The tubular gall is more common in this area than is the gall of Bucculatrix fusicola. It occurs on Helianthus annuus, and as yet has not been found on other composites in the vicinity [of Austin, TX]. In this area there is considerable variation in the size, structure and the position of the galls on the plants... They have been found to range from 10 to 50 mm in length. In many cases the galls occur as polythalamous structures of ten to twenty-five divisions... Single galls are sometimes collected, but these are most often near the polythalamous galls on the main axis of the plant. Both types of galls are also found at the bases of and on the lateral branches of the sunflowers. Occasionally single galls are formed in the leaf axil or on the petiole, or even on the involucre of the flowers. Double or triple galls sometimes develop in these latter locations, but they rarely have more divisions than this.

[includes much more info re: the biology of this species]

Trishormomyia helianthi Brodie

This species produces on Helianthus more or less cylindrical flask-shaped galls (fig. 49, pl. II, fig. 2) having a length of 10 to 25 mm and a diameter of from 1.5 to 5 mm. There may be one to ten galls in an axile, firmly attached to the stem by an expanded base and projecting in various directions, usually upwards, often at right angles to the stem, and occasionally downward. They occur on the upper third of the stems of H. decapetalus and H. divaricatus. They are also found on H. annuus. The gall has been collected about Toronto, Canada, Evanston, Ill., and Salt Lake City, Utah. It is local at Evanston Ill, occuring in September (L. H. Weld).

We reared O. helianthi from tubular (flasked-shaped) bud galls on 4 species of Helianthus... This species was originally reared from H. decepetalus and from H. divaricatus in Canada (Brodie 1894). We collected O. helianthi in auxiliary bud galls on H. annuus at Muenster, TX. Olpodiplosis helianthi is also known from H. tuberosus in Blackjack, MO, and from H. strumosus in Canada...

The tubular gall is more common in this area than is the gall of Bucculatrix fusicola. It occurs on Helianthus annuus, and as yet has not been found on other composites in the vicinity [of Austin, TX]. In this area there is considerable variation in the size, structure and the position of the galls on the plants... They have been found to range from 10 to 50 mm in length. In many cases the galls occur as polythalamous structures of ten to twenty-five divisions... Single galls are sometimes collected, but these are most often near the polythalamous galls on the main axis of the plant. Both types of galls are also found at the bases of and on the lateral branches of the sunflowers. Occasionally single galls are formed in the leaf axil or on the petiole, or even on the involucre of the flowers. Double or triple galls sometimes develop in these latter locations, but they rarely have more divisions than this.
[includes much more info re: the biology of this species]

Tubular gall on all plant parts, usually at nodes...Olpodiplosis helianthi (Brodie)

Galls are mono- or polythalamous and highly variable in shape and length. The open, reflexed ends are filled with fine hairs. Adults emerge through the open end in late spring and in summer, so this species is at least bivoltine. Hosts: H. annuus, H. decapetalus, H. divaricatus, H. strumosus, H. tuberosus.