Rio Grande River near McAllen, Texas. ARS scientists are reducing the amount of giant reeds growing along the border of the river. (John Goolsby, D3659-1)
An arundo gall wasp deposits eggs into the main stem of a giant reed. (John Goolsby, D3660-1)
A gall wasp larva (bottom) chews its way through the cross section of an Arundo donax stem. (John Goolsby, D824-1)