willow galls

Member of arthropods (phylum Arthropoda)
animals (kingdom Animalia)
galls

---

Gallformers.org lists particular species of willows (genus Salix) as hosts for each parasite, but it’s always a bunch of species. That makes me think that their lists might not be exhaustive, and in any case I’m not good enough at distinguishing willows to do anything with that info.

willow rosette gall midge
Rabdophaga salicisbrassicoides

• forms a leafy bundle on or around a branch of willows (genus Salix)

willow cone gall midge
Rabdophaga strobiloides

• forms at the end of twigs of willows (genus Salix)
• gray-hairy over brown pinecone shape

willow rose gall midge
Rabdophaga rosaria

• forms a green leafy bundle on tips of branches of willows (genus Salix)

willow redgall sawfly
Euura proxima

• forms on leaf surfaces of willows (genus Salix)
• lumpy red blister(s)

arroyo willow stem sawfly
Euura lasiolepis

• forms within branches of arroyo willow (Salix lasiolepis)

willow stem sawfly
Euura exiguae

• forms within branches of willows (genus Salix)

---

6 observed taxons / 6 unobserved taxons / 1 key

Chris’s observations: 27 (1 is research grade)

Locations:

• Murray Ranch SP: 8
• Coal Creek OSP: 4
• Coyote Hills RP: 4
• Sweeney Ridge National Recreation Area: 3
• Lake Chabot RP: 2
• Sibley Volcanic RP: 2
• Alum Rock Park, San Jose
• Bear Creek Redwoods OSP
• San Bruno Mountain State & County Park
• Waterdog Lake & Open Space

Months:

• Mar.: 1
• Apr.: 1
• May: 0
• Jun.: 1
• Jul.: 3
• Aug.: 12
• Sep.: 5
• Oct.: 2
• Nov.: 2

For more details, use advanced search.

---