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Soil Quality Important factor in farm crop production Soils determine which plant species yields the most, the time of harvest, investments that must be made Soil quality is the most important factor in farm crop production. It largely determines what can be produced on the farm and directly affects the landowner’s economic investments on the farm. For this reason, soil quality gets a gold star for importance.

Factors Controlling Plant Growth Light Mechanical Support Heat Air Water Nutrients All except for light, involves soil The 6 factors controlling plant growth are 1) light, 2) mechanical support, 3) heat, 4) air, 5) water, and 6) nutrients. Of these six, all but one, light, is supplied by the soil. Soil provides a place for roots to grow for support. Soil temperature largely regulates plant growth. As we will see shortly, one-half of the soil is made up of air and water. Soil contains minerals and organic matter that provide essential nutrients to plants.

pH Acidity (low pH and alkalinity (basic-higher pH) Scale from 0 to 14 with 7 representing neutrality, <7 represents acidity, and >7 represents alkalinity pH has a significant impact on the availability of soil nutrients pH 6.5 is the objective for most ag crops pH: expression of both acidity and alkalinity on a scale whose values run from 0 to 14 with: 7 representing neutrality, less than 7 represents acidity and greater than 7 represents alkalinity. pH has a significant impact on the availability of plant soil nutrients. Most agricultural crops prefer a pH 6.5 for best growth.

pH Scale The figure shows the break down of where acidity to alkalinity is on the pH scale. PH 7 is neutral. The figure shows the break down of where acidity to alkalinity is on the pH scale. PH 7 is neutral.

pH Effect on Nutrient Availability This has a direct impact on plant health. For most agricultural crop recommendations, the goal is to have a 6.5 pH. At this pH most of the essential plant nutrients are available. This graphic shows how the major plant nutrients change in availability with the increase and decrease of pH. The wider the black band in this graphic, the more available the nutrient. Graphic shows how the major plant nutrients change in availability with the increase and decrease of pH. The wider the black band in this graphic, the more available the nutrient. This has a direct impact on plant health. For most agricultural crop recommendations, the goal is to have a 6.5 pH. At this pH most of the essential plant nutrients are available.

pH Preferences by Plants As can be seen from the black bands, most plants prefer a pH between 5.5 and 7.0. This graphic shows the range in pH preferred by plants. This shows that it is important for producers to know the fertility and pH requirements of the plants they plan to grow. A pH below 5.5 is considered to be very acid and above 7.0 is alkaline. Graphic shows the range in pH preferred by plants. This shows that it is important for producers to know the fertility and pH requirements of the plants they plan to grow. As can be seen from the black bands, most plants prefer a pH between 5.5 and 7.0. A pH below 5.5 is considered to be very acid and above 7.0 is alkaline. .

16 Essential Elements Primary elements = plant nutrients that are needed and most used, can be found in commercial complete fertilizers The fertilizer number reflects these three elements, i.e. 10-6-4. Primary Nitrogen (N) Phosphorus (P) Potassium (K) Secondary Sulfur (S) Magnesium (Mg) Calcium (Ca) Secondary elements = the next most needed nutrients, Magnesium and calcium are obtained from liming materials In the Industrial revolution, most came from air pollution (sulfur dioxide), now can be supplemental as pollution has decreased There are three primary elements. They are nitrogen, phosphorus, and potassium. Primary elements are those plant nutrients that are needed and most used by plants for growth. Secondary elements are the next most needed plant nutrients. These include sulfur, magnesium, and calcium. The primary nutrients can be found in commercial complete fertilizers as the fertilizer number reflects these three elements, i.e. 10-6-4. Magnesium and calcium are obtained from liming materials. During the Industrial revolution, most of our sulfur came from air pollution (sulfur dioxide). In recent years, producers have had to routinely include supplemental sulfur to their crop fertility programs as the air around us becomes less contaminated with sulfur.

16 Essential Elements (part 2) Micronutrients = nutrients needed in small amounts Micro-nutrients Iron (Fe) Manganese (Mn) Boron (B) Chlorine (Cl) Zinc (Zn) Copper (Cu) Molybdenum (Mo) Micronutrients are plant nutrients that are needed in only small amounts. These include iron, manganese, boron, chlorine, zinc, copper, and molybdenum. All 16 essential elements are important. A deficiency in any one of them will impact on plant growth.

