Recently in the Sugar Beets Category

John A. Lamb and Daniel E. Kaiser
Soil Fertility Specialists

Nitrogen is important for corn growth. This has been a concern on growers' minds since March. First concern was with the poor tillage conditions last fall. Did the nitrogen applied stay in the soil. We attempted to answer that question in a March 18 E-news. At the time of that E-news, drought was the weather condition on everyone's mind. Now with the record rainfalls, there are concerns if nitrogen has been lost to leaching or denitrification.

Written by: Dr. Jeff Stachler, University of Minnesota and North Dakota State University and edited by Al Cattanach, Mark Bredehoeft, and Mike Metzger

Questions from sugarbeet growers have been coming in to Extension and Sugarbeet Cooperative Ag Staff about how to properly manage glyphosate-resistant waterhemp. The three Sugarbeet Cooperatives and Jeff Stachler recently met to determine the best strategy to manage glyphosate-resistant waterhemp in Roundup Ready sugarbeet.

By Daniel Kaiser
Extension Soil Fertility Specialist

U of M Nutrient Management Website

A new nutrient management website has been launched that houses most of the current fertilizer suggestions and data from the University of Minnesota. This website was made possible by funding from the Minnesota Agricultural Fertilizer Research and Education Council and was put together through a joint effort for several researchers from the University of Minnesota who's research focuses on nutrient management issues for several crops growth throughout the state of Minnesota.  We would like to thank the AFREC program because without them this effort would not have been possible

written by Dr. Jeff Stachler, Weed Scientist, UMN and NDSU

Scouting fields for weeds throughout the growing season is extremely important to maintaining herbicide effectiveness and planning for future weed control decisions. Scout fields now and at harvest to determine the effectiveness of this season's weed control practices. If weeds are present now, determine why they are present. If weeds are present due to herbicide resistance, then weed control and cropping practices must be different next season and beyond.

What is the tour about? Viewing plots for Managing glyphosate-resistant waterhemp throughout the crop rotation, especially sugarbeet and soybean.

Author: Dr. Jeff Stachler U of MN Extension and NDSU Agronomist - Sugarbeet/Weed Science

Sugarbeets have emerged or are beginning to emerge. That means it is time to begin postemergence herbicide applications to sugarbeet. Timing of the first postemergence herbicide application is the MOST critical weed management tactic, regardless of the type of sugarbeet planted.

Waterhemp is an annual weed species in the pigweed family that is capable of producing greater than 1 million seeds per plant and due to a limited number of effective herbicides, especially in sugarbeet and soybean, is difficult to control compared to most weed species.  In addition to the production of large quantities of seeds, continual germination throughout the growing season and an increased frequency of herbicide-resistant biotypes adds to the degree of difficulty in keeping this weed species under control.  The good news is that the longevity of waterhemp seeds in the seedbank is relatively short compared to most species (1 to 12% survival after 4 years), meaning complete control (zero seed production) of all plants over a three to four year time period should significantly reduce the waterhemp seed bank densities, allowing the farmer to take control of this difficult weed problem.

by Dr. Jeff Stachler, Sugar beet Weed Scientist
U of MN Extension / NDSU Extension

For those growers unable to apply glyphosate to Roundup Ready sugarbeet for the first time due to wet soil conditions, apply the maximum rate of glyphosate allowed. The maximum glyphosate rate for Roundup Ready sugarbeet is 1.125 pounds acid equivalent per acre (lbs ae/A). This equates to 32 fluid ounces per acre (fl oz/A) of Roundup-branded products, 48 fl oz/A of 3.0 pounds acid equivalent per gallon (lbs ae/gal) products, and 39 fl oz/A of 3.7 lbs ae/gal products. This glyphosate rate can only be applied up to the eight-leaf stage of sugarbeet. This rate should be applied to any field with weeds greater than two to three inches in height or with difficult to control species such as wild buckwheat, lambsquarters, and common and giant ragweed.

Temperatures over the last month have fluctuated greatly. Cold temperatures two weeks ago caused a reduction in glyphosate activity. Individual plants of lambsquarters and annual smartweed species where not completely controlled at a research location while other plants and other species were completely controlled. Cold weather in early June of 2008 also caused a reduction in glyphosate activity. The cold weather last week and early this week will likely cause glyphosate applications to be less effective until warmer temperatures persist.