WEATHER
Again , right plant , right place is imperative for turf and ornamental success . Photos by John Fech , UNL courses alike . When extremes in temperature , moisture and wind allow for it , these turfgrass varieties thrive ; when they don ’ t , they suffer or die outright . Ornamental shrubs such as camelia and Japanese holly are affected similarly .
In a classic sense , extremes — or the tolerance thereof — center around the preferred ranges for the healthy growth of turf and ornamentals and the degree of deviation from those influences ( precipitation , temperature and wind ). For the sports field manager , the bottom line is the comfort level that a person has with risking the loss of the plants due to unforeseen extremes in weather .
In addition to diseases and insect issues , extremes in weather can expand or minimize weed germination windows , especially with higher-than-average moisture and temperature . Dry and cool soils tend not to encourage germination and establishment of summer annuals , whereas warm and moist soils offer great conditions for their development . The consequence of greater weed pressure is the need for more intense management or intervention such as a second or third preemergence application for lateseason summer annuals such as goosegrass or spurge in addition to foxtail and crabgrass and additional postemergence spot spraying to control broadleaves .
Weather extremes also pose the quandary of secondary vs . primary irrigation — the consideration of sprinkler systems being relied on as the sole source of moisture for plants during times when natural rainfall doesn ’ t fall . During periods of three to four weeks of little to no precipitation from Mother Nature , the flaws in sprinklers show up ; problems such as lack of head to head coverage , hot spots where very little water is delivered , inadequate pressure , bent risers , tree roots squeezing main lines and laterals , shrubs that have grown to be in the way of the water pattern , leaking valves , risers that don ’ t rise above the height of cut and so on . When it starts raining again , these problems are still there , they are just masked .
The primary cultural practice of turf aeration is also influenced during weather extremes . When temperatures and winds are on the high side , the concern is that soil moisture will be depleted too quickly after aeration , causing desiccation . On the low side , there is greater reliance on the aforementioned flawed sprinkler system to create conducive conditions to adequately pull cores and punch holes .
An additional main issue with both herbaceous and woody ornamental plants is the long-term nature of damage from weather extremes . Though commonly overlooked , severe drought usually has a two- to three-year sportsfieldmanagementonline . com November 2023 | SportsField Management
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