Invasive Shot Hole Borers
Invasive Shot Hole Borers
Invasive Shot Hole Borers
University of California
Invasive Shot Hole Borers

Host Species

Reproductive hosts are tree species that are capable of 1) supporting beetle reproduction and 2) growing the fungi that cause Fusarium Dieback. The species below have been confirmed by UC Cooperative Extension Plant Pathologist Dr. Akif Eskalen. As research continues, these lists may change. Check back for the most recent updates.

Source: Eskalen, A. (January 2018). Eskalen Lab: Fusarium Dieback/PSHB and KSHB [List]. Retrieved from

Canker associated trees are those that only become reproductive hosts when they are previously infested with canker. When trees are healthy, the beetles cannot successfully reproduce in them. However, if the tree has a canker infested branch, the beetles can successfully colonize the tissue next to the canker. If you have tree species that are listed as "canker associated," you should monitor them and check for cankered branches. Prompt removal of these branches may help to avoid getting them infested with ISHB.

Source: Eskalen, A. & Nabua-Berhman, B. (July 2018) Personal communication.


* Indicates species native to California

** Indicates canker associated


Reproductive Host Species for PSHB

Click on a species name for symptom photos and other resources.

  1. Box elder (Acer negundo)*
  2. Big leaf maple (Acer macrophyllum)*
  3. Evergreen maple (Acer paxii)
  4. Trident maple (Acer buergerianum)
  5. Japanese maple (Acer palmatum)
  6. Castor bean (Ricinus communis)
  7. California sycamore (Platanus racemosa)*
  8. Mexican sycamore (Platanus mexicana)
  9. Red willow (Salix laevigata)*
  10. Arroyo willow (Salix lasiolepis)* 
  11. Avocado (Persea americana)
  12. Mimosa/Silk tree (Albizia julibrissin)
  13. English oak (Quercus robur)
  14. Coast live oak (Quercus agrifolia)*
  15. London plane (Platanus x acerifolia)
  16. Fremont cottonwood (Populus fremontii)*
  17. Black cottonwood (Populus trichocarpa)*
  18. White alder (Alnus rhombifolia)*
  19. Titoki (Alectryon excelsus)
  20. Engelmann oak (Quercus engelmannii)*
  21. Cork oak (Quercus suber)
  22. Valley oak (Quercus lobata)*
  23. Coral tree (Erythrina coralloides)**
  24. Blue palo verde (Cercidium floridum)*
  25. Palo verde (Parkinsonia aculeata)*
  26. Moreton Bay chestnut (Castanospermum australe)
  27. Brea (Cercidium sonorae)
  28. Mesquite (Prosopis articulata)*
  29. Weeping willow (Salix babylonica)
  30. Chinese holly (Ilex cornuta)
  31. Camellia (Camellia semiserrata)
  32. Acacia (Acacia spp.)
  33. Japanese wisteria (Wisteria floribunda)
  34. Goodding's black willow (Salix gooddingii)*
  35. Tree of heaven (Ailanthus altissima)
  36. Kurrajong (Brachychiton populneus)
  37. Black mission fig (Ficus carica)**
  38. Japanese beech (Fagus crenata)
  39. Dense logwood/Shiny xylosma (Xylosma congestum)
  40. Mulefat (Baccharis salicifolia)*
  41. Black poplar (Populus nigra)*
  42. Carrotwood (Cupaniopsis anacardioides)
  43. California buckeye (Aesculus californica)*
  44. Canyon live oak (Quercus chrysolepis)*
  45. Kentia Palm (Howea forsteriana)
  46. King palm (Archontophoenix cunninghamiana)
  47. Tamarix (Tamarix ramosissima)
  48. Red flowering gum (Eucalyptus ficifolia)**
  49. Liquidambar/American sweetgum (Liquidambar styraciflua)**
  50. Honey locust (Gleditsia triacanthos)
  51. Brazilian coral tree (Erythrina falcata)**
  52. Purple orchid tree (Bauhinia variegata)**
  53. Council tree (Ficus altissima)**
  54. Tulip wood (Harpulia pendula)
  55. Chinese flame tree (Koelreuteria bipinnata)**
  56. Laurel-leaf snailseed tree (Cocculus laurifolius)**
  57. Southern magnolia (Magnolia grandiflora)**
  58. Jacaranda (Jacaranda mimosifolia)**
  59. Coast coral tree (Erythrina caffra)**
  60. Australian blackwood (Acacia melanoxylon)**
  61. Sweet bay (Magnolia virginiana)**
  62. African tulip tree (Spathodea campanulata)**
  63. Strawberry snowball tree (Dombeye cacuminum)**

  64. Chinese wingnut (Pterocarya stenoptera)**

Reproductive Host Species for KSHB

Click on a species name for symptom photos and other resources.  

