Using yield/harvest data to determine if a fertility program is successful is a tricky business. Answers aren’t always apparent. A yield map, while a useful tool, can’t talk. Interpretation of why a certain area yielded the way it did and what to do about it remains firmly in the hands of the grower. And because some nutrients take time to break down and become plant available, it is often difficult to find direct correlations between yield and nutrition. Fortunately, retailers can learn much from yield data to aid them in assessing the effectiveness of a grower’s fertility program and making recommendations for next season.
Targeting Problem Areas For Improved Fertility
Harvest data serves as a season-end progress report that guides future management decisions. Yield maps identify potential areas that retailers may need to target for improvement in their recommendations.
“When we analyze yield data over a four-year period, or better yet, over an eight-year period, especially on fields with good soil sampling programs and where we have made recommendations, we see yields becoming more consistent over time,” says Troy Walker, GIS team leader at Ceres Solutions, LLP. “Yield maps allow us to find and address low-fertility areas by bringing them to optimal nutrition levels. Over time we can begin to eliminate inadequate fertility as one of the limiting factors to yield.”
Replacing Nutrients After Harvest
“It is important to replace nutrients that were lost to harvest to maintain good fertility levels in the soil,” says Walker. “Our growers are often surprised by the amount of nutrients that leave the field with the crop, particularly for potassium.”
Walker says his company has started to include yield data with their soil recommendations in an effort to help their growers account for nutrient removal in their fields. Harvest data has helped improve the accuracy of the calculations.
Fine-tuning Management Decisions
“The best use of yield data is for making management decisions,” says Walker. “What it breaks down to is how we can better manage smaller units in the field rather than taking a generalized approach like we have done in the past. Different conditions warrant different approaches, whether it is for fertilizer treatments or planting seed.” As growers and retailers use harvest data more effectively to tweak and perfect their management decisions and recommendations, the possibilities for improved yields are only going to get better.
Is Your Yield Data Accurate?
The yield data you collect is only useful if it is accurate. Follow these tips to make sure your data is as precise as possible.
Calibration: Calibrate yield monitors for each type of crop being harvested. If there is a change during the season, it pays to recalibrate for greater accuracy.
Data Collection and Storage: Save yourself the heartache of data loss, download yield data daily. This also helps ensure your monitor is running properly.
Combine Operation: Keep your speed consistent. Sudden starts and stops and frequent changes in speed can cause irregularities in data collection.
Maintenance: Check your sensors periodically and make sure they are free of dirt and plant debris.
About The Series
The fertility program is at the heart of a comprehensive cropping plan, and at the center of influence in the relationship between ag retailers and grower-customers.
To highlight the important aspects of fertilizer management programs, CropLife® magazine and sponsor PotashCorp are pleased to present the Seven Keys to Delivering Effective Fertility Programs.