Periodical cicada Brood X (10) will emerge in the spring of 2021 in Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Washington D.C.
The last time this brood emerged was in 2004.
What, when, where, and why:
Billions of these:
- Cicada insects with a 17-year life cycle.
- Some people call them “locusts” but they’re really cicadas.
- Which species: All three 17-year species, Magicicada septendecim, Magicicada cassini and Magicicada septendecula. How to tell the difference between the species.
- NOT the green ones that arrive annually.
When: Typically beginning in mid-May and ending in late June. These cicadas will begin to emerge approximately when the soil 8″ beneath the ground reaches 64 degrees Fahrenheit. A nice, warm rain will often trigger an emergence. Back in 2004, people began reporting emergences around May, 13th.
Other tips: these cicadas will emerge after the trees have grown leaves, and, by my own observation, around the same time Iris flowers bloom:
Places = cities, towns, communities, parts, etc. where people told us they emerged back in 2004.
- Delaware counties: Kent, Sussex
- Delaware places: Newark, Wilmington
- Georgia counties: Union, White
- Georgia places: Blairsville, Ellijay, Norcross
- Illinois counties: Edgar, Clark, Crawford, Vermilion
- Illinois counties: Marshall
- Indiana counties: Brown, Clark, Clay, Crawford, Daviess, Dearborn, Dubois, Fountain, Gibson, Greene, Jackson, Jefferson, Jennings, Lawrence, Martin, Monroe, Montgomery, Orange, Owen, Parke, Perry, Pike, Ripley, Spencer, Sullivan, Vanderburgh, Vigo, Warrick
- Indiana places: Bloomington, Brookville, Clinton Falls, Dillsboro, Fishers, French Lick, Indianapolis, Lawrenceburg, Lexington, Martinsville, McCormick’s Creek State Park, Nashville, North Vernon, Skiles Test Park, Spencer
- Kentucky counties: Boone, Breckenridge, Bullitt, Carroll, Daviess, Gallatin, Grayson, Henry, Jefferson, La Rue, McLean, Muhlenberg, Nelson, Ohio, Oldham, Trimble
- Kentucky places: Big Bone Lick State Park, Covington, Dayton, Florence, Ft. Thomas, Hebron, Louisville.
- Maryland counties: Allegany, Anne Arundel, Baltimore, Carroll, Cecil, Garrett, Harford, Howard, Montgomery, Prince Georges, Washington
- Maryland places: Abingdon, Annapolis, Aspen Hill, Baltimore, Bel Air, Beltsville, Bethesda, Bowie, Brooklandville, Brooklyn Park, Catonsville, Chevy Chase, Clinton, College Park, Columbia, Crofton, Cumberland, District Heights, Eldersburg, Elkridge, Elkton, Ellicott City, Fair Hill, Fallston, Forestville, Gaithersburg, Gambrills, Germantown, Glen Burnie, Glenelg, Greenbelt, Gwynn Oak, Hagerstown, Hanover, Havre De Grace, Hillcrest Heights, Hunt Valley, Hyattsville, Hydes, Jessup, Landover Hills, Laurel, Lutherville, Odenton, Oella, Owings Mills, Pikesville, Potomac, Randallstown, Reisterstown, Riverdale, Rockville, Severna Park, Sharpsburg, Silver Spring, Takoma Park, Timonium, Towson, Wheaton
- Michigan counties: Hillsdale, Washtenaw
- Michigan places: Ann Arbor, Canton, Quincy
- North Carolina counties: Cherokee, Surry, Wilkes
- North Carolina places: Morganton, Murphy
- New Jersey counties: Burlington, Hunterdon, Mercer, Salem
- New Jersey places: Browns Mills, Harmony, Hillsborough, Holland Township, Kingwood Township, Merrill Creek Reservoir, Milford, Monmouth Junction, Morristown, Pennington, Princeton, Sourland Mountain
- New York counties: Suffolk
- New York places: Stony Brook, LI
- Ohio counties: Defiance, Franklin, Greene, Hamilton, Logan, Montgomery
- Ohio places: Anderson Twp, Battelle Darby Park, Bellbrook, Cincinnati, Columbus, Defiance, Delaware, Delhi Twp, Dublin, Fairfield, Galloway, Hamilton, Kettering, Lewisburg, Lockland, Miamisburg, Olmsted Falls, Oxford, Springfield, St. Bernard, West Carrollton, West Chester
- Pennsylvania counties: Adams, Bedford, Berks, Bucks, Chester, Columbia, County, Cumberland, Dauphin, Franklin, Fulton, Huntingdon, Lancaster, Lehigh, Luzerne, Lycoming, Mercer, Montgomery, Northampton, Perry, Schuylkill, Somerset, York
- Pennsylvania places:Archbald, Artemas, Bedford, Carroll Valley, Coopersburg, Dinosaur Rock, Downingtown, Gettysburg, Green Lane, Kintnersville, Lake Nockamixon, Lancaster, Lititz, Malvern, Mertztown, Mohnton, Mt Gretna, Oaks, Oley, Perkiomenville, Phoenixville, Pittston, Quakertown, Red Lion, Roaring Spring, Solebury, Spring Mount, Stewartstown, Topton, Upper Black Eddy, Warwick Park
- Tennessee counties: Blount, Greene, Hamblen, Jefferson, Knox, Roane, Sumner, Wilson
- Tennessee places: Copperhill, Farragut, Fayetteville, Knoxville, Oak Ridge.
- Virginia counties: Arlington, Clarke, County, Dulles Smithsonian National Aircraft and Space Museum, Fairfax, Fauquier, Frederick, Shenandoah, Warren, Winchester
- Virginia places: Alexandria, Annandale, Arlington, Ashburn, Centreville, Chantilly, Clearbrook, Doswell, Dunn Loring, Fairfax, Falls Church, Franconia, Haymarket, Herndon, Lorton, Lovettsville, Manassas, Oakton, Reston, Springfield, Vienna, White Post, Winchester.
- West Virginia counties: Berkeley, Grant, Hampshire, Hardy, Jefferson, Mineral, Morgan
- West Virginia places: Martinsburg, New Creek
- Washington D.C.
More Location Tips:
- Reports of Brood X cicadas that emerged early in 2017.
- County data is from the Cicada Central Periodical Cicada Record Database. Cities come from May 2004 reports and June 2004 reports.
- Not sure? Ask someone in your community who lived there 17 years ago.
Why: Why do they stay underground for 17-years? The prevailing research suggests they’ve evolved a long, 17-year lifecycle to avoid predators that can sync up with their lifecycle & emergence. Why are there so many?! Research suggests that their huge numbers allow them to overwhelm predators, so enough of them will live on to breed and perpetuate the brood.
More facts and fun:
- Use the correct image when talking about these cicadas.
- Use the Periodical Cicada Emergence Checklist for the Maximum Magicicada Experience.
- All cicada questions that are frequently asked.
- A video to help you tell the difference between the species.
- The 17 Most Interesting Periodical cicada facts.
1907 Map from Marlatt, C.L.. 1907. The periodical cicada. Washington, D.C.: U.S. Dept. of Agriculture, Bureau of Entomology.
Some Brood X “stragglers” emerged early in 2020. See where on the map below: