/A after foxtail barley seeds had
matured.
Dr. Brian Jenks, NDSU Weed Scientist,
conducted research on foxtail barley at the North
Central Research and Extension Center, Minot, ND.
Glyphosate spring-applied alone provided only 3568% foxtail barley control. The fall glyphosate application was the most important application given that foxtail barley is
a perennial grass. A photo showing control is included in the report.
Plateau® is labeled for control of foxtail barley (Hordeum jubatum) in pastures, rangeland, and non-crop areas.
The Plateau® label (page 14) identifies foxtail barley as Squirrel Tail Barley (Hordeum jubatum). The label recommends 8
to 12 fl oz/A applied in the spring to vegetative and actively growing foxtail barley. Add MSO type adjuvant at 1% v/v for
increased herbicide enhancement.
Rich Zollinger
Extension Weed Specialist
THERE IS PLENTY OF PLANT-TO-PLANT VARIATION IN WATERHEMP
I received several inquiries last week
about waterhemp. The conversation goes...”
I am nearly certain its waterhemp, but it
doesn’t look quite right”. There is tremendous
diversity in waterhemp, especially waterhemp
that is 12 to 24 inches in size. Plant
architecture, stem color, leaf size and leaf
shape are all unique characteristics of
waterhemp.
Waterhemp tends to be dark green in
color due to surfaces leaf waxes. Stem and
leaf surfaces are smooth and there are no
hairs on the plant. Finally, flowering structures
are open and located near the top of the plant
and at the tips of branches.
Tom Peters
Extension Sugarbeet Agronomist
NDSU & U of MN
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
AROUND THE STATE
NORTHWEST ND
Scattered thunderstorms were still moving through the Northwest last week dropping anywhere from 0.25” to
2” of rain, with most places seeing 0.5” to 1.” A few isolated episodes of hail have been reported. Farmers cutting hay
have noted low yields of both grass and alfalfa hay with some cutting only half the tonnage they were expecting. It
seems that the June rains could not compensate for the dry winter and spring in the first-cut hay crop.
Winter wheat kernels are late dough in many fields and harvest will likely begin next week or the week of the
18th, weather permitting. Winter wheat harvest will likely be a week or two earlier than is normal for our area. Earlyplanted spring wheat and durum are in milk development stages and canola is flowering to late pod. Stripe rust on the
flag leaf of durum and barley has been observed in plots at Williston REC and the crop scout has found head scab on
spring wheat and durum in a few Williams and Divide County fields. Growers are advised to continue to scout for scab in
wheat, especially wheat that is heading or flowering. With more rain in the forecast, fungicide applications may be
necessary in wetter and more humid areas.
Williston REC Field Days are next week! The first is July 14 featuring dryland agronomy and horticulture tours.
The day starts at 8:30 am with lunch provided and an afternoon session on pulse crops. The second is July 15 at our
irrigated Nesson Valley site located 23 miles east of Williston on 1804. The irrigated tour starts at 9 am and ends with
lunch. Please call 701-774-4315 with any questions about field days.
Clair Keene
Area Extension Specialist/Cropping Systems
NDSU Williston Research Extension Center
NORTHEAST ND
In the last two weeks, we are finding low levels of stripe rust in the spring wheat. Much of the spring wheat has
flowered in the region. The scab timing fungicide application will help protect fields from rust infection. June’s turbulent
weather-affected areas are reporting bacterial leaf streak in wheat. Bacterial leaf streak will look bronzy and when
leaves are held up to the light, you may see dried, glossy bacterial exudates on leaves while stripe rust is a bright yelloworange in color. We have also see some general yellow mottling on flag leaves from environmental factors.
Sclerotinia fungicide applications are being applied on canola. The region has three faces this year. We have
farms dealing with summer storm damage –loss due to hail, waterlogging, and disease; farms which are looking
excellent with waist-high corn and green waves of grain; and finally, farms who have been battling uneven emergence or
late stands from spring weather events.
