Butterflies & Moths (Lepidoptera)

Tobacco hornworm

In the fall, a resident brought us a massive hornworm he had found on a tomato plant in his garden (see photo). Hornworms are the larval (caterpillar) stage of a moth with a wingspan of up to five inches. Despite their prodigious size, hornworms are so expertly camouflaged that they often go unnoticed (by humans). We fed our green giant for a few days, and it methodically munched its way through leaf after leaf of tomato foliage. A few days later, it decided that it had had enough, and began the process of pupation.

Our hungry green giant, the tobacco hornworm

Hornworm pupa

The hornworm was not as healthy as we thought!

Oak moth

Oak moths are the adult stage of the California oakworm. These moths may be abundant in late spring/early summer and again in the fall, and can be observed fluttering around coast live oak trees (Quercus agrifolia) in the late afternoon.

An adult California oak moth

Two pupal cases- the yellow one is newly formed

California oakworm (larvae)

California oakworms are the larval (caterpillar) stage of the oak moth. These caterpillars feed on oak leaves, especially those of the coast live oak (Quercus agrifolia). In some years, populations may become very high and certain trees may become completely defoliated. According to the University of California, healthy oaks can generally survive even heavy infestations, so control measures against these caterpillars are not usually necessary.

California oakworm caterpillars (larvae)

Oakworm frass (droppings)

Subscribe to RSS - Butterflies & Moths (Lepidoptera)