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Nutrient Budgets Make Bigger Cash Budgets

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Nutrient Budgets Make Bigger Cash Budgets THIS ARTICLE IS ABOUT… Nutrient Budgets Make Bigger Cash Budgets Highlights Just as you wouldn’t begin an operating year without a • Many services can perform financial budget, it’s just as important that you establish the soil and tissue testing while you’re in the field, so a nutrient budget. Nutrient budgets offer insight into the you can test, apply nutrients and prepare the soil without balance between crop inputs and outputs. In short, they any time lags. compare nutrients you apply to the soil to nutrients taken up • Nutrient budgets help you understand the balance by crops. This article describes what nutrient budgets are, between crop inputs and outputs. how they work on the farm and how to implement them. • Replacing soil nutrients on farms should be standard Nutrient Budgets SOP for over-fertilizing because our soil tests operating procedure One Grower showed we needed it. Our yields because we only get one shot at a crop every year. Ron Hansen grows corn and hit a plateau and wouldn’t break Test it. Balance it. Apply it! soybeans near Kankakee, IL. He’s above it. We started balancing also a strong advocate for soil nutrients and our yields went up. It testing and nutrient budgeting. was more efficient, environmentally He uses a three- to four-year soil- friendly and the hybrids responded testing program depending on better.” He says not replacing soils, combined with a tissue-testing nutrients is similar to building a house program at sidedress for fields that on a poor foundation. “No matter are strip-tilled with fall anhydrous. how much money you put in the top part of the house, it’s subject He says soil testing has advanced to premature decay because of over the years with more-site specific that poor foundation,” he says. equipment and regularly scheduled “Balanced base elements are the testing helps show relatively in your foundation for plants to maximize tests over time. Many services can yield.” perform the soil and tissue testing while you’re in the field, so you can Balanced Nutrients, Balanced test, apply nutrients and prepare the Production soil without any time lags. As the world population grows, so does its need for more food, “The primary advantage to a feed, fiber and energy. This means balanced soil nutrient program farmers must make greater and is more dollars in your pocket,” more efficient use of mineral and Hansen says. “Years ago we were organic nutrient sources. Locally • Yield history: by examining the and worldwide, farmers today are historical yields of crops take from expected to grow crops in well- specific fields, you can calculate managed and sustainable systems nutrient removal over time. Yield by neighbors, legislators, consumers history may also help better predict and raw-material buyers. the amount of uptake that will occur with similar crops planted in Contact Information: Hansen is quick to point out that the future. The Fertilizer Institute best management practices Testing for N: a good estimate of 425 Third St., S.W., Ste. 950 (BMPs) help you do just that. One Washington, DC 20024 established numbers for testing for 202-962-0490 critical component of BMPs is the soil N, especially in the Great Plains www.tfi.org nutrient budget. Nutrient budgets and western states, will give you a help you understand the balance The information presented basis to predict what will happen here is mostly general and between crop inputs and outputs. in terms of N carryover into the next conceptual. For more specific information regarding safe Inputs include fertilizers, nitrogen season. (N) fixation by legumes and applied rates of in-furrow fertilization for • Previous applications: knowing specific crops and conditions, manure, phosphorous (P) and one should refer to university what’s been applied to the field potassium (K). Outputs, or crop extension resources, and/or in years past will offer insight consult a knowledgeable and nutrient removal, take the form of into what may already be in the experienced crop advisor or grains, oilseeds, fruits, vegetables, industry professional. Also, an ground or what nutrients may no fiber, hay and forage that are Excel decision support tool is longer be present. available online. Visit the IPNI harvested. Additional outputs website www.ipni.net/toolbox. include erosion loss, leaching, • Water: consider what kind of water volatilization and nitrate reduction. has been applied to the field. Does Source Material irrigation water contain dissolved Better Crops, 2002, page 20, nutrients such as N, S or Cl? If so, it Nutrient Budgets in North What a Nutrient Budget Includes America by P. Fixen & A. Johnston should be counted as input. A nutrient budget isn’t as exact as a The Fertilizer Institute, www.tfi.org • What’s around you: consider water financial statement. An assortment International Plant Nutrition of variables affects each tract of sources that could run into your Institute, www.ipni.net land. For example, parcels near field. Is there a CAFO nearby? CAFOs may have had too much A manufacturing facility? What manure applied over time or it may makes up these water sources can have been unevenly distributed. impact how you plant. Previous flooding could throw things off, too. It’s normal to incorporate Once you’ve gathered this limits and assumptions when information, you can these use the compiling your budget. average nutrient removal rates show in Tables 1 and 2 or work with A nutrient budget includes: your Extension agent, area crop protectant or seed representative to Soil test: this component is determine even more specific rates complementary to the budget for your crops and conditions. and lets you know what nutrients are already available to crops and As Hansen says, “Replacing soil helps you plan input purchases. It is nutrients on farms should be a critical BMP in the 4R strategy. standard operating procedure, because we only get one shot at a crop every year. Test it. Balance it. Apply it!”.
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