Lesley Lubenow
Area Extension Specialist/Agronomy
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
SOUTHWEST ND
Canola and flax are finishing up blooming. Winter wheat fields
in the region are turning color. There were scattered storms over the
past week that dropped some hail. Most of the region is still dry. From
Tuesday, 6/28 to Tuesday 7/5, NDAWN recorded 0.27 inch of rain in
Bowman and up to 0.46 inch of rain in Dunn County. Some fields are
showing some drought stress.
The Dickinson Research and Extension Center Field Day is
scheduled for the morning of Wednesday, July 13, 2016 at the Center
Headquarters (Big Red Barn Building) at 1041 State Ave, Dickinson, ND.
Speakers begin at 8:50 AM covering topics such as weed identification,
tile drainage, seeding rates in small grains, herbicide resistance,
disease management, and marketing. The event will finish at noon
with a lunch. CEU credits will be available for certified crop advisers.
More information on the field day can be found at the DREC website.
Ryan Buetow
Area Extension Specialist/Cropping Systems
12
A sunflower field north of Glen Ullin, most
sunflowers in the region are in the R1-R3
stage.
North Dakota State University
CROP & PEST REPORT
July 7, 2016
WEATHER FORECAST: JULY 7 – JULY 13
The ridge of high pressure that has been over the southwestern portion of the United States has now shifted
farther to the east and has brought some very warm temperatures to the southern plains. For our region, this
adjustment in the upper level wind flow will allow a trough of low pressure to form over the Pacific Northwest. This
often leads to a more active pattern in the northern plains and that appears to be the case with several rounds of
precipitation projected in the next seven days.
The first round of storms (scattered) should be occurring as you read this (Thursday) with more development
expected Thursday evening and night as well. After some cooler temperatures as of late, once this first wave of
thunderstorms moves through the region, warmer temperatures are expected to return this weekend into early next
week. Those warmer temperatures in combination with a much stronger storm system should produce both more
widespread rain and higher precipitation totals than what is expected for the first wave today. Plus, that second storm
system will send multiple disturbances through the area meaning that at least some part of North Dakota and/or
northwestern Minnesota is expected to receive precipitation from Saturday through next Tuesday. The main wave of
rain and therefore the period of time with the most storms looks to be Sunday Night through Tuesday morning. As is
usually the case, rainfall amounts will vary greatly, but the widespread dry areas will at least have some opportunities
for rain that has been lacking in the past few weeks. Yet, this will also mean that the excessively wet locations in
northeastern North Dakota and far northwestern Minnesota will likely record at least some rain as well. Specifics in
thunderstorms are very difficult to pinpoint beyond a few hours.
Estimated relative humidity (RH) hours are given in Figure 1. With an increase in rain foreseen, plus higher dew
points leading to an increase risk of prolong dew on plants during the overnight hours, RH hours above 85% will
probably be greater than projected in locations that record the higher rainfall totals. The projected Growing Degree Days
(GDDs), base 32°, 44° and 50° for the period July 7 through July 13, 2016 are presented in Figure 2. Although this seven
day period starts cool, with the temperatures expected to be a bit above average this weekend into early next week,
GDDs should overall be near average for the middle of July.
Figure 1. Projected number of Hours with Relative Humidity
above 85% from July 7 through July 13, 2016
Figure 2. Projected Growing Degree Days from July 7 through
July 13, 2016
Daryl Ritchison
Extension Meteorologist
Forecast Blog: ndsu.edu/ndawnblog
(701-231-8209) Twitter: @darylritchison
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North Dakota State University
CROP & PEST REPORT
July 7, 2016
WEATHER/CROP PHENOLOGY MAPS
F. Adnan Akyuz, Ph.D.
Professor of Climatological Practices
North Dakota State Climatologist
http://www.ndsu.edu/ndsco/
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North Dakota State University
CROP & PEST REPORT
NDSU Dept. 7660; PO Box 6050
Fargo, ND 58108-6050
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Janet Knodel, Co-Editor
Entomology
701-231-7915
Sam Markell, Co-Editor
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NDSU Crop and Pest Report
http://www.ag.ndsu.edu/cpr/