Slide 1: Welcome to today s From the Dirt Up presentation, where I ll be talking to you about the importance of soil testing and maintaining healthy soils. 1
Slide 2: The first place we ll start is in defining soil. Soil is a complex mixture of minerals, water, air, organic matter, and countless organisms that are the decaying remains of once living things. Soil forms at the surface of land and is sometimes called the skin of the earth. The most important characteristic of soil is that it is capable of supporting plant life and is vital to life on earth. Steve Yergeau, Rutgers Cooperative Extension of Ocean & Atlantic Counties 2
Slide 3: There is more to soil than the broken down minerals (sands, silts, and clays) that are familiar to us all. Soil also contains about ¼ water and ¼ air, and small amount of organic matter that provides the nutrients needed for plants to grow. US Department of Agriculture/Natural Resources Conservation Service (https://www.nrcs.usda.gov) 3
Slide 4: Now that we know what soil is, we can look at how it is created/formed in the first place. The decomposition of animals and plants provides the organic materials and nutrients to the soil. Rocks and minerals get broken down through erosion and weathering (a process of freezing then thawing, which gets repeated) to make up the sands, silts, and clays in the soil. As these processes continue they build up layers over time. The picture on this slide shows those layers. Keep in mind that the creation of soil is a long and slow process. Megapixl (https://www.megapixl.com) 4
Slide 5: To determine the actual composition of what s in your particular soil, you will need to conduct a soil test. There are three main reasons to perform a soil test: the first is to maintain proper soil fertility; the second is to help guide your plant selection (either landscaping plants or vegetables); and third, to diagnose any plant problems you may have. Steve Yergeau, Rutgers Cooperative Extension of Ocean & Atlantic Counties 5
Slide 6: Healthy plants need certain levels of soil nutrients to thrive. Soil nutrients and fertility may fluctuate during the growing season. As plants grow, flower, and develop seeds and fruits, they will need higher amount of nutrients. During the fall and winter, the dormant plants require less nutrients. Large quantities of plant nutrients are removed from soils as a result of plant growth and development, and the harvesting of crops. Soil tests take the guesswork out of fertilization and are very cost effective; they eliminate wasteful spending on fertilizer products. Test results and recommendations help protect our environment by discouraging the overapplication of plant nutrients. Excess nutrients not used by plants may escape into groundwater, streams and lakes where they can contribute to environmental problems, such as algal blooms. 6
Slide 7: One way to look at what elements or nutrients must be provided for healthy plant growth is to look at plant composition. This slide and the next indicate the elements that are contained in all higher plants. Carbon, hydrogen, and nitrogen make up the bulk of the plant as water and various carbohydrates. These and the rest of the elements on this slide are called macronutrients because they are needed in relatively large amounts. 7
Slide 8: On the other hand, iron, manganese, chlorine, zinc, nickel and other metals make up lesser amounts of a plant. The rest of the elements on this slide are called micronutrients because they are needed in relatively small amounts. 8
Slide 9: One factor that helps determine the growth of plants is how acidic the soil is; which is measure by determining the soil s ph. Some plants will grow in a wide range of soil ph levels, while others require a narrow range of ph. Knowing a soil s ph will help you select plants that will thrive in the acidic or alkaline soil. Most turf grasses, flowers, ornamental shrubs, vegetables and fruits grow best in slightly acid soils which represent a ph of 6.1 to 6.9. A soil test will determine whether the soil is acidic or alkaline. It is the most cost effective way to match the ph requirements of plants that you select with the ph of the soil in which you are planting. 9
Slide 10: The ph scale ranges from 0, which is very acidic, to 14 which is very alkaline (or basic). Some examples of acidic and alkaline materials are shown on the ph scale. Pure water is considered neutral with a ph of 7. Unknown 10
Slide 11: The availability of some plant nutrients is greatly affected by soil ph. The ideal soil ph is close to neutral, and neutral soils are considered to fall within a range from a slightly acidic ph of 6.5 to slightly alkaline ph of 7.5. It has been determined that most plant nutrients are optimally available to plants within this 6.5 to 7.5 ph range, plus this range of ph is generally very good for plant root growth. In some situations, materials are recommend as soil amendments to adjust the ph. This is most commonly done for acidic soils to raise the ph from 4.5 to 5.5 up to 6.5 or approaching neutrality. This is done by applying and incorporating a liming material, often finely ground limestone that is spread using special spreaders. AgroBest (http://www.agrobest.com.au/) 11
Slide 12: Soil tests are an important tool for learning why plants lack vigor or are showing symptoms of other plant health issues or problems. For example, if trees are exhibiting yellowing (chlorotic) leaves or needles during the growing season, a soil test may reveal whether the symptom is caused by a lack of an essential nutrient, a problem with the soil ph or both! 12
Slide 13: Sometimes an unhealthy plant is suffering from a nutrient deficiency or even too much of any one nutrient. Plant nutrient deficiencies often manifest as foliage discoloration or distortion. The following chart outlines some possible problems. Grow Real Food (http://www.growrealfood.com) 13
Slide 14: The Rutgers University Soil Testing Laboratory has a wealth of information for soil testing; from how to collect a soil sample to interpreting the results of your test for your yard. The website for the Soil Testing Laboratory is: https://njaes.rutgers.edu/soil testing lab/. 14
Slide 15: Future problems can be avoided by performing a soil test. The importance of using a soil test for planning purposes cannot be overstated! Google Images (https://images.google.com/) 15
Slide 16: Thank you for your time and I ll take any questions you may have. Steve Yergeau, Rutgers Cooperative Extension of Ocean & Atlantic Counties 16