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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Annuals and Perennials > Ornamental Grass

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Annuals and Perennials > Ornamental Grass

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  • rust 1
  • rust 2

Puccinia and uromyces sp.

  • Small yellow, orange or red raised blisters on leaves and stems
  • Powdery orange spores brush off infected leaves and can be seen on a white tissue
  • Leaf tissue around the rust spots turns yellow and sometimes brown
  • In severe cases rust spots may merge together to form large yellow or orange streaks or blotches
  • Severely infected leaves may turn brown, dry up and die
  • Rust spots become dark brown or black late summer and early fall
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  • powdery mildew 1
  • powdery mildew 2

Powdery Mildew
Blumeria graminis

  • Powdery, fluffy, white spots or blotches on leaves
  • Tiny raised black dots may be visible within white spots late summer or early fall
  • Severely infected plants may be completely covered in white or grayish white fungi
  • Common or grasses grown in shady areas
3 of 4
  • ergot 1
  • ergot 2

Claviceps purpurea

  • Random, purplish-black hard oblong rods emerging from the seed head
  • Purplish-black rod is 1 to 5 times the size of a normal seed
  • Sticky drops of fluid may be seen on seed head early in the season
  • More information on Ergot ...
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  • Animal damage 1
  • Animal damage 2
  • Animal damage 3

Deer, rabbit and other animal damage

  • All of large sections of leaves are cut off and missing, leaving only a stem or petiole (leaf stalk)
  • Animal foot prints or dropping near plant
  • Often happens suddenly, overnight
  • More information on Deer damage...

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