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Convergent lady beetles, Hippodamia convergcns Cuerin-Meneville, collected from aggregations in California were released for control of melon aphids, Aphis gossypii Clover, infesting potted chrysanthemum, Dendranthema grandiflora (Tzvelev) 'Hurricane,' outdoors. Most beetles dispersed from plants within 1-3 d after a single release during May 1993 and July and September 1993 and 1994. Most dispersing beetles left the study area, although some moved within release plots to adjoining plants or dispersed to nearby plots within =40 m. Aggregation-collected beetles that were allowed to drink and fly in a screen tent for 7-10 d before release and insectary-reared beetles dispersed more slowly than aggregation-collected beetles that were stored at 4-lO o C until the day of release. Although beetles dispersed within days, releases significantly reduced aphid densities during all trials. A single release of 34-42 adult H. convergem per pot provided 25-84% aphid control, calculated according to the Abbott metilOd. Each beetle consumed =25-170 melon aphids per day. There was a density-dependent functional response in predation; beetles consumed more aphids when released on plants with higher aphid densities. Release of commercially available convergent lady beetles can provide augmentative control of relatively high aphid densities on small potted plants. KEY WORDS Hippodamia convergellS, Aphis gossypii. Dendranthema grandiflora, inundative control THE CONVERGENT LADYbeetle, Hippodamia convergens Guerin-Meneville, is widely released for aphid control. Large aggregations in the Sierra Nevada allow convergent lady beetles to be readily collected and packaged for sale in nurseries, garden supply catalogs, and other outlets across the United States. No data are available, but our commercial supplier reportedly sells ""20,000 liters (""5,000 gal) of convergent lady beetles each year and estimates that these sales are ""10% of the California market. Because 1 gal contains 70,000-80,000 beetles, several billion convergent lady beetles are apparently collected and sold each year. The University of California has histOrically recommended against releasing aggregation-collected convergent lady beetles because releases were believed ineffective (Moore and Koehler 1981, Hagen 1982). The recommendation against releases was based mostly on observations that H. convergens collected from aggregations dispersed soon after being released. Davidson (1919, 1924) released marked beetles in barley, Hordeum vulgare L., and wheat, Triticum sp., and found that only ""10% of beetles remained after 1 wk. Eddy (1939) lIPMEducationandPublications, Statewide IPMProject, Universityof California, Davis, CA95616-8620.

We investigated seasonal development of the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and physical conditions of the phloem within a preferred host species, coast live oak, Quercus agrifolia Née. We sampled infested trees on a monthly basis at two sites in southern California throughout 2011. Measurements of an exposed portion of the head capsule, the peristoma, indicated that there were four larval instars. Pupae and teneral or mature adults were found within trees from April through August. Adults were captured in flight between May and mid-October, with peak flight from July through August. Within-tree A. auroguttatus prepupal mortality did not differ between sites and increased significantly from 3 ± 3% in January to 36 ± 9% in March (mean ± SE). Prepupae were present in trees throughout most of the year, which made it difficult to determine generation time; it was likely 1 yr for the majority of individuals, and possibly longer or shorter than 1 yr for others. Seasonal A. auroguttatus development, according to within-tree development and adult trap catch, was apparently 2 mo ahead at one site, which had a greater past and current level of A. auroguttatus infestation compared with the other. There was also evidence at the more severely infested site that within-tree A. auroguttatus population densities were positively related to proportion of dying phloem tissue. This suggested that the level of current infestation affected host tree condition, or that dying tissue was more suitable for larval development.

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