The Minnesota Department of Agriculture (MDA) is preparing to treat approximately 1,751 acres of land in Winona County to slow the spread of a gypsy moth infestation identified last year. Officials will conduct the aerial treatment sometime between June 22 and June 29, beginning as early as 7:00 a.m. This date is dependent on weather conditions in the area leading up to the treatment date.
The Minnesota Department of Agriculture will be spraying the Pine Creek area of Winona County in Minnesota to slow the spread of the gypsy moth into the state’s tree forests. (photo from hatfieldspraying.com)
To help area citizens stay informed, the MDA has set up an Arrest the Pest information line at 1-888-545-MOTH (6684). The hotline will offer the latest details about treatment date and time.
The MDA maintains a monitoring program to watch for start-up infestations. When an infestation is found, the department conducts aerial treatments of the infestation before it can spread. In 2016, the MDA found an infestation in New Hartford Township, Winona County (referred to as the Pine Creek block). (SEE MAP) Details of the area can be found at www.mda.state.mn.us/gmtreatments.
The MDA will use a method of mating disruption involving the aerial application of a waxy, food-grade substance containing a pheromone that confuses male gypsy moths. This makes it difficult for the male gypsy moths to find females for mating, which means fewer caterpillars hatching and attacking trees next year. The application is timed just as adult moths emerge in mid-summer.
Mating disruption has been widely used for gypsy moth management in Minnesota and across the nation. It is an effective tool that helps slow the spread of the insect as it moves westward across the country. Minnesota has benefited greatly from the use of mating disruption in Wisconsin and other eastern states that have kept new gypsy moth populations at bay.
This work is being coordinated through the national Slow the Spread of Gypsy Moth program directed by the U.S. Forest Service. Minnesota has been part of this program since 2004. These efforts protect forest health, property values, and the state’s tourism industry.
Gypsy moths are among America’s most destructive tree pests, having caused millions of dollars in damage to Eastern forests. If present in large numbers, gypsy moth caterpillars can defoliate large sections of forest.
“Yes, things are looking good,” said Miller. “The one strange thing is the fields that were planted in early May typically aren’t showing rows anymore, and we can still see them. There are some places where you can still see down to the soil surface, which is extremely odd at this point, unless it was a really late planted field. That peaked my interest.”
He added, “They could still potentially close, and we’ll be following up in the next week or two to see what happens.”
The other challenge in soybeans is disease pressure in certain fields.
He are soybeans showing the symptoms of sudden death syndrome, which is said to be showing up in south central Minnesota bean fields. (Photo from Pioneer.com)
“It appears sudden death syndrome is starting to poke its head up,” said Miller. “We’re starting to see the symptomology. We should start to see more of it in the next couple of weeks. Right now, unless you’re out in the fields, it’s hard to see the foliar symptoms. If you’re on the road, you probably won’t pick it up.
“Unfortunately, there is a history of SDS in the area, basically from Waseca to Owatonna, and Austin to Albert Lea,” said Miller.
Farmers may want to begin scouting their soybean fields for aphid activity.
“We’re starting to see aphid activity, and to this point it hasn’t been too big of a problem,” said Miller. “Up until a few days ago, the activity was really light and hard to even spot. Now, it’s really variable from field to field. Some are at our threshold of 250 aphids per plant, with 80 percent of the plants infested, and they need to be sprayed. But there are other fields even a few miles away that don’t need spraying.”
Soybean aphids are showing up in south central Minnesota fields, but may not be at threshold yet. It’s important to scout fields as soon as possible. (photo from sdsoybean.org)
Miller wants farmers to avoid the temptation to spray without checking fields to see if it’s necessary.
“Given the current economic situation, people could benefit from waiting to spray (if a field isn’t at threshold),” said Miller. “We’re not out of the woods. These products won’t necessarily end the infestation. There are fields that may see recolonization later on. There are a lot of aphids flying around.”
A story developing out of southwest Minnesota involves non-performance of aphid killing products.
“There’s a narrow band of area in southwest Minnesota where there’s been some non-performance of insecticides,” said Miller. “How we stay away from that is waiting to spray until we need to, and that also can limit the need for a second application. But you still need to stay on top of it. Things can change quickly, and it won’t always be evident from the road.”
He said the overall condition of the corn looks good.
“We’re in the R2 to R3 stage,” said Miller. “I was looking at doing some early harvest estimates, and it’s a little tough because we have a long way to go. However, assuming we continue with good conditions, we might be looking at anywhere from 187 to 260 bushels per acre. If we can continue with good conditions, the harvest could be a little above normal.”
So far, the corn crop doesn’t seem to be feeling a lot of pressure.
“The corn really looks good,” Miller said. “I know there was some concern in northern Iowa with corn on corn leaf blight, but the corn here looks good.
“The bottom leaves haven’t even fired up yet, which they do when they hit the R3 stage. At that stage, the plant begins to recirculate some of its nitrogen and nutrients to use things up, and that hasn’t happened yet. The soil and the environment are still providing adequate fertility.”
The small grain harvest is progressing well in south central Minnesota.
The oats harvest in south central Minnesota is all but wrapped up, according to Ryan Miller of the Extension Service. Results are generally in the 150 bushel per acre range. (photo from pond5.com)
“I’m hearing tremendous yields on oats,” he said, “somewhere in the area of 150 bushels. That’s a phenomenal yield for small grains. Haven’t heard a lot on wheat yields yet, but I think that will be good too.”
He added, “Reports out of northwest Minnesota are that they have had good yields, but the protein content was a little low.”
As warmer weather continues, the Minnesota Department of Agriculture (MDA) urges growers and applicators to use caution when spraying soybean fields to control aphids.
Soybean Aphids are pictured here on the underside of a soybean leaf (photo from channel.com)
“Because soybean aphid populations can increase rapidly, growers should scout fields regularly,” said MDA Inspection and Enforcement Manager, John Peckham. “Be prepared to treat, if necessary, but first determine if the 250-aphid per-plant threshold has been reached.”
When growers determine it is necessary to spray for aphids, there are several factors that should be considered. First, whether the pesticide is applied by the grower or a hired applicator, it’s a good idea to check for bee colonies in the area before spraying. The DriftWatch website (https://mn.driftwatch.org/map) can help applicators see where some beekeepers have voluntarily mapped colony locations. It is not comprehensive, so check your municipal directory for contact information on other local beekeepers.
Also, don’t apply insecticides when bees are foraging or present in nearby crops. Bees actively forage after sunrise and before sunset. When there are blooming weeds near an application site, bees may be present.
Second, it is crucial to read and follow all product labels. They indicate the correct amount of product to use and specify mixing, timing, and spraying directions for safe insecticide use and storage.
Some product labels for soybean aphid control have mandatory application setback restrictions for lakes, river and streams, or sensitive areas that affect humans. Mandatory setback distances can vary with application method. Check individual product labels for application restrictions.
Finally, Peckham says communication is an important aspect to a safe and prosperous growing season.
“Talk to your neighbors that have expressed concerns over spraying and give them advanced notice,” he said. “You can head off problems later on if you plan in advance and let neighbors know when an application will be made.