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Vol. 23, No. 12, June 26, 2008

In this issue

Serious armyworm infestation in Ontario; Soybean aphids; Asiatic garden beetles

Slug-slayer suppliers

Western bean cutworm trapping network starts

Asiatic garden beetles emerging in St. Joseph County - Watch for potato injury in 2008

Potential for nitrogen loss from heavy rainfalls

Are there benefits to using foliar fungicides after hail damage?

Alto fungicide receives Section 3 registration in soybeans

Regional reports

Weather

Next issue: July 10

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Serious armyworm infestation in Ontario; Soybean aphids; Asiatic garden beetles
Christina DiFonzo
Entomology

Armyworm infestation
Ontario is experiencing a serious armyworm infestation in wheat, the worst infestation in decades, with 20-40 larvae per square foot. In some areas, every wheat field has been treated. Caterpillars are now moving from wheat into corn. Ohio State also reported an armyworm outbreak, especially in northwest Ohio last week, but the wheat has progressed far enough that the problem is passing. Michigan appears to have dodged the worst of this problem.

Soybean aphids
Minnesota, North Dakota, Ohio and Wisconsin report soybean aphids colonizing fields, although the numbers are low so far. Interestingly, aphids were observed in both untreated and in early-planted Cruiser-treated fields, probably because the seed treatment was starting to run out. For a current map of aphid detections and my commentary, visit the USDA PIPE web site at http://sba.ipmpipe.org/cgi-bin/sbr/public.cgi. Unlike previous years, this web link directly goes to the aphid map, rather than popping to a soybean rust web site first.

Bruce Mackellar, MSUE Office in St Joseph County, in southwest Michigan reported Asiatic garden beetle adults emerging from fields in his area - see Bruce’s article later in this week’s Cat Alert. Like Japanese beetle, Asiatic garden beetle does feed as an adult. Fortunately, it seems to favor ornamentals, like flowers, over corn and soybean. Unlike Japanese beetle, it is active mostly at night and thus adults may be difficult to observe. Bruce and I are interested in the timing of Asiatic garden beetle egg-laying, especially in potato fields. Any observations are appreciated.

Slug-slayer suppliers
Christina DiFonzo
Entomology

I recently had a call about slug control in ginseng, which brings up slug control in general. Typically, the risk of slug damage is past by early July, but with heavy rain in some locations, combined with crop residue and slow growing conditions, people still may have slug problems. Slug baits with the active ingredient metaldehyde are registered for corn and soybeans (and ginseng!), and they are highly effective. Unlike contact insecticides, which must be sprayed directly onto the pest critter to control it, slugs do themselves in by moving to the bait and feeding.

The most common metaldehyde product is Deadline MPs (MP = mini pellets). A low rate (10-12 lbs per acre) is adequate for field crops. To help assess the reduction in a slug population before and after baiting, I place several old shingles out in the infested field and leave them overnight. Slugs like to accumulate under the flat surfaces during the day, and can be easily counted. Counting before and after baiting can give you a visual check that the treatment reduced slug numbers. Deadline is sold in a 50 lb bag at approximately $2 per pound, meaning a treatment runs $20-$24 per acre. It is sometimes tough to find the product, but the following three Michigan facilities had Deadline MP in stock as of June 26: Wilbur Ellis in Sparta, Helena in Watervliet, and UAP in Sunfield.

Western bean cutworm trapping network starts
Christina DiFonzo
Entomology

In 2006 and 2007, researchers and extension agents trapped a few locations in Michigan for western bean cutworm. In 2006, the first western bean cutworm moth catch ever reported in Michigan was made in Cass County. By 2007, trap catches were reported as far east as Lenawee County and north into Eaton Rapids. However, no damage was reported in southern Michigan. Instead, severe damage to corn was found in northwest Michigan in August, probably as result of a moth flight carried on wind or storm fronts out of Illinois and Wisconsin in July. As a result of the damage and concerns for 2008, the Corn Marketing Program of Michigan funded the purchase of pheromone to trap many more locations. This week and last, cooperators set up traps in many counties, and they will relay their locations back to MSU. We will the enter locations and trap catches throughout the summer onto a public web site maintained by Iowa State University. This web site generates weekly maps of trap captures. As the web site becomes active, we will get the word out in this newsletter and on Farm Radio Network.

