Plant Growth in Soil BSS6
Objectives LESSON OBJECTIVE ENABLING OBJECTIVES • Associate soil characteristics to the effect on plant growth. • Detail the soil testing process and how it relates to plant growth. • After completing this lesson on Plant Growth in Soil, students will demonstrate their ability to apply the concept in real-world situations by obtaining a minimum score of 80% on the Soil Test Interpretation Report Evaluation. 01 02
Key Terms • pH • Soil Test • Cation Exchange Capacity • Soil Sample
Soil pH • Scale that measures acidity to alkalinity • 0-14 scale • pH range of Missouri soils is about 4.5 – 8.4 • ph 7 = neutral • Neither acid nor alkaline • pH increases 10 times between consecutive units • pH 5 is 10 times more acidic than pH 6 • pH 6 is 10 times less acidic than pH 5
Importance of pH • Quick estimate of balance between the plant nutrients in the soil (K, Mg and Ca) and other non-nutrient elements (H,Al,etc.) • Indicates if agricultural lime is needed • Can affect pesticides • Can affect herbicides
Correcting pH • Acidity = Caused by leaching of bases by water or the absorption of base nutrients by growing plants • Applying lime = Raises pH • Liming helps release other non-base plant nutrients and make them more available to plants
Seventeen Essential Plant Nutrients Click to watch a video on Nutrient Deficiencies in Plants
Objective 2Detail the soil testing process and how it relates to plant growth
Soil Testing Click for videos on taking soil samples
Factors Influencing Sampling • Should be representative of a field or area within a field • Field should be divided if different soil types are present, different types of crops are grown within the field or if natural surface texture varies • Eroded and wet areas should be sampled separately
A – Field Information Information obtained from person who requested soil test used to identify the field and summarize previous management B – Soil Test Information Results of soil test performed on sample Soil salt pH Available phosphorus, potassium, calcium and magnesium Organic matter Neutralizable acidity Cation exchange capacity C – Rating Rating for salt pH and nutrients tested Indicates relative level of each nutrient tested Indicates probability of particular fertilizer to increase crop yield D – Nutrient Requirements Cropping options Yield goal Fertilizer recommendations
E – Cropping Options Cropping plans or crops in which fertilizer recommendations were requested F – Yield Goal Shows level of production selected for crops in Section E Yield goal should be based on soil type, yield history, fertility level, irrigated vs. non-irrigated land and economic considerations G – Pounds Per Acre Lists fertilizer recommendations for crops and yield goals listed H – Limestone Suggestions Gives suggested amount of limestone to raise soil saltpH to optimal level for cropping options
Conclusion It is important to understand the complex characteristics of soil so that farmers and land owners can manage the soil properly and effectively use it to grow plants. Soil quality affects plant nutrients and can lead to either gains or losses in yield, and create financial consequences for a producer.
Exit Card • What did you learn about Plant Growth in Soil? • What questions do you still have about Plant Growth in Soil?