12-Inch White "Worm" on Birch Tree: Identification Needed

North Vancouver, BC: 12-inch skinny white worm/snake dangling from birch tree near sensor light. 50°F evening. Two spotted.

Likely Candidates

1. Giant Silk Moth Caterpillar

• Polyphemus, Cecropia, Luna moth larvae: Large, pale green/white, up to 4"
• But 12" is too large for any native caterpillar

2. Parasitic Nematode "Mass"

• Mermithid nematodes emerge from insects as long white strands
• Can reach 12"+ but very thin (hair-like)

3. Small Snake

• Sharp-tailed snake, rubber boa, garter snake juvenile: 12" plausible
• Attracted to warmth of sensor light
• Climb trees for birds/eggs

4. Miscellaneous

• Spider egg sac ballooning in wind
• Fungal rhizomorph (root-like strand)
• Debris/string caught on branch

Action Required

Photo essential for identification. Without image, speculation only. Take clear photo with size reference (coin, ruler). Contact:

• BC Ministry of Agriculture Plant Health Lab
• Local Master Gardeners
• iNaturalist community (photo upload)

Most 12" white "worms" on trees in BC are small snakes—harmless and beneficial.