In the meantime, for those of you trapping or noticing insects flying at dusk, do not confuse western bean cutworm with the many other cutworm moths in the landscape. Marlin Rice, from Iowa State University, took this great picture of western bean cutworm (Photo 1). Note the distinctive white band at the front margin of the front wing, as well as the white dot and crescent moon in the center of each front wing. He also developed a nice fact sheet on western bean cutworm look-a-likes, available at http://www.ipm.msu.edu/cat08field/pdf/6-26wbc.pdf

Especially don’t confuse western bean cutworm with winter cutworm, the cold-hardy caterpillar menace from last winter. There are numerous reports of this moth flying up as people mow lawns and turn on lights at dusk. This specimen (Photo 2) was sent in recently, and identified as western bean cutworm. Note the lack of white markings in the front wing - instead, there is a black kidney-shaped spot. Moving the front wing aside (Photo 3) reveals a distinctive bright orange hind wing with a black bar - eureka, winter cutworm!


Photo 1. Western bean cutworm moth. Photo credit: M. Rice	Photo 2. Note the lack of white markings in the front wing - instead, there is a black kidney-shaped spot.	Photo 3. A distinctive bright orange hind wing with a black bar helps determine a winter cutworm.

Asiatic garden beetles emerging in St. Joseph County - Watch for potato injury in 2008
Bruce MacKellar
St. Joseph County MSUE educator

Asiatic garden beetle is a new pest in southwest Michigan. The larval stage of this insect was first identified causing root-feeding injury in commercial corn in St. Joseph County and Elkhart County in Indiana in the summer of 2007. The pest contributed to the unevenness that was seen in the corn crop in the extreme southern portion of Michigan during last growing season. Corn fields that were the most severely impacted were rotated fields planted to soybeans the previous year.

During MSUE winter meetings last year, we learned that potato producers in southern St. Joseph County were seeing significant numbers of small grubs showing up in the trucks and at the grading stations as they harvested their later plantings. They reported small pock-marked feeding injury on the tubers, which could occasionally be detected in frying quality tests. Subsequent discussions with the producers and pest managers confirmed that there was activity in the fields with a beetle similar to a Japanese beetle in several potato fields last summer.

We have been closely monitoring Asiatic garden beetle activity in St. Joseph County this spring as part of research initiative funded by Project GREEEN to study how well soil insecticides and seed treatments prevent Asiatic garden beetle grub root feeding and stand loss in commercial corn. We are also conducting a survey to look at how far north the Asiatic garden beetle can be found in significant numbers. Last year, significant damage to unprotected corn was thought to be confined to St. Joseph and eastern Cass counties in Southwest Michigan. Beetles were observed as far north as Battle Creek and West to the Paw Paw area last summer.

This week the first Asiatic garden beetle adults began to emerge. The beetles were observed in a seedcorn field in central St. Joseph County. From the number of emergence channels, I estimate that there were a fair number of beetles in the field. Interestingly, the field was treated with a soil insecticide, and the plants are reasonably uniform in height; no visible signs of damage to the roots could be seen by looking at the growth of the plants. Meanwhile, in potato an agronomist reported finding Asiatic garden beetle adults in several potato fields in the Winamac Indiana area earlier this week. Most of the activity was confined to field edges at this point, but a few fields had high levels of Asiatic garden beetle activity.

MSU Field Crops Entomologist Chris DiFonzo is hoping to develop a method for predicting when Asiatic garden beetle larvae pupate and when adults are likely to emerge. We are looking at both soil and air growing degree day accumulations at the MSU Enviro-weather stations in Mendon and Constantine to chart how these values against adult beetle emergence. It may take several seasons to get a model in place to accurately predict when the adults are likely to emerge.

