SCRAPEEgg Mass Season

What You're Looking For

SLF egg masses look like dried mud or putty — a brownish-gray blob about 1 inch long with a waxy coating. Fresh ones look like someone smeared peanut butter on bark. Old ones (after the coating wears off) show neat rows of 30–50 seeds.

• ▸Brownish-gray, roughly 1 inch long
• ▸Waxy, mud-like coating when fresh
• ▸Rows of 30–50 seeds visible when coating is gone
• ▸Found on tree bark, outdoor furniture, vehicles, stone walls — any smooth surface
• ▸Favorite trees: Tree of Heaven, black walnut, river birch, grapevines

What To Do Right Now

1. 1

   Get your kit

   A credit card or plastic scraper, a disposable container, and a splash of hand sanitizer or rubbing alcohol (70%+). The alcohol kills eggs on contact. Soapy water works too.

2. 2

   Find every mass on your property

   Check all tree trunks, patio furniture, deck railings, outdoor grills, fence posts, stone walls, and parked vehicles. Don't forget the underside of furniture. SLF lays on any smooth surface within reach.

3. 3

   Scrape into alcohol

   Scrape the egg mass directly into your container of hand sanitizer or rubbing alcohol. The key: scrape INTO the container, not onto the ground. Eggs scraped onto soil can still hatch.

4. 4

   Destroy the container

   Seal it up and trash it. Don't compost — some eggs may survive. If you don't have alcohol handy, scrape into a bag, zip it shut, and freeze overnight.

5. 5

   Report what you found

   Log your find on iNaturalist or use our sighting form. This data matters — it helps track spread patterns and informs where community scraping events are most needed.