Northwood Laboratory
804 Hwy 15 West
P.O. Box 510
Northwood, ND 58267
Phone: 701-587-6010
Fax: 701-587-6013
Benson Laboratory
902 13th Street North
P.O. Box 187
Benson, MN 56215
Phone: 320-843-4109
Fax: 320-843-2074
Canada Shipping Address
380 Kimberly Road
Winkler, MB R6W 0H7
Phone: 701-587-6010
Troubleshooting Problems with Plant Analysis
/in Nitrogen, Sulfur, Troubleshooting/by John BrekerA green growing crop is a delightful sight, and it is used by many people as an indicator of crop nutrient status. If you have fields with some yellow areas or slow growth, these symptoms may indicate a nutrient deficiency. Most commonly, yellow-looking plants may be deficient in nitrogen, sulfur, or both. If detected early, […]
Early Summer Grid Soil Sampling
/in Precision Ag/by Brent JaenischThe interest in early summer topsoil grid sampling (1.0- to 2.5-acres per grid) continues to increase, especially in traditional corn-soybean growing areas. In Minnesota alone, 30-40% of all grid soil samples are now collected in the summer months. The early summer period (late May to late June) is an excellent period of time to collect […]
Protecting Spring-Applied Nitrogen Fertilizer from Ammonia Volatilization
/in Fertilizer Placement, Nitrogen/by John BrekerAs the spring planting season gets underway, agronomists and farmers are asking about the best ways to protect spring-applied nitrogen. How much nitrogen might I lose if I cannot incorporate it? Does vertical tillage incorporate fertilizer enough? We have compiled some resources to help answer those questions. There are three ways to lose nitrogen fertilizer: […]
Switching More Acres to Soybean?
/in Disease, Iron, Phosphorus, Potassium, Soybean/by John BrekerThe spike in nitrogen fertilizer prices over the past month has prompted many growers to think about switching more acres to soybean in 2026. The high nitrogen fertilizer prices are squeezing the potential profitability of any crop requiring nitrogen fertilizer, such as corn, dry bean, canola, or wheat. The symbiotic nitrogen fixing behavior of soybean […]
USDA-NRCS CEMA 216: A Cost-sharing Program for Soil Health Testing
/in Soil Biological Analysis, Soil Health, Soil Physical Analysis/by John BrekerSoil health assessment includes more than traditional soil fertility analysis. Soil health encompasses physical, chemical, and biological soil properties, which all come together to provide a healthy, living soil for optimal plant growth. Traditional soil fertility analysis, supported with university research, is still the approved practice for assessing plant nutrient requirements and determining fertilizer rates. […]
Phosphorus Fertilizer Forms: Orthophosphate or Polyphosphate (Ortho-P or Poly-P)
/in Phosphorus, Starter Fertilizer/by John BrekerThis article originally appeared in the AGVISE Laboratories Spring 2024 Newsletter. Each spring, we get questions about what form of phosphate fertilizer is better. The debate over orthophosphate and polyphosphate has raged for decades. Just when we think we have put the issue to bed, it comes up again! These questions originate from the simple […]
Fall-applied Nitrogen Fertilizer: A Couple Simple Rules
/in Fertilizer Placement, Nitrogen/by John BrekerThis article is shared annually to help answer frequently asked questions about nitrogen fertilizer applications and nitrogen losses in the fall. October is here, and many people are preparing for fall nitrogen fertilizer applications. Before you hit the field, we want to share these important reminders about fall nitrogen application timing and placement to help […]
Sodic Soil Problems? Try the NDSU Gypsum Requirement Calculator
/in Saline and Sodic Soil, Soil Amendment/by John BrekerThis article originally appeared in the AGVISE Laboratories Spring 2025 Newsletter. Salinity and sodicity are two related but distinct terms to describe salt-affected soils. Salinity is the overall abundance of soluble salts, which compete with plant water uptake and reduce crop productivity. Salinity is measured as soluble salts (mmhos/cm or dS/m) on soil test reports. […]
AGVISE Demonstration Project: Lowering Soil pH with Elemental Sulfur
/in Research, Soil Amendment, Soil pH, Sulfur/by John BrekerThis article originally appeared in the AGVISE Laboratories Spring 2025 Newsletter. There may not be silly questions, but there are silly answers. Every so often, we get questions about unusual solutions to manage calcareous soils in the northern Great Plains and Canadian Prairies. The most frequent oddball “solutions” involve lowering soil pH with elemental sulfur […]
Start Strong, Finish Strong with Starter Phosphorus
/in Corn, Phosphorus, Starter Fertilizer/by Brent JaenischThis article originally appeared in the AGVISE Laboratories Spring 2025 Newsletter. Cool and wet soil conditions can limit root growth and phosphorus uptake during the early growing growing season. This is why starter phosphorus placed with or near the seed can be so effective in enhancing early plant growth and development. In small grains, starter […]
Soil Sensors: Helpful Gadgets or Hapless Gimmicks?
/in Equipment, Soil Chemical Analysis/by John BrekerThis article originally appeared in the AGVISE Laboratories Winter 2024 Newsletter. A number of new handheld sensors have hit the market, claiming to accurately and precisely measure soil nutrient content in the field, similar to traditional wet chemistry analysis at a soil testing laboratory. The draw for any person soil sampling is the ability to […]
Sticky Wet Soils? Try Adding a WD-40 Holster
/in Equipment/by John BrekerThis article originally appeared in the AGVISE Laboratories Fall 2024 Newsletter. Do you have challenges collecting good quality soil cores in sticky wet soils? You are not the only one! WD-40 has been the soil probe lubricant of choice for over 30 years to help obtain better quality soil samples. University researchers have also tested […]
Soybean Cyst Nematode (SCN) Egg Numbers Continue to Increase
/in Disease, Regional Data, Soybean/by Brent JaenischThis article originally appeared in the AGVISE Laboratories Spring 2024 Newsletter. Over the winter months, we received a lot of questions about the increasing soybean cyst nematode (SCN) egg count trends across the region. Soybean cyst nematode is the most damaging soybean pest in the United States, and the problem is becoming worse. The AGVISE […]
Zone Soil Sampling: How Many Zones?
/in Precision Ag, Regional Data/by John BrekerZone soil sampling has become a standard practice in precision nutrient management, but the grand question remains – How many zones should you be soil sampling? Well, it depends! It just makes sense that a field with more variability requires more zones than a field with little variability. Zone soil sampling separates parts of fields […]
Winter Soil Sampling: You Need the Right Tools
/in Equipment/by John BrekerSnowfall in late October and November slowed harvest and soil sampling across the region. This means some fields will be soil sampled in December and maybe January as harvest for late-season crops continues in the snow. The right equipment is the key to any project, and winter soil sampling is no different. AGVISE heavy-duty (HD) […]