Issue link: https://read.dmtmag.com/i/662797
www.goodfruit.com Good Fruit Grower APRIL 15, 2016 35 A single handful of good orchard soil is teeming with about 7.5 billion microbes, including some 6 billion bacteria that are busy releasing minerals and other ele- ments essential for healthy trees. However, soil science for the past 50 years has mostly neglected this dynamic biological component. Instead, the science has taken primarily a chemical- and physi- cal-driven approach with tests designed to determine the need for various fertiliz- ers and how much to apply, said Dr. George Bird, who has spent years studying soil quality as a professor and researcher in Michigan State University's entomol- ogy department. Recent soil tests, such as those that Cornell University, Haney (U.S. Department of Agriculture's Agricultural Research Service, or USDA- ARS) and Solvita have rolled out over the past few years, have begun to report these key biological parameters, but growers have yet to embrace the new tests, and those who have are struggling to under- stand what the test results mean, he said. "Soil health is a new concept, and encompasses indicators that grape growers and tree fruit growers are often not familiar with, but it is something I feel very strongly that they'll all be using within the next decade," Bird said. Soil testing changes One of the parameters recently added to the new tests is active carbon potential. Carbon bonds to most of the minerals essential to plants and their fruits, and a soil's active carbon potential is a measure of how readily carbon releases those minerals for uptake by plants. Active carbon potentials differ from one soil to the next, and therefore can have different effects on the growth and development of plants, including vines and trees. "That means that active carbon is very important in relation to the health of orchard soil," Bird said. Another vital com- ponent of soil health is nitrogen utilization. "Soil is a very nitrogen-deficient environment, but you need nitrogen for growth and development of plants, because it's a significant compo- nent of nucleic acids, such as DNA, and proteins," he explained. That's where bacteria and other Soil gets a closer LOOK Soil tests tell growers what they need to know. by Leslie Mertz George Bird Early Season Kalibrate applied at planting time or side-dress is taken up from the soil along the length of young roots, particularly by root hairs. Potassium moves to leaves and fruit via the phloem and xylem, and is transported in all directions between plant organs in response to metabolic demand. Provide the potassium your crop needs, when it needs it, by using the most efficient potassium nutrient products on the market: Kalibrate and Sure-K. These products provide available potassium to the plant at the right times in the growth cycle – despite the drought. Learn more at agroliquid.com/Kchallenge Mid-Late Season Sure-K as a foliar application or fertigation enables the flexibility to provide available potassium, which is actively taken up by plant tissues. Sure-K enters the plant more effectively than conventional potassium fertilizers and has excellent crop safety. Once in the plant, Sure-K is rapidly transported and redistributed to areas of greatest metabolic demand. Sure-K can also be mixed with crop protection products, reducing the number of passes on the field.