Chris and Dr. Walt Pett are interested in learning more about when Asiatic garden beetles enter potato fields to lay eggs. Unlike their close cousins, the Japanese beetle, Asiatic garden beetle adults are more active at night than in the daytime. They hope to work with potato producers in St. Joseph County to learn more about the egg-laying behavior of female beetles in potatoes and to monitor development of the larvae to understand when damage occurs and potential ways to prevent it. We are stepping up monitoring activities near soybean and potato fields in St. Joseph County to try to pinpoint when Asiatic garden beetle adults may be moving into fields. Last year, we caught quite a few Asiatic garden beetle adults in milk jug traps set out for western bean cutworm. The thought is that the insects may be attracted to the antifreeze (which is sweet) used in the traps to contain trap the cutworm moths. We will update growers on our findings as the season progresses.

Potential for nitrogen loss from heavy rainfalls
Carrie Laboski
Assistant Professor of Soil Science, University of Wisconsin-Madison, Extension Soil Scientist

Editor’s note: This article was reprinted with permission from the University of Wisconsin. For more information about this article, please contact Carrie Laboskie at 608-263-2795 or email: laboski@wisc.edu

Many soils are saturated and some fields have had or still have standing water in all or part of the field. The million dollar question is: How much nitrogen loss should I expect from denitrification or leaching and what should I do about it? I’ll discuss how to evaluate the potential for nitrogen loss and corrective measures that may be taken.

Denitrification
Denitrification is the process whereby nitrate is converted to the gases dinitrogen or nitrous oxide and subsequently released to the atmosphere. This conversion is carried out by soil bacteria. Denitrification can be a significant mechanism for nitrogen loss on medium- and fine-textured soil. It is generally not an issue on coarse-textured soils because they do not remain saturated for any length of time. There are several environmental factors that determine if denitrification occurs and to what extent.

Nitrate. Nitrate must be present for denitrification to occur. If nitrate is not present or is in low concentrations, denitrification losses will be minimal.
Soil water content and aeration. Denitrification occurs in wet soils with low oxygen concentrations. Denitrification increase with the length of time the soil is saturated. Standing water may result in a greater percentage of nitrate being denitrified.
Temperature. Denitrification proceeds faster on warmer soils, particularly when soil temperature is greater than 75°F.
Organic matter. Denitrification occurs because soil bacteria are breaking down organic matter under low oxygen conditions and the bacteria use nitrate in a biochemical process. Soils with low soluble organic carbon will have less potential for denitrification than soils with high soluble organic carbon. Thus, nitrate that resides deeper in the soil profile (below 12 inches) where there is less organic matter will have a greatly reduced or minimal probability of being denitrified.
Soil pH. Denitrification is negligible in soils with a pH of less than five. Thus, pH likely doesn’t limit denitrification on most of the cropland.

Table 1 shows the combined effect of soil temperature and days of saturated soil on nitrogen loss. Thus, there is the possibility for significant nitrogen loss if soils remain saturated for more than three days.

It is important to keep in mind that nitrate must be present for denitrification to occur. So nitrogen losses will depend on the form of nitrogen that was applied and the time between application and saturated soil conditions. Table 2 provides estimates of the time it takes for various nitrogen fertilizer materials to transform to nitrate. Conversion of ammonium based fertilizers to nitrate takes one to two weeks. Urea must first be hydrolyzed to ammonium before it is converted to nitrate. If a urease inhibitor was used with urea, then the length of time that it takes for urea to convert to ammonium may be extended 10 to 14 days depending upon the rate of inhibitor used. Injection of anhydrous ammonia increases the soil pH for several weeks, which in turn limits the amount of ammonium that is converted to nitrate. If a nitrification inhibitor was used, it will also extend the time it takes for ammonium to convert to nitrate.

Table 1. Estimated nitrogen losses from denitrification as influenced by soil
temperature and number of days the soil is saturated.

Soil temperature ( °F)	Days saturated	Nitrogen loss (percent of applied)
55 to 60	5	10
	10	25
75 to 80	3	60
	5	75
	7	85
	9	95

Table 2. Approximate time until fertilizer N is in the nitrate form.