16 Essential Elements The final three (3) essential elements to plant growth come mostly from air and water. Carbon (C) Hydrogen (H) Oxygen (O) The final three- (3) essential elements to plant growth come mostly from air and water. They are carbon, hydrogen, and oxygen. Carbon in the form of carbon dioxide (CO2) and oxygen are found in abundance in the air. Water (H2O) is a source of hydrogen and oxygen.

The Primary Elements Nitrogen: gives plants their green color, promotes above ground growth, and regulates use of other elements Phosphorus: positive effect on - cell division - stem strength - crop maturation - root development - flowering/fruiting - disease resistance Nitrogen: It gives plants their green color, promotes above ground growth, and since it stimulates plant growth, it regulates the utilization of the other 15 essential elements. Phosphorus: It has a favorable affect on: cell division, stem strength, crop maturation, root development, flowering/fruiting, and disease resistance.

The Primary Elements Potassium (K) Essential for starch formation and movement of sugars. Essential to the development of chlorophyll, helps plants to over-winter

Nutrient content of commercial fertilizers Expressed as a percent called the “guaranteed analysis” or fertilizer grade. Nutrient content always appears in this order: % total nitrogen % available phosphate (P2O5), or phosphoric acid % soluble potash (K2O) The nutrient content of commercially available fertilizer is expressed as a percent called the guaranteed analysis or fertilizer grade. This always appears as % total nitrogen, % available phosphate, or phosphoric acid, and % soluble potash.

The Fertilizer Number The fertilizer number refers to a ratio of N-P-K 5-10-5 (1-2-1 ratio) has: 5% N 10% P205 5% K20 = 20% The other 80% of the material is called the carrier. This is typically some inert material. 10 - 6 - 4 (2-1-1 ratio) 10 -10 -10 (1-1-1 ratio) The fertilizer number refers to a ratio of nitrogen to phosphorus to potassium. 5-10-5 fertilizer is an example of a 1-2-1 ratio fertilizer. The fertilizer number reflects the percentage of nutrients in the material. 5-10-5 fertilizer has a total of 20% nutrients, with the other 80% of the material being inert, or carrier material.

What does a fertilizer guarantee mean? This bag contains: 5% nitrogen--10% phosphate--15% potash or 2.5 lbs. nitrogen 5 lbs. phosphate 7.5 lbs. potash Ag-Gro-Pro 5-10-15 50 lbs. Using the analysis (grade) of the fertilizer and the total weight of the bag, the actual amount of plant nutrients in the bag can be easily calculated. For example, this 50 lb. bag of 5-10-15 contains 5% nitrogen, 10% phosphate, and 15% potash. By multiplying the nutrient percentages times the total weight in the bag, we find that the bag contains 2.5 lbs. Of nitrogen, 5 lbs. Of phosphate, and 7.5 lbs. of potash. This means that the bag contains 15 lbs. of plant nutrients and 35 lbs. of inert ingredients.

Common Fertilizers Urea 46 - 0 - 0 Ammonium nitrate 34 - 0 - 0 UAN 30 - 0 - 0 Ammonium sulfate 21 - 0 - 0 Diammonium phosphate 18 - 46 - 0 Triple superphosphate 0 - 46 - 0 Muriate of potash 0 - 0 - 60 Slide reflects a list of the most commonly used fertilizers in the region and their analyses. Many of these materials are custom mixed together to meet the specific fertility needs of a crop based on soil test results.

Crop Residue Benefits left by a previous crop or cover crop Previous crops leave little unless it was a leguminous crop Leguminous crops leave nitrogen The amount of N left depends on the species of legume and the stand density and maturity Cover crops are not harvested and will recover nutrients otherwise lost Plant fertility benefits left in the soil by a previous crop is often overlooked and not taken advantage of by producers. Leguminous crops provide the most benefit to following crops since they “fix” nitrogen and leave it in the soil for following crops to utilize. Leguminous crops can be used as crops grown for either cash, or animal feed, or as a cover crop.

A funny slide to breakup the class A funny slide to breakup the class. This could be an Iraqi surface to air missile. Don’t Overload! A funny slide to breakup the class. This could be an Iraqi surface to air missile.