Unknown gall.

Quercus chrysolepis
Leaf galls, integral
Conical, red, 2-10 mm long, surface above it depressed. Fig 170. The terminal cluster of similar galls in Fig 126 may be the same thing.

Fig. 126. Q. chrysolepis. This is thought to be a cluster on an aborted leaf. A single one on a leaf is shown in Fig. 170.

Fig 170. Conical, red, on under side of leaf of Q. chrysolepis; above it the leaf surface is depressed. Single or in a cluster on aborted leaves so that it looks like a stem gall (Fig.126). Full-grown in June. Those collected in September to December have been empty.

[Undescribed]

Quercus wilcoxii [chrysolepis]
Leaf galls
Integral
Fig 135.
Conical, red, 2-10 mm high, surface above it depressed.

Heteroecus pacificus (bisexual generation)

Bisexual generation galls are conical, thorn-shaped, red-wine colored, monothalamous, and often in clusters.

Hosts:
Quercus chrysolepis
Quercus vacciniifolia

Heteroecus pacificus [sexgen]

Host: Quercus chrysolepis

Description of Gall: (Fig. A) A conical, thorn-shaped, monothalamous or single chambered gall growing from the undersurfaces of the leaves. The leaf surface immediately above the gall is darkened and slightly depressed. Galls may occur singly or in groups or clusters that may be so numerous that the developing leaf is completely aborted with the resulting growths resembling twig galls. Often the new twigs are killed by heavy infestations. Development is quite rapid with the galls containing large larvae in late May and pupae in June. The young galls are pale red in color when they first appear but darken to deeper red or reddish-purple as they mature. Adults of both sexes begin to emerge the last few days of June and continue to appear until late July. Some of the gall clusters yield only males whereas others yield only females, indicating that certain gall clusters result from female wasps that lay eggs producing only the haploid males whereas others produce the eggs that develop into the diploid females. Male specimens outnumbered the females three to one.

Range: La Crescenta, Pasadena, Switzer's Camp, Mt Wilson, Chilao in the San Gabriel Mountains, CA