Fertilizer material	Approximate time until ammonium	Approximate time until nitrate
Ammonium sulfate, 10-34-0, MAP, DAP	0 weeks	1 to 2 weeks
Anhydrous ammonia		3 to 8 weeks
Urea	2 to 4 days	1.25 to 2.5 weeks
Ammonium nitrate	25 percent is ammonium, 0 weeks	25 percent in 1 to 2 weeks 25 percent is nitrate, 0 weeks
UAN	50 percent from urea in 2 to 4 days 25 percent is ammonium, 0 weeks	50 percent in 1.25 to 2.5 weeks 25 percent in 1 to 2 weeks 25 percent is nitrate, 0 weeks

Here’s an example of how to estimate the amount of nitrate that might have been lost. If 120 lb N/a as UAN was applied after planting corn and four days before saturated soil conditions existed and the soil remained saturated for five days, you might expect 20-25 lb N/a to have been denitrified. 120 lb N/a x 25 percent = 30 lb N/a in the nitrate form, assuming minimal conversion of ammonium and urea to nitrate (Table 2). 30 lb N/a as nitrate x 75 percent of nitrate denitrified over five days = 22.5 lb N/a lost. Please note that these are estimates of nitrogen loss, and should not be considered exact.

Another method that could be used to assess the nitrogen status of your fields is to use the pre-sidedress nitrate test (PSNT). If the concentration of nitrogen in this one foot soil sample is greater than 21 ppm, then there should be adequate nitrogen for the crop. There are a couple caveats when using the PSNT in this manner. First, it will work best if nitrogen was broadcast rather than band applied. Soil samples collected from fields where nitrogen was banded, may not accurately represent the nitrogen status of the field. Second, even in medium- and fine-textured soil, nitrate may have moved into the second foot of soil. In this case, the PSNT won’t measure all of the nitrogen that is in the root zone and available for the crop.

If all or most of your nitrogen for corn is coming from an organic nitrogen source (manure and/or forage legume), then the PSNT can still be used to estimate nitrogen credits that are subtracted from your selected maximum return to nitrogen (MRTN) nitrogen rate. Note: when average May-June soil temperatures are more than 1°F below the long-term average, the nitrogen credit is often underestimated.
Where the entire crop nitrogen requirement has not yet been applied, sidedress or other postemergence applications should contain the balance of the crop nitrogen requirement plus 25 to 50 percent of the fertilizer nitrogen that was already applied.

Options for applying supplemental nitrogen when it is needed include traditional sidedressing with anhydrous ammonia or N solutions. UAN solutions can also be applied as a surface band or as a broadcast spray over the growing crop. Dry nitrogen fertilizers (urea, ammonium sulfate, or ammonium nitrate) can also be broadcast applied to the crop. Leaf burning from solution or dry broadcast applications should be expected. Appling the dry materials when foliage is dry will help minimize burning. Broadcast nitrogen rates should be limited to 90 lb N/a for corn with four to five leaves and to 60 lb N/a for corn at the 8-leaf stage. Under nitrogen deficient conditions, corn will respond to supplemental nitrogen applications through the tassel stage of development if the nitrogen can be applied.

Leaching
Nitrate is the form of nitrogen that can be leached when precipitation (or irrigation) exceeds the soil’s ability to hold water in the crop root zone. Leaching is a much bigger issue on sandy soils that typically hold one inch of water per foot of soil compared to medium- and fine-textured soils that hold 2.5 to 3 inches of water per foot of soil. Rainfall totals over the past week likely caused nitrate leaching out of the root zone for potato (18 to 24 inch root zone) and perhaps also corn ( approximately 36 inch root zone) grown on sandy soils. To determine if nitrate could leach out of the root zone, compare the rainfall totals in your area to the number of inches of water that your soil can hold in the crop root zone.

