Mysterious Growth Found on Christmas Tree Turns Out to Be a Pine Gall

• Praying mantises lay egg cases (oothecae) outdoors in late summer or fall.

• Christmas trees are grown on outdoor farms, so branches can already have egg cases attached.

• The ootheca looks like a small brown, foamy, walnut-shaped lump, which is easy to miss.

• When the tree is brought indoors, the warmth can trigger early hatching.

Is it dangerous?

• ❌ Not dangerous to people or pets

• ❌ Not harmful to the tree

• ⚠️ Impractical indoors: the babies will scatter and won’t survive long without food

What to do if you find one

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