Crop & Pest Report

Sunflower Insects - Economic Thresholds for 2011 (7/28/11)

RED SUNFLOWER SEED WEEVIL adults will begin to emerge in late July and continues until mid-August. Adult weevils are reddish brown and ⅛ inch long.

Insecticide Timing and Mode of Action for Control of Sunflower Insect Pests (7/28/11)

This insecticide trial was conducted near Mapleton, ND in 2010. Trial was arranged in a RCBD design with 4 replications. Three different mode of actions were tested: organophosphate - OP (Lorsban), pyrethroid – P (Asana) and OP + P (Cobalt).

Why are there so many Dragonflies? (7/28/11)

Dragonflies belong to the Order Odonata and there are about 400 species in United States. There are many dragonflies flying around fields and yards this year.

Root Lodging in Corn (7/28/11)

Last week in the Crop and Pest Report, I included a short article about green-snap in corn and the yield losses associated with this phenomenon. I did not mention root lodging in that article, primarily because most of the damage that I observed was due to green-snap and there was little root lodging.

Sunflower Growth and Development (7/28/11)

In a normal year more than 50% of the sunflower acres are planted by May 29th. Based on the 2011 North Dakota Agricultural Statistics Service, 64% of the sunflower crop in ND was planted by June 12th.

Sugarbeet Crop Progress (7/28/11)

The sugarbeet crop is off to an unusually late start, one year after the earliest planting ever. Typically, all things equal, later plantings have lower yields than earlier plantings. As such, all the sugar cooperatives in our area increased their planted acreage by about 5% so that they will have enough beets to fully utilize the processing capacities of their factories.

Small Grain Diseases on the Rise (7/28/11)

NDSU IPM field scouts looked at just 43 wheat fields during the week of July 18-22, but it was clear that disease pressure had increased with the continued rains and very warm temperatures.

Correction on Downy Mildew Fungicide Resistance (7/28/11)

Last week I said that pathogen resistance to either Idol and Apronmaxx had not been identified.

Scouting for Dry Bean Rust (7/28/11)

Dry bean rust has not been reported in the region yet this year, but conditions are favorable for rust infection and development (humid, heavy dews, warm temperatures). I would encourage growers to scout for dry bean rust in the upcoming weeks.

Sidedress/Topdress Options for Corn (7/28/11)

In some of my corn N plots this season on high clay soils in the Valley, I am certain that we lost over 100 lb/acre of N. If the corn is not yet tasseled, given the price of corn right now, application of reasonable rates of N will be profitable.

Report on Recent Sulfur and Zinc Applications to Striped Corn in the Valley (7/28/11)

Last week I reported on top yellowing and striping on some corn with restricted root systems in the wet high clay soils in the Valley. A little less than a week ago I applied the equivalent of 10 lb S/acre as gypsum granules and about 10 lb Zn/acre as zinc sulfate granules to an entire N rate study between Mapleton and Casselton on high clay, very wet soils.

Dry Bean Herbicide and Dessicant Update (7/28/11)

Sharpen is a new desiccant from BASF that is expected to be registered for use on dry beans by fall in time for desiccation of this year’s dry bean crop. In NDSU trials, Sharpen has been as effective, and sometimes more effective, than Valor, which has become a standard in dry bean desiccation.