The amount of nitrogen loss from leaching is dependent not only on rainfall, but also on the amount of nitrogen in the nitrate form. Using the information in Table 2, it is possible to estimate how much nitrate may have been leached. For example, if 75 lb N/a as ammonium sulfate was applied when potatoes were planted four weeks prior to the rainfall, and 125 lb N/a as ammonium nitrate was applied three days before the rainfall, then 135 to 140 lb N/a may have leached. The 75 lb N/a as ammonium sulfate at planting would have already been converted to nitrate plus 50 percent of the 125 lb N/a as ammonium nitrate is in the nitrate form = 137.5 lb N/a. The potato crop will have used some of the N that was applied at planting, thus leaching losses will be less than 135 lb N/a

Urea is highly water soluble. If the leaching rainfall occurred before urea had time to hydrolyze (two to four days), then urea may have leached. However, if there were more than four days between urea application and the leaching rainfall, then it is likely that all of the N would have converted to ammonium and remains within the root zone.

Nitrogen best management practices for corn on sandy soils is to sidedress or split apply nitrogen. If sidedress nitrogen applications have not yet occurred, then growers should proceed as planned. If split nitrogen applications have occurred, supplemental nitrogen should be applied and should equal the approximate amount of nitrate that may have leached out of the root zone. Corn grown on irrigated sandy soils are highly responsive to nitrogen fertilization. On non-irrigated sandy soils, water (usually too little) limits crop yield more than nitrogen. Under nitrogen deficient conditions, corn will respond to supplemental nitrogen applications through the tassel stage of development if the nitrogen can be applied.

Many potato fields may have already received their last application of nitrogen fertilizer and are quickly nearing the maximum rate of nitrogen uptake for the crop. Thus it is imperative to make sure that there is adequate nitrogen for the crop. Nitrogen can be applied up to 60 days after emergence; later applications may not improve yield or quality. Supplemental nitrogen application rates could be in the range of the amount of nitrate that was leached from all N applications applied after planting. Monitor the crop’s nitrogen status using the petiole nitrate test to determine if later nitrogen applications may be needed.

For irrigated corn or potato fields, nitrogen solutions can be injected into the irrigation water (fertigation). Water application rates should not exceed the infiltration rate of the soil and should not exceed the soil’s ability to hold the water in the root zone of the crop. Thus, if the soil profile is full of water, you may need to wait a few days before fertigating. The key is to manage the water so that the nitrogen fertilizer that is being applied is not leached.

Are there benefits to using foliar fungicides after hail damage?
Diane Brown-Rytlewski
Plant Pathology

There have been some questions about whether or not fungicides can be of benefit in reducing foliar disease and improving yield when applied to corn after hail damage. A study to simulate hail damage in corn and the effects of fungicide application at tassel emergence was conducted at the University of Illinois last year by Dr. Carl Bradley, plant pathologist in the Department of Crop Sciences. Hail damage was simulated by damaging corn plants with weed-eater type gasoline string trimmer at tassel emergence and applying foliar fungicides the following day. In the trial, foliar fungicides significantly reduced grey leaf spot severity compared to the untreated control in both the simulated hail damage and undamaged plots, but did not significantly affect yield compared with untreated controls. Yields in the simulated hail-damaged plots were significantly lower than those from undamaged plots (Table 1).

Table 1. Effect of simulated hail damage and foliar fungicides applied at tassel emergence on grey leaf spot severity and yield of a susceptible corn variety near Champaign, Illinois, in 2007.

Simulated hail1	Fungicide	Rate/A	GLS severity2	Yield (bu/A)
No	Untreated		57	174
	Headline	6 fl oz	33	179
	Quadris	6 fl oz	42	170
	Quilt	14 fl oz	40	155
Yes	Untreated		62	141
	Headline	6 fl oz	48	144
	Quadris	6 fl oz	47	142
	Quilt	14 fl oz	35	140
		LSD3	12	11

Alto fungicide receives Section 3 registration in soybeans
Diane Brown-Rytlewski
Plant Pathology

United States Environmental Protection Agency (EPA) issued a Section 3 registration for the use of Alto® fungicide in soybeans to control Asian soybean rust. Alto previously had a Section 18 registration. Alto, a systemic triazole fungicide containing the active ingredient cyproconazole is manufactured by Syngenta Crop Protection. Triazoles provide some residual curative activity. More information, including application and rate recommendations for Alto fungicide, is available from your local retailer or sales representative, or by calling the Syngenta Customer Center at 866-SYNGENTA (866-796-4368), or visiting the Syngenta website, http://www.syngentacropprotection.com/labels/ . You can download a copy of the Alto label by clicking here.

