
Associate Professor, Forest Health & Invasive Species Extension & Research @ClemsonUniv. Tweets about #foresthealth, #invasivespecies, #entomology, #forestry.
Clemson, SC
Joined July 2015
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Typical ambrosia beetle galleries in a dead sapling. The galleries are dark because symbiotic fungi - which the adult beetle carries in specialized little pockets - grow on the gallery walls. The larvae then eat the fungi (not the wood) to develop. #entomology #foresthealth
Dr. David Coyle retweeted
It’s spider season, y’all! Joro spider season, to be specific. 🕸️
@drdavecoyle answers your most common Joro spider questions in this Q&A 👉 blogs.clemson.edu/fnr/2025/1…
It's #SpookySeason... have you seen these creepy crawlies near you? 🕷️ This is the Jorō spider, an invasive species that first appeared in Georgia in 2014. It's since been found in 20+ SC counties, according to jorowatch.org.
If you have seen one (or many more) near you, the 2026 Joro Spider Spotting & Photo Contest is happening now through Sunday, Oct. 18! Snap a photo, submit a report and learn more about the contest here: jorowatch.org/season/
APPEARANCE
-Females are very large (3" legspan) with vibrant, yellow bodies and blue-green or silvery colored bands on their backs, plus red markings on their bellies. Legs are long and black with yellow bands.
-Males are much smaller (1" legspan) and appear in various shades of yellow and brown.
LIFE CYCLE
🕸️ April/May: Eggs hatch; tiny spiders are difficult to spot at this stage.
🕸️ Late summer: Spiders become noticeable as they approach maturity.
🕸️ November/December: Females lay eggs before the first major freeze; adult spiders die after the first freeze.
MANAGEMENT
-Jorō spiders are not likely to come inside your home, but you might see them on your house or on other structures nearby.
-These spiders can be eliminated using a registered acaricide.
-A stick or broom can be used to knock the spiders from their webs, and you can physically move them far from the original location as they are unlikely to return to that spot.
SEE A JORO?
Snap a picture! This helps researchers track the spread of this invasive species.
FAST FACTS
-Jorō spiders have lookalikes, including the yellow garden spider and the banded garden spider.
-They have not been shown to be a danger to people or pets.
-Reduced populations of native spiders have been documented where there are high Joro spider populations, which suggests a negative ecological impact.
-The central orb of a Joro spider's web is typically around 2' in diameter; the silk is yellow.
-Webs tend to be found at the edges of forests, in parks, on roadside plants or in yards on trees and on manmade objects like sheds.
Life cycle, management and more: hgic.clemson.edu/factsheet/t…
General information: naisma.org/2024/07/03/the-jo…
Addressing common concerns about Joro spiders: news.clemson.edu/studies-sho…
JoroWatch is officially on! Submit your Joro spider photos for a chance to win prizes (and help science)!
Save the dates from October 12–18 and prepare to report your Joro spider sightings while showcasing your photography skills.
To keep informed about contest specifics, rules, and updates, make sure to follow us and check out JoroWatch.org.
Grow more trees, you say? Often where trees would grow best and make the most $$ are also the places best suited for agricultural crops. In the Midwest, corn/soybeans/sugar beets/whatever are more valuable than trees. It all boils down to economics.
sciencedirect.com/science/ar…
Jay and I conduct "caterpillar walks" every year, and I know this #webinar will be engaging, entertaining, and have lots of amazing caterpillar pictures.
Register for free at: scwf.org/events/introduction…
#caterpillar
Interested in #invasivespecies anyone? Join @scwildlifefed and me for a free webinar tomorrow!
Check out our shiny new paper on Anoplophora beetles! We summarize the history and what's known about this group of global invaders and perpetual pests.
link.springer.com/article/10…
Dr. David Coyle retweeted
Join us January 14th at the Clemson Extension TEACH Center for an Urban Tree Health Workshop! 🌲
Pesticide and/or Continuing Education credits are offered and lunch is included! ✍️
eventbrite.com/e/urban-tree-…
Not tryin' to brag but they DID call me one of their favorite nature experts...
Can woolly bear caterpillars predict the weather? foxcarolina.com/2025/11/04/c…
Dr. David Coyle retweeted
.@drdavecoyle has a few things to share about Jorō Spiders... 🕷️
If you have to manage Jorō spiders on your property, a broom or stick works just fine. 🧹
If a Jorō does get on you, try not to freak out; the odds of getting bitten are extremely low. 🕸️
entomologytoday.org/2025/10/…
Dr. David Coyle retweeted
Two new studies offer good news about Jorō spiders: Common spider control products are effective against them, and their bites are both unlikely and generally harmless. /by @drdavecoyle buff.ly/VpgUMZL
Yes, there are more big spiders than usual this year (it's the weather). Yes, they're venomous (as are all spiders) but they're not poisonous. No, they don't want to come in your house. Also no, they don't want to bite you. Hat tip to Gayoung Lee @gizmodo.
gizmodo.com/theyre-huge-they…
Are Joro spiders big? Yep. Are they colorful? Also yep. But are they dangerous? Nope. These #invasivespecies are here to stay, though, so best get used to 'em.
