ISSUE 5 June 2, 2005
During the past week (May 25 to 31), the south-central regionís rainfall ranged from 0.1 inches at Pillsbury to 1.2 inches at Jamestown as recorded at NDAWN (North Dakota Agricultural Weather Network) sites. The regionís soil moisture is currently adequate. While the majority of soybean, dry bean and sunflower acres have been planted, growers are struggling to complete crop planting due to recent rain and wet soils. Winter wheat is at or near the heading stage. The regionís cool-season crop and corn fields generally continue to have good to excellent plant stands. The majority of the regionís spring wheat crop is in the 4_leaf to jointing stages. The continual cool and wet weather has helped maintain excellent yield potential in small grain. POST herbicide, fungicide, and N application in wheat have been a challenge due to rain and wind. Soybean fields are slowly becoming established.
Winter and spring wheat fields in several south-central counties have low levels of leaf rust, as detected through NDSUís IPM crop scouting program. Also, tan spot is commonly found in the region. Consider an early-season (tillering stage) fungicide application to spring wheat varieties susceptible to tan spot and rust, especially if wheat is grown in small grain residue and weather conditions continue to be favorable for foliar disease. Check the following website for a wheat disease forecast in your area:
Area Extension Specialist/Cropping Systems
NDSU Carrington Research Extension Center
Many areas in southwest North Dakota received over an inch of rain this past week. In this part of the state NDAWN reported rain fall totals for the week in a range from 0.38 inches near Mandan to 1.20 inches at Dickinson. Some producers recorded up to 2.0 inches in the Belfield Ė Amidon area. For the month, Dickinson recorded 4.47 inches of precipitation and Hettinger recorded 2.20 inches of precipitation. The 108-year average for the month of May at Dickinson is 2.29 inches while the 49-year average at Hettinger is 2.62 inches. County extension agents report pastures are green and growing Ė "the greenest it has appeared in several years." With rainfall, more tan spot problems have been reported. The worst tan spot problems are found in wheat fields where the previous crop was wheat. Many producers are tank mixing a foliar applied fungicide registered for tan spot control with their herbicides. Producers are waiting for fields to dry so they may continue spraying and planting operations. Winter wheat is in the jointing to flag leaf stage. Winter rye is in the boot. Early seeded barley and spring wheat is in the six-leaf stage. Alfalfa is about 12 inches to 18 inches tall. Corn that was seeded earlier in April and May is up and growing. Some wheat, corn, most sunflowers and some of the annual forage crops still need to be planted.
Producers should examine crop development stage prior to applying post-emergent herbicide products. Winter wheat has past the point where many herbicides can be used and will soon be beyond the point where any herbicide can be used. Producers should also take time to clean out the sprayer when changing pesticide products and between crops. This past week a report was received indicating a poor job of cleaning out the sprayer. Thoroughly cleaning out the sprayer Ė more than triple rinsing Ė is required to avoid crop injury and death.
The number of growing degree units for alfalfa weevil (48oF base temperature) according to NDAWN at Beach 220, Bowman 214, Dickinson 266, Hazen, 276, Hettinger 257, Mandan 326, and Mott 233. Scouting in the Mandan area for alfalfa weevil should begin next week. Look for pinholes in new expanding leaves near the terminal of the plant. This feeding should direct scouts to investigate these plants for young larva. With alfalfa approaching bloom, harvesting to control alfalfa weevil larva is an option for effective control. However, the field should still be scouted after the hay is removed for larva. Look near the base of the stubble, particularly where the windrow laid, for larva feeding on new growth near the crown of the plant. If significant levels of alfalfa weevil larvae are found then an insecticide will be needed. Clover weevil feeding has been found on sweet clover. Diamondback moth (pest of canola) numbers have been low at the trap sites near New England and Dickinson.
The heart-shaped yellow bracts on leafy spurge are becoming noticeable indicating the plant will be flowering soon. It also indicates herbicide applications to control this weed will need to occur soon.
Area Extension Specialist/Cropping Systems
Dickinson Research Extension Center