Regional reports

1 -- Southeast
Ned Birkey

Weather
Weather has been unsettled with rain almost every day. Locally, heavy showers of up to three inches fell this past Monday, June 23. Hail fell in isolated areas of western Lenawee County on Saturday afternoon and eastern Monroe County on Monday afternoon. Showers are forecast into the weekend, with hot and then cool temperatures forecast.

Crop report
Alfalfa regrowth is doing great. Several farmers are still struggling to get the first cutting baled. Some will have to give up on baling a first cutting and chop it back into the field, as the new growth is coming on fast. Low potato leafhopper numbers are being reported.

Barley fields look good and are turning fast. Barley straw for a non-pesticide pond weed control is a profitable side business for farmers.

Corn is mostly very green with many fields at the V11 leaf stage. Around the four-county-area you can find low spots with water standing and shorter, yellow corn. Fortunately the hail was not widespread and most fields will recover with potentially low yield losses. Stalk bruising may be worse than leaf shredding as diseases may enter the stalk and cause lodging later in the season. European corn borer numbers are lower this week, which indicates that the overwintering generation is coming to an end. Some post-weed control sprays went on too late as weeds were already overtaking corn plant growth. The nitrogen side-dressing plot in Lenawee County was done this past week at the Bakerlads farm for the Center for Excellence.

Oats are heading. I anticipate the wet leaf conditions will be favorable for leaf diseases, which may reduce yields.

Soybeans are struggling a bit with some wet soil conditions. Advanced fields are at the V4 trifoliate leaf stage. Grasses and some broadleaves are growing faster than the beans. Post-emerge herbicide sprays are going on quickly. Some fields look very clean. I found one soybean aphid at the Sentinel plot in Lenawee County this week. Holes in leaves indicate bean leaf beetle feeding, though I could not find any beetles.

Wheat is turning quickly, though the generally cooler temperatures may delay harvest till about July 7. Initially it appears as if there will be Fusarium head scab in some varieties that flowered in moist conditions. At the wheat meeting this past Monday evening, one farmer reported a fifty percent loss due to hail.

Miscellaneous
Farmers are grateful for the weekly and sometimes almost daily rain; some are still short, while others have too much in some fields. Many combines are ready to roll in wheat and several farmers are still planning to double crop soybeans. The MSU Wheat Variety Trial in Lenawee County is still signed for farmers who wish to evaluate varieties. The plot is located on Holloway Road, west of Bucholtz Highway and east of Britton Highway.

2 -- Southwest
Bruce MacKellar

Weather
Unsettled conditions with widely scattered showers and thunderstorms have been the story in southwest Michigan this week. The week started out cooler than normal, but with daytime highs in mid- to upper 80s and high humidity levels in the forecast over the next few days, plant growth should be ready to slip into high gear again. The most significant rainfall has occurred along the Michigan-Indiana border, then moving in a north-easterly direction as the rain heads for southeast Michigan. There has been sporadic hail associated with some of the most severe cells, with a portion of Cass County receiving hail damage from storms on the night of Sunday, June 22. Storms that rolled across St. Joseph County yesterday provided a relatively narrow band of a half inch precipitation. Soil moisture conditions further to the north and west, in particular in portions of Van Buren and Allegan counties, have remained dry over most of this period and could use some precipitation. We are beginning to irrigate seed corn on the Schoolcraft prairie. Base 50 growing degree day totals for areas around the southwest include from May 1 include:

Allegan	733
B. Harbor	727
Kalamazoo	794
Coldwater	765
Lansing	761
Three Rivers	792

Our average heat accumulation is around 18 Base 50 GDD per day at this point in the season. On balance, the heat accumulation is slightly ahead of normal compared to the long term average for the region. In terms of rainfall, only Benton Harbor recorded below normal precipitation over the last four weeks, but most locations listed above are 1.5 to 2 inches behind in rainfall from April 1 compared to normal, and many have been drier than normal in the last one to two weeks.

