most larvae of this species obtain their characteristic toxic compounds from their diet, which can vary from foxglove (and members of the daisy family) to species in completely other plant families, such as plantago. Plant deterrents to herbivory Because of A. caja’s generalist diet while in the larval stage, it is subject to a wide variety of plant defenses. One study tested plant health with and without beneficial fungus known as Arbuscular mycorrhiza (AM), and saw that Plantago lanceolata with beneficial fungus produce more anti-herbivore toxins, which negatively influenced caterpillar growth. The beneficial fungus gained sugars from the plant, while the plant gained soil nutrients from the fungus, such as phosphorus and nitrogen. Due to the plant-fungus symbiosis, plants were able to produce more toxins than normal due to the fungus’ acquisition of additional usable resources from the soil, and in turn harm the larvae's consumption of leaf matter. The effectiveness of this plant response was tested on several species of Lepidoptera. Adults Adults primarily consume solely floral nectar, and do not have a noticeable specialty. Life cycle A. caja hatches at the end of summer (from August to September), overwinters once, reemerges in spring, and finishes growth by June. From July to August (or September in warmer climates) the adults are active, primarily at night. Eggs are laid on leaf surfaces and the larvae hatch and feed shortly after the previous generation has died. After feeding for a few months, the larvae go into dormancy while covered in ground matter. In spring, the larvae resume feeding and pupate. By June or July, adults emerge, all from the same generation that was laid in the previous fall. It is key to note that during all life stages there is no generation overlap, either as adults or larvae. Caterpillars The caterpillars of this species are, like many caterpillars of the tiger moth family, “fuzzy” in appearance, leading them to be called "woolly bears" by casual observers. Once the caterpillars reach a certain size, they acquire hollow tubes that often contain irritating compounds. The larvae depend upon the host plant for their toxic compounds, which they convert from plant defense compounds to larval and adult protection compounds. The caterpillars can grow to a maximum size of 6 cm (2.4 in) long. Adults Adults are active from June to September (or August in more northern climates) predominately at night. They have red hairs