.@drdavecoyle, Associate Professor of Forest Health and Invasive Species at @ClemsonUniv, recently co-authored two papers addressing some key concerns of the public when it comes to Joro spiders. 🕷️
“These spiders are easy to manage...” ✍️
news.clemson.edu/studies-sho…
Dr. David Coyle retweeted
Oasis of Kudzu
Like a lamp at night or a spring when it’s dry
So the kudzu appears to the spore as it flies
It’s tired and windswept and ready to rest, and
Maybe eat some of the plant it loves best
Phakopsora sighs as it settles on leaves
After it’s ride on the blustery breeze
The hot, humid, dog days of summer means the #invasivespecies kudzu is in out and in all it's glory. Not familiar with this invasive weed? Wondering why we care about it? Curious as to how to get rid of it? This video might just help...
youtube.com/watch?v=q0KjmBMU…
The hot, humid, dog days of summer means the #invasivespecies kudzu is in out and in all it's glory. Not familiar with this invasive weed? Wondering why we care about it? Curious as to how to get rid of it? This video might just help...
youtube.com/watch?v=q0KjmBMU…
Privet is one of the most common invasive plants in eastern North America, but fear not! There are several effective management options available! Hat tip to @UntamedScience for helping to make this awesome video.
youtube.com/watch?v=cdZMCZ6M…
Dr. David Coyle retweeted
“I would argue that the Emerald Ash Borer is the most invasive forest pest of this generation,” says @drdavecoyle, Associate Professor of Forest Health and Invasive Species 🌲
postandcourier.com/spartanbu…
I got a thing.
Four of our faculty members were honored at the 2025 @ClemsonUniv Spring Awards ceremony on Monday! 🏅
Congratulations to @drdavecoyle, @GuidoSchnabel, @SuseelaVidya & Elizabeth Cieniewicz. We are so grateful for your contributions to our college. 💜
🔗 news.clemson.edu/faculty-sta…
Dr. David Coyle retweeted
TABLE ROCK, PERSIMMON RIDGE FIRES DECLARED 100% CONTAINED
Forestry Commission officials announced Tuesday the Table Rock Complex fires, which burned through 15,000-plus acres in Greenville and Pickens counties and part of North Carolina, have been fully contained.
The decision to declare the fires 100 percent contained followed another round of significant rainfall that moved through the area Monday. The Table Rock Fire ignited March 21 and burned 13,845 acres before being contained, while the Persimmon Ridge Fire burned 2,128 acres after igniting March 22.
Resources remaining on the fires will continue to focus on suppression repair, which involves stabilizing exposed soil with seed and straw to prevent erosion and remove dirt and debris from stream crossings. Water bars will also be installed on containment lines to divert surface water runoff back into the woods.
The fires will be considered controlled once it has been determined that firefighting resources are no longer needed at the site.
Dr. David Coyle retweeted
FORESTRY COMMISSION ISSUING STATEWIDE RED FLAG FIRE ALERT
The South Carolina Forestry Commission is issuing a statewide Red Flag Fire Alert, effective immediately until further notice. The Commission plans to reevaluate conditions Sunday.
The alert is being issued to strongly discourage people from burning outdoors when weather conditions present an elevated risk of wildfire.
A cold front moving across the state today will usher in low relative humidities throughout the weekend, accompanied by sustained periods of gusty winds. While the frontal passage may result in precipitation in some areas today, the expected amounts of rainfall will not be significant enough to remediate already-dry fuels on the ground over much of the state.
A Red Flag Fire Alert does not prohibit outdoor burning, provided that all other state and local regulations are followed, but the Forestry Commission uses the alert to strongly encourage citizens to voluntarily postpone any such burning until the alert is lifted. Land managers who are considering conducting prescribed fires should take extra care if they choose to burn under a Red Flag.
“The combination of wind, low relative humidity and dry fuels is very favorable for wildfire ignitions, so we ask that people who don’t have to burn to hold off until these conditions subside,” said SCFC Fire Chief Darryl Jones. “The dramatic uptick in wildfires across the state over the last two months were in large part the result of exactly these typical springtime weather patterns.”
The purpose of Red Flag Fire Alerts is twofold: in addition to discouraging people from doing any outdoor burning, it also helps to reduce the strain on local fire departments and other first responders who need to remain available for other emergencies.
SCFC firefighters responded to 280 wildfires in February alone, above the five-year average for the second month of the year. The agency has already recorded 277 wildfires in March. Historically, wildfire occurrence in South Carolina is greater in March than in any other month.
Although a Red Flag Fire Alert does not ban outdoor burning, it does trigger certain county or local ordinances that restrict outdoor fires, so residents should contact their local fire departments to check whether such restrictions apply in their areas. The alert will remain in effect until lifted by the Commission, whose fire managers will continuously monitor the situation.
See the release here: scfc.gov/wp-content/uploads/…
Find the Gaps. Fill the Map.
It's Callery pear season, and we're asking YOU to help us document this #invasivespecies' whereabouts. We all know this plant is a scourge and #foresthealth threat, and knowing where it is is the first step in management.
invasivepearwatch.org/


