Crop report
Commercial corn has been on a roll in most areas of southwest Michigan. The most advanced fields are approaching head height, and continue to grow rapidly. Most commercial corn is V7 - V10, with most of the side-dressing completed even on the later planted fields. The first signs of moisture stress are beginning to show up on lighter soils that have missed the recent rainfall, however. Many of the highly irrigated areas have received rainfall, so there has been limited irrigation on commercial corn at this time. We have begun to see Asiatic garden beetle and Japanese beetle emergence. Many growers applied soil insecticides in areas where Asiatic garden beetle white grub pressure had been high in 2007. We have seen much less damage from their larvae this year compared to last. There have been a few spots, however, that have seen damage where soil insecticides were applied in this zone. We continue to see some late emerging grass weeds showing up in corn fields where pre-emergence programs were applied. Common escapes are fall panicum and crabgrass. Small pockets where weed pressure may have gotten ahead of post emergence herbicide applications are fairly common, and have had significant impact on corn color and plant height in those fields. Corn rootworm larvae were expected to reach the 50 percent hatch stage on June 19 in the Mendon area according to one predictive model we are field testing this year.

The seed corn crop is incredibly spread out this year. This is primarily by design, with perhaps some wet planting conditions added to boot over the last couple of weeks. You can find seed corn that is waist-tall, and a nearby field may have been planted last week with corn at V1. From a pest perspective, many seed corn fields were treated for European corn borers in St. Joseph County. The treatments seem to have been effective as there are very few corn borer larvae to be found in most seed fields at this time. Sidedress nitrogen applications along with cultivation the current push for most of the seed corn producers. We continue to see much of the same grass issues in seed corn as in commercial corn, but because of the reduced canopy density, this is more problematic in seed fields. I have not seen any rust or other significant leaf diseases in the few seed fields that I have walked this week.

The early planted soybeans are approaching R1, and they have been growing very well. There have been some challenges with staying ahead of the weeds in beans, and commercial applicators are extremely busy trying to help producers catch up with this task. The crop looks very good at this time. There continue to be fairly sizable numbers of bean leaf beetles in soybean fields in St. Joseph and Van Buren counties. Their populations may bear watching as the crop begins to set pods, where damage from the pest can be more critical. With Japanese beetles beginning to emerge, we can expect to see defoliation on the increase in bean fields soon. I have not seen soybean aphids yet. For whatever reason, there seems to be an elevated number of stink bugs in corn and soybean fields this year. Producers may want to be on the lookout for Asiatic garden beetle activity in soybeans over the next month as well.

In alfalfa, dairy producers were able to harvest second cutting hay in many areas with the small window of good drying conditions. The second cutting quality and yields appear to be excellent in most fields. Potato leafhopper numbers are on the increase, especially over the last few days. Watch your regrowth carefully for potato leafhoppers, because the threshold for treatment is much lower on smaller alfalfa.

The wheat crop is turning and drying down fairly quickly. There have been a few fields that seem to have some bleached heads or at least portions of heads from fusarium head blight, but the degree to which the plants were affected varies widely, probably based on when the plants flowered. The growth of the crop has looked great most of this growing season.

The oat crop has headed out and is producing grain. Yield potential looks good on the few fields that I have looked at this spring.

3 -- West Central
Fred Springborn

Weather
Warm and almost dry could sum up the weather over the last week. Rain showers have been quite light with most giving a trace to a tenth over the last few days. High temperatures were in the mid- to upper 70s. Low air temperatures have been in the 50s. Low soil temperatures have been in the mid-60s

Crop report
Alfalfa regrowth is progressing well. Harvest of the first cutting continues with 80 percent of the crop cut or harvested. Brief light showers have made dry hay harvest a challenge. Fields that have not yet been cut are losing quality to maturity. Early cut fields are regrowing nicely. Potato leafhoppers are present in many fields.

Head scab symptoms can be found in some wheat fields however, many fields have a variety of other disease issues including take-all-disease and frost injury. Both take-all and frost injury can produce heads that appear bleached.

