Caterpillar Setups > Semi-Closed Terrariums

High-humidity cages can spell doom for many species of butterflies whose caterpillars live in a relatively dry environment and can get sick. One major exception to this are the admirals and viceroys. They are accustomed to feeding in humid riparian areas (especially in the eastern U.S.). Raising admirals and viceroys in a terrarium with a glass lid makes sense because the caterpillars do NOT get sick in this environment (of course, you still need to change out plant and remove frass once a week) and willows and cottonwoods stay succulent in the high humidity.

The problem with not providing willows with high humidity is that they can dry up in less than an hour and freshly collected caterpillars can wander off! When you obtain willow cuttings, seek out relatively new growth; but cut out the terminal ends of branches with the newest growth. (Those can dry up anyway.) By exercising a little practice and patience with handling willow and cottonwood cuttings, you will find that it gets easier.