Landscape Report


Pack Memories, Not Invasive Pests This Fall

The dry, cool weather of September heralds the beginning of the fall camping season. Although camping is a great way to reconnect with family and nature, traveling to and from your campsite can give invasive insects and plants a free ride to a new forest. Without the help of people, most exotic invasive insects spread less than 10 miles each year. If you accidentally pack them with you on your way to or from your trip, they can move thousands of miles.

The following pests are particularly good at hitch hiking in the fall. Keep an eye out for them when traveling or moving gardening equipment long distance.

Spotted lanternfly–  Adults will lay eggs from September until the first frost on just about anything from telephone poles and tree bark to under the bumper of your car, camper or mower. Their outsized capacity to suck plant sap and excrete sticky honeydew creates sticky leaf surfaces that become covered with black sooty mold and stinging insects.  Although adults and nymphs are distinctively spotted and colored, the eggs are mud colored and difficult to find.

Spongy moths – Like spotted lanternfly adults of this moth will lay eggs on tree trunks, under branches and on anything that is outside during the month of July when they lay their eggs. The caterpillars of this insect (formerly known as gypsy moths) have a huge appetite for oak leaves, maples, pines and hemlock.  In outbreak years like the summer of 2022 they can completely defoliate millions of acres of forest.   Although the blue and red spotted caterpillars are quite distinctive, the dun-colored egg masses are difficult to find.  If you are camping during July in heavily infested areas, you can easily bring the egg masses back with you.

Wood borers – During the autumn many invasive destructive borers like Asian longhorned beetle, and emerald ash borer as well as vectors of Thousand cankers disease are in the larval stage beneath the bark.  For this reason, moving firewood long distances to and from campsites risks spreading these pests. Don’t share the devastation wrought by emerald ash borer and other invasives by moving firewood.


Soil borne pathogens –Sudden oak death and boxwood blight are two of many pests threatening plants in Indiana forests and landscapes. Spores of these pathogens can be spread by hikers walking over contaminated areas. Be sure to wash your boots!

Jumping worms– Are a new invasive worm that is starting to make its way into Indiana. It moves between gardens when muddy equipment is loaned, compost is shared, or when plants are traded with soil.  This new invasive worm can strip the organic matter from productive garden soil and give it the inhospitable texture of coffee grinds. Trading plants with soil is not recommended in areas where these worms have been found.

Japanese siltgrass

Small weed seeds of invasive weeds like Japanese stiltgrass can be abundant in the fall and moved in bits of soil. (Photo c/o Knox County SWCD)

Weed seeds- Many invasive weeds can be spread by seeds in contaminated soil. Japanese stiltgrass (Microstegium vimineum)is a good example of a weed that produces small seed that can transported in mud on equipment that is moved in the fall.

Follow these tips to stop invasive hitch hikers.

  1. Check Conditions. If you are traveling to or from an infested area you may be giving invasives a ride. In Indiana,  the Department of Natural Resources Department of Entomology and Plant Pathology (DEPP), maintains  a pest of concern website to help you find out where pests are a problem. Nationally, the USDA APHIS maintains a website for locations of pests by state.
  2. Don’t Move Firewood. Collect or purchase your firewood within 30 miles of where you plan to use it. Trees inside of this radius are exposed to the same types of pests and pathogens so there is a lower risk of spreading something new. If you move this wood too far (more than 30 miles) you risk moving a pest or pathogen to a new area where they can attack and kill new trees. By not moving wood far from where it is collected you can prevent the spread of these pests to new, un-infested areas
  3. Wash muddy boots, dirt filled tires, camping, gardening, and farming equipment. Seeds of invasive weeds and the spores of plant diseases can become trapped in mud and released to new areas when moved.   Always remove mud before you travel to a hiking area and immediately after your hike. Aside from the added benefit of keeping the interior of your car clean, any seeds or spores you may have picked up on the trail will stay near where you collected them.  The same rule applies to mountain bikers, 4-wheelers, gardeners and farmers.
  4. Inspect your car or camper before you return from visiting areas where spotted lanternfly have been reported . Adult female spotted lanternflies will lay their eggs on vehicles and campers from the beginning of September through the time of the first frost. Be sure to give your camper or car a good inspection before you return.
  5. Take your car or camper to the car wash, or give it a good soapy power wash at the of the season to take off any spongy moth or spotted lanternfly egg masses. This will help kill any egg masses you missed before they hatch the following spring. Because the killing power of your washing action alone is unclear, it is best to hand remove any egg masses you see and dump them into a bucket of sudsy water before you wash you vehicle.


Finally, if for some reason you find invasive pests during your Indiana travels report them by calling 866-NO EXOTIC (866-663-9684) or send an email (with a photo of the insect if possible) to For more information about this or other invasive pests facing Indiana see


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