The majority of the corn crop is at the V8 to V10 growth stage. Low levels of armyworm damage have been reported.

Early planted soybean fields are at V4 and most are V3, many fields are still waiting for their first herbicide application.

Dry bean planting is progressing rapidly this week with 80 percent of the crop planted, with rapid emergence and growth where there is enough soil moisture.

4 -- Central
Paul Gross

Weather
The weather has been all over the board this past week. It seems like we have had rainy weather, but have not received much rain. There were scattered showers over the past weekend that brought some hail in isolated areas. It appears the hail caused limited crop damage. For the most part, we have adequate soil moisture, but that will change as crops grow and water use increases.

Crop report
The corn crop is progressing nicely. Most stands are generally good in the central Michigan area and will exceed the “knee high by the fourth of July” benchmark. There is some yellow and purple corn. Most of the weed control and nitrogen applications have been made. Yield potential is very good.

Soybean stands vary greatly. Some are very good, while others have been reduced by frost and excess moisture. Most are in the 3-4 trifoliate leaf stage. Weed control is being applied now that most growers have the corn done. No problems reported at this time. Stands are adequate for normal yields.

The wheat crop is beginning to turn and harvest is about two weeks away. Armyworms have been reported in a few fields in the central Michigan area. There are a few fields that will be treated. At this point, we have not seen signs of head scab, but expect to start seeing symptoms next week if the disease is present.

Harvest of second cutting alfalfa is under way while some are still battling the weather to get the first cutting baled. Growers are reporting very good yields. The growers that are trying to bale are getting frustrated with showers occurring every other day.

Oats and barley are heading and the crops both look very good with no reported problems.

Drybean planting is nearly complete and the early planted beans are emerging.

Sugarbeets are doing very well and are nearly filling the rows.

5 -- Thumb
Bob Battel

Weather
Rains have been light and spotty with 0.25 to 0.50-inch of accumulation across the area. Air temperatures have been warm.

Crop report
Alfalfa looks good. The first cut is generally complete. Expect the second cut to begin during the next week or so. Leafhopper numbers are generally low.

Wheat is also looking good. Some have been spraying for armyworm.

Corn is starting to fill rows. Advanced fields are at the V9 stage.

Soybeans are a bit behind with advanced fields at the fourth trifoliate. Weed control operations are progressing.

Sugar beets are beginning to fill rows at approximately the 14-leaf stage.

Dry bean planting has really ramped up. Conditions are not ideal in all fields, but growers are making good progress. Planting is approximately 80 percent complete, and many plan to complete planting over the next couple of days.

Weather news
Aaron Pollyea
Geography

Shortwave troughs will have the major effect on the state’s weather over the next couple days, producing rainfall across the state. The low should enter our region by Friday, June 27, producing the previously mentioned possible severe weather and rainfall. Rainfall amounts could be more than an inch in central lower Michigan by Friday evening, with more limited rainfall extending across the entire state. The rainfall should persist until Sunday when it will taper off. The warmer temperatures we will be experiencing starting today should persist until Sunday when cooler weather should occur across the state.

Temperatures during the next few days will be generally steady with highs Thursday and Friday ranging from the mid- to upper 70s north to the upper 80s south and lows from the upper 50s to low 60s north to the mid- to upper 60s south. With the shortwave troughs and general cooling occurring, temperatures begin to slide on Saturday, ranging from low to upper 70s across the state, and on Sunday mid-60s to upper 70s. Temperatures then remain in the 70s across the state until Wednesday.

In the medium range forecast, the upper air pattern mentioned above is expected to continue for much of the remainder of June. The National Weather Service 6‑10 day outlook covering July 1 through July 5 calls for near normal temperatures and for precipitation totals to remain at near normal levels. The outlook for the 8-14 day period (July 3- July 9) calls for mean temperatures to range from near normal levels across the state, and for near normal precipitation totals across the state. Further ahead, it is interesting to note that forecast guidance is also hinting that the very turbulent, active upper air pattern of late May and early June may return to the upper Midwest, possibly during early July.

6-26-08