Rhabdophaga batatas, Walsh. Host Salix humi-Us, Marsh. A nodule-like swelling of the stem of the prairie willow. Very variable in size and shape.
Rhabdophaga strobiloides, Walsh. Host Salix cordata, Muhl. A top-shaped mass of leaves, produced by a shortening of the stem axis of the host, constitutes the principal mass of this gall.
Eurosta solidaginis, Fitch. Host Solidago canadensis, L. The gall consists of a spherical swelling of the stem of this golden-rod. When dry it is pith-like in structure throughout.
Podapion gallicolla, Riley. Host Pin us resinosa, Ait. An ellipsoidal to spherical swelling of the branches of red pine.
Saperda concolor, Lee. Host Populus candicans, Ait. A more or less regularly ellipsoidal swelling of the stem or branches of the host. The producer emerges early in May.
Order HYMENOPTERA. Family Tenthredinidae.
Sawfly gall producers infest only the willows.
Euura Salix gemma, Walsh. Host Salix humilis, Marsh. This gall is produced by the swelling of a lateral bud.
Euura Salix ovum, Walsh. Host Salix cordata, Muhl. A monothalamous gall consisting of an elongated oval swelling on one side of a twig.