Laurel wilt: what the agencies record
What the USDA Forest Service Southern Region pest alert, NC State Extension, Clemson Extension and a Plant Disease note say about laurel wilt: the fungus and its ambrosia beetle, the laurel-family hosts, the states where it is recorded, the wilting and sapwood signs, the look-alike the sources name and the laboratory line.
Checked against the sources at the bottom of this page on October 8, 2026. Rules, fees and pay change: the source has the last word.
This page reports what the official source says. It is not legal advice: ask the office named here. It lists what the sources record about laurel wilt and does not diagnose any tree. None of the pages read gives laurel wilt a regulated or notifiable status. The list of other diseases is on the tree diseases page, and the reporting lines for the United States are in the United States report-a-pest guide.
At a glance
| Item | What the sources say |
|---|---|
| Pathogen | Harringtonia lauricola, a fungus, previously named Raffaelea lauricola. The USDA Forest Service Southern Region pest alert says it is transmitted by the redbay ambrosia beetle, Xyleborus glabratus. The alert says the beetle and fungus are native to southern Asia and that the beetle was first detected in Georgia in 2002. |
| Hosts | Trees and shrubs in the laurel family. The pest alert names redbay, sassafras, pondspice, bay laurel and avocado. NC State Extension adds swampbay and pondberry and says redbay and sassafras are most commonly infested. Clemson Extension names spicebush. |
| Where | The pest alert says redbay has died in large numbers in coastal areas from North Carolina to Mississippi, with detections also inland in Alabama, Louisiana, Kentucky, Tennessee, Texas, Georgia and Arkansas. Clemson Extension says the disease had reached eleven states in the south-east when it was written on May 20, 2021. NC State Extension says it has not been found in California. |
| Status | Not stated as regulated or notifiable on any page read. |
| Report to | NC State Extension asks that signs in an area not known to be infected be reported to NC State Extension or the NC Forest Service. For other places see the United States guide. |
How the sources say it spreads
NC State Extension says the beetle carries the fungus in small pouches on its mouthparts and that the fungus enters the tree when the beetle bores in. It says a single inoculation can cause disease and that the declining tree then draws more beetle attacks. Clemson Extension says isolated detections away from the main range are likely the result of infested firewood moving across state and county lines. The pest alert calls preventing spread by transporting firewood of the utmost importance, because management options are limited. For the wood-movement pages see moving wood and firewood.
Symptoms as the sources state them
- Leaves. NC State Extension says leaves wilt and turn olive green, reddish or brown. On deciduous hosts such as sassafras they fall early, and on evergreen redbay the dead leaves can stay on the branches for months, sometimes more than a year.
- Crown and timing. The pest alert and Clemson Extension say infected trees usually die within months while the crown is still full of dead brown leaves. Clemson Extension also lists stunted foliage.
- Under the bark. Both extension pages describe dark streaking or discolouration in the sapwood that shows when bark is removed. NC State Extension says it typically runs with the grain and starts as streaks.
- Beetle signs. NC State Extension and Clemson Extension describe small stacks of sawdust, like toothpicks, pushed out of beetle entrance holes. NC State Extension says the holes are very small and hard to spot, and that the toothpicks are not exclusive to this beetle.
- Season. A Plant Disease note confirming the disease on northern spicebush in Kentucky and Tennessee records leaf wilt, early fall leaf colour, dead leaves on branches and black streaks in the sapwood on plants observed in September 2020.
Look-alikes and lab confirmation
NC State Extension says the symptoms are similar to drought stress. It says that to confirm the disease, a streaked piece of sapwood can be cut out and sent to a diagnostic clinic. The Plant Disease note confirmed the fungus by culture from sapwood and DNA tests in a laboratory.
What the agencies publish for control
The pest alert and Clemson Extension say there is no cure once a tree has the disease, and list sanitation of infested material, by chipping or burning, and chemical treatments that may be effective for high value trees. NC State Extension says management options are extremely limited, that chipping may not always kill the small beetle, and that contact and systemic insecticides are ineffective once the beetle has bored in. It says fungicide treatment of high value avocado trees may be effective for about a year. Who may apply pesticides is covered on the pesticide licences page.
Credit
The USDA Forest Service Southern Region pest alert is a US federal publication. Everything here is restated in our own words from it and from the extension pages and journal note linked below.
Sources
- USDA Forest Service Southern Region, Pest Alert: Laurel Wilt, October 2019, as hosted by Southern Forest Health, read October 8, 2026
- NC State Extension Publications, Laurel Wilt Disease, read October 8, 2026
- Clemson University Home and Garden Information Center, Laurel Wilt Disease, May 20, 2021, read October 8, 2026
- Plant Disease journal note, first report of laurel wilt on northern spicebush in Kentucky and Tennessee, hosted by the USDA Forest Service, read October 8, 2026