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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Evergreen Trees and Shrubs > Juniper > Unusual growths on branches

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Juniper > Trunk/Branches > Unusual growths on branches

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  • Image: Cedar-apple rust 1
  • Image: Cedar-apple rust 2
  • Image: Cedar-apple rust 3

Cedar-apple rust
Gymnosporangium juniperi-virginiana

  • Brown 1/4 to 1 inch round woody galls on twigs
  • Bright orange, long tentacle like fungal structures emerge from galls in wet spring weather
  • Needles and twigs beyond galls may die on branches with many galls or on Rocky Mountain juniper
  • More information on Cedar-Apple Rust
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  • Image: Hawthorn rust 1
  • Image: Hawthorn rust 2

Hawthorn rust
Gymnosporangium globosum

  • Brown round woody galls up to ½ inch long on twigs
  • Thick wide orange spikes form on galls in wet spring weather, making the galls look star like
  • Rarely causes twig dieback in juniper
  • More information on Hawthorn rust
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  • Image: Quince rust 1
  • Image: Quince rust 2
  • Image: Quince rust 3

Quince rust
Gymnosporangium clavipes

  • Swollen oblong areas form on infected twigs and branches
  • Bark become flaky in older branches
  • Orange, gelatinous jelly projects from flaky, swollen bark in wet spring weather
  • Jelly dries to show an orange crust on infected branches
  • Foliage yellows and thins in severe infections; particularly on Eastern red cedar
  • More information on Quince Rust
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  • Image: Juniper broom rust 1
  • Image: Juniper broom rust 2
  • Image: Juniper broom rust 3

Juniper broom rust
Gymnosporangium nidus-avis

  • Rounded clumps of foliage can be seen throughout the tree canopy
  • These clumps are witches brooms, or clusters of many small branches
  • Swollen elongate areas with rough cracked bark can be seen on infected branches without witches brooms
  • Orange jelly forms on needles and from cracks in infected bark during wet spring weather
  • Common on Rocky Mountain juniper, eastern red cedar and prostrate juniper
  • More information on Juniper broom rust

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