  1. Avocado (Persea americana)
  2. California sycamore (Platanus racemosa)*
  3. Coast live oak (Quercus agrifolia)*
  4. Cork oak (Quercus suber)
  5. Draft coral tree (Erythrina humeana)
  6. Black poplar (Populus nigra)*
  7. Black locust (Robinia pseudoacacia)
  8. Red willow (Salix laevigata)*
  9. Arroyo willow (Salix lasiolepis)*
  10. Fremont cottonwood (Populus fremontii)*
  11. Mimosa/Silk tree (Albizia julibrissin)
  12. Castor bean (Ricinus communis)
  13. Black Willow (Salix nigra)*
  14. Strawberry Snowball Tree (Dombeye cacuminum)
  15. Mulefat (Baccharis salicifolia)*

Reproductive Host Species for PSHB (alphabetical by scientific name)

 Click on a species name for symptom photos and other resources.

  1. Australian blackwood (Acacia melanoxylon)**
  2. Acacia (Acacia spp.)
  3. Trident maple (Acer buergerianum)
  4. Big leaf maple (Acer macrophyllum)*
  5. Box elder (Acer negundo)*
  6. Japanese maple (Acer palmatum)
  7. Evergreen maple (Acer paxii)
  8. California buckeye (Aesculus californica)*
  9. Tree of heaven (Ailanthus altissima)
  10. Mimosa/Silk tree (Albizia julibrissin)
  11. Titoki (Alectryon excelsus)
  12. White alder (Alnus rhombifolia)*
  13. King palm (Archontophoenix cunninghamiana)
  14. Mulefat (Baccharis salicifolia)*
  15. Purple orchid tree (Bauhinia variegata)**
  16. Kurrajong (Brachychiton populneus)
  17. Camellia (Camellia semiserrata)
  18. Moreton Bay chestnut (Castanospermum australe)
  19. Blue palo verde (Cercidium floridum)*
  20. Brea (Cercidium sonorae)
  21. Laurel-leaf snailseed tree (Cocculus laurifolius)**
  22. Carrotwood (Cupaniopsis anacardioides)
  23. Strawberry snowball tree (Dombeye cacuminum)**
  24. Coast coral tree (Erythrina caffra)**
  25. Coral tree (Erythrina coralloides)**
  26. Brazilian coral tree (Erythrina falcata)**
  27. Red flowering gum (Eucalyptus ficifolia)**
  28. Japanese beech (Fagus crenata)
  29. Council tree (Ficus altissima)**
  30. Black mission fig (Ficus carica)**
  31. Honey locust (Gleditsia triacanthos)
  32. Tulip wood (Harpulia pendula)
  33. Kentia Palm (Howea forsteriana)
  34. Chinese holly (Ilex cornuta)
  35. Jacaranda (Jacaranda mimosifolia)**
  36. Chinese flame tree (Koelreuteria bipinnata)**
  37. Liquidambar/American sweetgum (Liquidambar styraciflua)**
  38. Southern magnolia (Magnolia grandiflora)**
  39. Sweet bay (Magnolia virginiana)**
  40. Palo verde (Parkinsonia aculeata)*
  41. Avocado (Persea americana)
  42. Mexican sycamore (Platanus mexicana)
  43. California sycamore (Platanus racemosa)*
  44. London plane (Platanus x acerifolia)
  45. Fremont cottonwood (Populus fremontii)*
  46. Black poplar (Populus nigra)*
  47. Black cottonwood (Populus trichocarpa)*
  48. Mesquite (Prosopis articulata)*
  49. Chinese wingnut (Pterocarya stenoptera)**
  50. Coast live oak (Quercus agrifolia)*
  51. Canyon live oak (Quercus chrysolepis)*
  52. Engelmann oak (Quercus engelmannii)*
  53. Valley oak (Quercus lobata)*
  54. English oak (Quercus robur)
  55. Cork oak (Quercus suber)
  56. Castor bean (Ricinus communis)
  57. Weeping willow (Salix babylonica)
  58. Goodding's black willow (Salix gooddingii)*
  59. Red willow (Salix laevigata)*
  60. Arroyo willow (Salix lasiolepis)* 
  61. African tulip tree (Spathodea campanulata)**
  62. Tamarix (Tamarix ramosissima)
  63. Japanese wisteria (Wisteria floribunda)
  64. Dense logwood/Shiny xylosma (Xylosma congestum)

Reproductive Host Species for KSHB (alphabetical by scientific name)

Click on a species name for symptom photos and other resources.

  1. Mimosa/Silk tree (Albizia julibrissin)
  2. Mulefat (Baccharis salicifolia)*
  3. Strawberry Snowball Tree (Dombeye cacuminum)
  4. Draft coral tree (Erythrina humeana)
  5. Avocado (Persea americana)
  6. California sycamore (Platanus racemosa)*
  7. Fremont cottonwood (Populus fremontii)*
  8. Black poplar (Populus nigra)*
  9. Coast live oak (Quercus agrifolia)*
  10. Cork oak (Quercus suber)
  11. Castor bean (Ricinus communis)
  12. Black locust (Robinia pseudoacacia)
  13. Red willow (Salix laevigata)*
  14. Arroyo willow (Salix lasiolepis)*
  15. Black Willow (Salix nigra)*

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