Mercury News: Will thousands of oak leaf galls produce a mass invasion of wasps? Will thousands of oak leaf galls produce a mass invasion of wasps? Marin Independent Journal: Oak leaves turning brown?

Understanding the Context

Could be the two-horned oak gall wasp Many coast live oak (Quercus agrifolia) trees are showing unusual browning in their canopies in the last month or two. If you look carefully, you may see small, crescent-shaped galls forming on the ... DEAR JOAN: There has been much discussion on Nextdoor about oak galls lately, mostly about how the galls are harmless to the tree and that they’re quite prevalent this year on oak trees around ... Hundreds of species of small wasps called gall wasps live in the forests of North America.

Key Insights

Hundreds more species of them are spread worldwide. In Southeast Missouri oak trees are a favorite host plant ... The Bulletin: Exploring the Last Green Valley: The fascinating life of oak gall wasps Exploring the Last Green Valley: The fascinating life of oak gall wasps