Preparing for Root Diseases
With increasing costs around labor and resources, superintendents should address pathogen populations early with simple, proactive steps to ease the burden of potential curative disease measures later in the season. Most soil-borne pests begin infecting roots in cool, wet weather of spring – so starting applications soon sets the stage for effective and efficient disease management all year long.
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Early season knockdown of fungal diseases with DMI fungicides:
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All of these diseases become active in early spring (at indicated soil temperature), although symptoms may not appear until summer:
- Fairy ring 55-60°F at 2” depth
- Brown ring patch 55-60°F at 2” depth
- Take-all patch 55-60°F at 2” depth
- Summer patch 65-70°F at 2” depth
- Anthracnose 65-70°F at 2” depth
- Dollar Spot 60°F air temperature
- It is well documented that early season applications targeted for these diseases will reduce inoculum and disease pressure for extended periods by keeping fungal populations low
- Early season DMI applications like Densicor®, Bayleton®, Tartan® Stressgard® or Mirage® Stressgard will be effective against all of the important diseases listed above
- With a light watering-in after application (0.1 - 0.125”), DMIs are highly effective tools in managing damaging root and crown diseases in the spring
- Repeat applications for these diseases should be made every 28 days, regardless if the weather has cooled since your initial application
- If a root disease like summer patch is historically problematic on your course throughout the summer, continue DMI applications on 28-day intervals through August
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All of these diseases become active in early spring (at indicated soil temperature), although symptoms may not appear until summer:
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Addressing Pythium root diseases - Pythium root rot is caused by over 30 different species – many of which start infecting turf in cool, wet spring weather:
- Applications for Pythium root rot should start when 2” soil temps average 60°F for five consecutive days
- Many start with spring applications of Banol® at 2-3 oz/1000 sq ft (Banol First Program)
- Be sure to water Pythium root rot applications in with 0.1 - 0.125” of irrigation after application for optimal efficacy
- Ensuing rotational applications should include Signature® XTRA Stressgard alone or in combination with Banol for Pythium root diseases and to maximize plant health with the increases photosynthesis and stress mitigation of Stressgard
- Segway® (Ishihar Sangyo Kaisha, LTD) is also a highly effective rotational fungicide
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Don’t neglect the nematodes - plant parasitic nematodes like stunt, root knot, spiral, lance, and ring all become active and begin feeding in the spring when turfgrass root production is peaking:
- Saturated conditions that compromise root health may create further susceptibility to underlying nematode populations
- If nematode problems are confirmed, consider making an early season nematicide application along with your fungicides to protect roots and reduce nematode populations
- Indemnify® can be used to target root-infecting nematodes with a single spring application. An additional fall application can be considered if needed
- Indemnify should be applied at 0.39 fl oz/1000 sq ft (“spot-applications” as indicated on the label would encompass any and all greens on a course)
- Irrigate with 0.1 to 0.125” within 24 hours of application
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Tank-mixes to control most of the potential issues - to control all of the above pests, a couple of applications of a three-way tank-mix in mid-spring should go a long way to enhance turf performance all season:
- Densicor at 0.196 fl oz/1000 sq ft (or Mirage Stressgard at 2 oz/1000 sq ft) + Banol at 2 oz/1000 sq ft + Indemnify at 0.19 fl oz/1000 sq ft
- Target this application at 55-60oF 2” soil temps followed by watering in with 0.1 to 0.125”
- Watch for Envu’s new Resilia™ this fall that will simplify the tankmix to control most root pathogens
- Need more info – for more information, contact your Envu Area Sales Manager if you need assistance
Solution Sheet - Fairy Ring - cool season | |
Solution Sheet - Fairy Ring - warm season | |
Solution Sheet - Summer Patch - cool season | |
Solution Sheet - Brown Ring Patch - cool season |
Spring applications will go a long way to improve rooting season-long (Envu).