How many weeks does Range Caterpillar take to attain full size?

• A. Roughly 12 weeks to attain full size
• B. 4 weeks
• C. 24 weeks
• D. 48 weeks

Answer: (A)

The main idea is how long the larval stage of the range caterpillar lasts from hatching to reaching full size. Caterpillars grow by molting several times, and under typical rangeland conditions this growth phase takes about three months. So from the moment the eggs hatch to when the caterpillar is fully grown, you’re looking at roughly 12 weeks. After that, it pupates and becomes a moth. Shorter durations (like four weeks) wouldn’t allow for the necessary molts, while much longer times (24 or 48 weeks) exceed the usual larval period observed in the field.