Oak Wilt, Ceratocystis fagacearum

Scientific Name: Ceratocystis fagecarum
Common Name(s): Oak wilt


Research Summary
: Laura P.
Researching oak wilt was very difficult.  There were minimum resources so it was hard to find different information.  One thing that was surprising about oak wilt is that it is spread by firewood so I learned not to bring firewood into other states.  Also, I learned that oak wilt kills hundreds of oak trees every year. I would be scared to be a oak tree.

Identifying Characteristics

Signs of oak wilt include:

  • The green leaves will turn a green-brown, a bronze color then a shade of brown.
  • The top of the leaves will turn brown first.
  • Green leaves will fall off if the branch is infected.
  • The bark will turn a blue green.
  • Openings in the bark three to eight inches long.
Crown of Tree
  • If an oak tree is infected the crown of the tree will be different shades of brown or green. If it was injured by trauma or lighting the whole crown would be one shade of brown.

Taxonomy of Species
   Scientific Classification
 What That Classification Means
 Kingdom  Fungi  Eukaryotic, one- and many celled, don't move. All members obtain food
 from other organisms.
 Phylum  Ascomycota  Also called fungi. They produce reproducitve spores in specialized 
 sac-like cells called asci.
 Class  Sordariomycetes  Asci are in a flask-shaped ascoma (perithecium) with a pore at the top.
 Order  Microascales  This is a fruit bodies that are thin and affuseds a relatively small order of  
 mostly saprobic fungi that live in soil, rotting vegetation and dung.
 Family  Ceratocystidceae  Cerat Cantharellales. All species within the family have basidiocarps.
 Genus  Ceratocystis  Ceratocystis is a plant able to cause disease in many species.
 Species  Fagecarum  It is caused by the fungus Ceratocystis fagacearum.

Similar species include:

Location and Movement

Origin/ Native Range
  • Origin is not certain. One resource claims it is native to the US and originated in the upper Mississippi Valley. 
  • Researchers Jennifer Juzwik, Thomas C. Harrington, William L MacDonald and David N Appel believe that it may have originated from forests in Central America, South America or Mexico.
  • Juzwik surmised that the oak wilt fungus may have traveled with a yellow bellied sap sucker bird that had eaten a nitidulid beetle carrying oak wilt spores. Spores would have been deposited in a native US oak tree at some point during the bird's migration from South America to Canada.
  • In 1912, oak tree stands in Minnesota and Wisconsin were reported to die with symptoms similar to the oak wilt fungus.
Spread of Species
  • When the oak wilt goes on an oak tree it will grow pads made of sterile tissue which will go on the inner bark and outer wood. The pressure will cause the pads to expand, and the bark will split three to eight inches.
  • Then sap feeding beetles and squirrels will eat the oak wilt. The animals will get oak wilt on them and go to a different tree and the cycle starts over again.
  • One other way to spread oak wilt is if the oak trees are too close together and if one of the trees gets infected the roots combine and the oak wilt will spread through the roots.
Where is it now invasive?  Oak wilt is invasive in 21 states. Some of these states are: Texas, New York and Wisconsin. Oak
 wilt is in the midwest now in Appalachians and into south Texas.

Is this species in Maine?
Where has it been identified?
 Oak wilt is a threat to Maine. The closest place oak wilt is to Maine that has been identified is New
How was this species introduced?

Natural Environment
  • The hosts are typically live oaks such as shumard oaks, Spanish oaks, water oaks, black jack oaks, and other members of the red oak family.
  • White oak hosts are: Post oak, Bur oak, Mexican oak,White shin oak, Durand oak and other white oaks.
  • Other trees impacted may be American and European chestnuts, chinkapins and varieties of different apple trees.
Climate and Temperature Range
 Oak wilt thrives in hot and dry weather but likes cold and moist weather better.

Ecological Interactions  A parasite that infects and eventually kills different kinds of trees, mainly oaks.
 Gets nutrition by living off the host.
Consumed By
 Nitidulid beetles  and squirrels will consume it.

  • It kills oak trees and once the oak tree is dead all the other oak trees will get infected killing all the other oak trees.
  • Biodiversity of tree species and habitats of organisms depending on oak trees will be impacted.
 Human  People will cut down oak trees in their yard because they don't want to infest their yard wilt oak
  • When an oak tree is cut down it might have oak wilt on it. If a firewood company has oak wilt in their firewood the company will go out of business forcing people not to have a job.
  • Significant costs occur to remove infected trees.

 Biological  Nitidulid beetles and squirrels will eat oak wilt.
  • You can cut down oak trees to kill oak wilt and you can also cut the root grafts.
  • One more way to stop oak wilt is to install rootgraft barrier preventing oak wilt to travel underground.
 Cultural  Teach people to not bring in firewood from other states because it is one of the most
 common ways to spread oak wilt.
 Chemical  Alamo is a fungicide that will kill oak wilt.

Interesting Facts
  • Oak wilt will go for red oaks more often then white oaks.
  • It will start to wilt in June and July. Red oaks will wilt in three weeks.
  • It has been in central Texas for more than 64 years.
  • Half of the state of Wisconsin is covered in oak wilt.