TURF NEWS
By Tom Samples, Ph.D.; John Sorochan, Ph.D.; Jim Brosnan, Ph.D.; and Brandon Horvath, Ph.D.; Plant Sciences Department, The University of Tennessee
The Smell of Freshly Cut Turf May Help Relieve Stress fter seven years of study, researchers at the University of Queensland in Brisbane, Australia, suggest that chemicals released as turf is mowed can help people relax. Dr. Nick Lavidis, a neuroscientist, and professor Rosemary Einstein, a pharmacologist, have developed a perfume named Serenascent with the aroma of freshly cut turf. Serenascent, which combines three chemicals released when green leaves are cut, is intended to be used as a spray on bed linens, a handkerchief or clothing. Apparently, the smell of cut grass affects two parts of the brain, one related to memory (hippocampus) and the other, emotion (amygdala). These two regions of the brain are linked to the fight or flight response and to the endocrine system, which is involved with the release of stress hormones including corticosteroides. According to Dr. Lavidis, there are two types of stress. Acute stress, often considered beneficial, occurs before a task that must be done well. Chronic stress is associated with a weakened immune system and high blood pressure. Chronic stress can damage the hippocampus of the brain, reducing the number of communicating cells and leading to memory loss. Project researchers noted that animals exposed to Serenascent had little, if any damage to the hippocampus. The production of Serenascent for retail sale began in September 2009. In the future, the researchers intend to evaluate the potential for adding this beneficial, “feel-good chemistry” into other products.
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A Lawn Mowing Poll ccording to a recent poll of 3,000 people conducted in England, the average British homeowner pushes a lawnmower more than 220 miles in a lifetime. Poll results indicate that, on average, men mow 5 times a month during spring and summer, covering a total distance of 765 meters, or almost onehalf mile each time the lawn is mown. This represents a distance of
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TENNESSEE TURFGRASS
3.8 miles of mowing between March and October and 220.56 miles over the average adult lifetime (~58 years). Interestingly, women won’t travel quite this far while cutting the grass (just 47.9 miles). According to the study, men mow the lawn in more than three-quarters of English households. Forty percent of the men surveyed reported that they considered lawn mowing to be their job. Fifty-six percent indicated they found mowing the lawn therapeutic, and more than a third admitted they cut the grass the same way every time.
Tree Leaves and Dandelion Control isposal of yard waste in U.S. landfills has stopped since the Solid Waste Management Act became effective in March 1995. At the same time, the Clean Air Act of 1970 became more stringent, with the “open” burning of leaves in cities with populations of more than 7,500 also prohibited. As a result, new strategies have evolved to manage tree leaves in the landscape. As a follow-up to an earlier investigation indicating that leaf litter from deciduous trees can be used as mulch in established Kentucky bluegrass turf without adversely affecting turfgrass quality, researchers at Michigan State University report that some tree leaf mulch has herbicidal properties. Dandelion control among leaf mulches varied according to tree species. Leaf mulch with a fine (~0.5 in.) or coarse (~1.5 in.) particle size from red oak and red, silver and sugar maples was broadcast over existing Kentucky bluegrass turf at rates up to about 0.3 lb. per ft2. Regardless of tree species, a rate of about 300 lbs. of leaf mulch per 1,000 ft2 provided the greatest dandelion control (about 80% in the first year of the trial and 70% control in the second year). Sugar maple mulch consistently provided the greatest dandelion control (up to 81%). The researchers suggest that, if a natural product containing maple leaf litter can be processed so that the control of several broadleaf weeds species approaches 100%, it may have potential use in the turfgrass industry.
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DECEMBER/JANUARY 2010 Email TTA at: tnturfgrassassn@aol.com