Slide 1 LHAP 207 Turfgrass Regular Maintenance: Mowing Slide 2 Maintenance Fertilizer Mowing Watering Raised up or down depending on: Environment Plant Growth Stage Slide 3 Turfgrass Mowing: Removes parts of the foliage by: Tearing or slicing Affects the plant’s physiology: Slide 4 Turfgrass Mowing: The Effect Fluid exudes from the leaf This fluid is water and organic compounds (guttation and exudation) The plant tries to repair the wound Open wounds create entry points for pathogens Plant tries to replace lost tissue Carb usage for repair causes energy dips! Weak plants are easy pickings for pathogens Additional stresses can be enough to severely damage a plant Root growth stops while the plant fixes the wound Slide 5 Mowing: Turf Responses Continued Mowing Increases: Shoot growth and Density Tillering, Rhizome and Stolon formation Overall amount of chlorophyll Increased succulence in the shoots Continued Mowing Decreases: The overall size of the plant Shorter root systems and plant heights Slide 6 Mowing Heights Definition: Distance above the soil surface at which the turf is mowed Mowing heights of turfgrass are determined by: Natural growth habit of the turf Health and condition of the turf Purpose for which the turf is used Slide 7 Mowing Height Ranges Kentucky Bluegrass: 20-75 mm Perennial Ryegrass: 20-75 mm Creeping Red Fescue: 20-50 mm 1mm 20 mm 40 mm 60 mm 80 mm Slide 8 Mowing Height The Unbreakable Rule: Never remove more than ⅓ of the leaf tissue in one mowing What is your Home Lawn made of? Ideally it can increase in height by ⅓ and still be competitive at any stage in the mowing cycle. (50 mm / 3 = 16.7 mm. 16.7mm x 2 = 33 mm) A home lawn polystand SHOULD range between 33 - 50 mm (around 2” in height maximum) Slide 9 Mature Kentucky Blue Mowed @ 7 day intervals during peak growth Not Frequent Enough. Slide 10 Scalping Occurs when too much foliage is removed in a single mowing Uneven ground, excessive thatch, infrequent mowing intervals Grass turns brown, stubby Most of green tissue has been removed Plant chopped back to the sheath and crown Not used to exposure and dries out Slide 11 Scalping Slide 12 Mowing Quality Dull mowers: shred leaves Plants take much longer to recover Grass may discolour Puts extra strain on your engine Slide 13 Mowing Quality Good quality cuts produce: A sharp, even cut to reduce sealing and recovery period Prevention of desiccation and disease, etc. Balanced relationship between fertility and cutting quality Slide 14 Mowing Frequency Frequency can be determined using the ⅓ Rule and this question: Are there clippings produced when I mow? How often you mow? Determined by shoot growth rate, function of turf, cutting heights, environmental conditions Slide 15 Types of Mowers Slide 16 Types of Mowers Reel Scissor action of blades mounted on a cylinder and rotate against a fixed bed knife Expensive to purchase and maintain Slide 17 Reel Slide 18 Reel Slide 19 Types of Mowers Rotary Horizontal blades spinning at high speeds and the action tears off the blade of the grass Inexpensive to purchase and maintain Does not always produce a fine and clean cut Articulating mowers are useful on areas with undulations ~ Versatile Slide 20 Rotary Slide 21 Rotary Slide 22 Flail Spins a cylinder with sharpened knives that hang from a pivot Types of Mowers Slide 23 Flail Used for rough cutting Tears the grass plant Slide 24 Slide 25 Slide 26 Hover Mower / Fly Mower Robotic Mower Slide 27 SAFETY MOMENT Beware of flying debris from ejection ports!!! Slide 28 Clippings Removing clippings may: Reduce disease Reduce injury from clipping ‘piles’ Less interference with play Removal: Vs No Removal: Frequency reduces need to remove clippings Reduces fertilization requirements Clippings can be ‘mulched’ Insulation layer to moderate temperatures Increase wear tolerance Adds to humus layer & mat Slide 29 Mowing Height Summary Low Maintenance Polystand with CRF: Mowing at the high end is most realistic for Lawn Grade turf (closest to once per week) Increase your relative percentage of CRF for slower re-growth Set your mower at 1” - 1.5” (as close to 3.3 cm as possible) Check before you mow - are you over the 2” (5 cm) mark? Increase your mowing frequency if so… or evaluate the health of the turf and suggest a reduction in fertilizer and water. Mulch your clippings whenever possible.