Caterpillars are immature moths or butterflies that are still in the larva stage. There are 180,000 different species. Not many are completely brown, but quite a few have brown markings or are various shades of tan, tawny or blackish brown. Most of these caterpillars are herbivores and eat a diet of vegetation. Under some circumstances, such as if they are denied access to vegetation, caterpillars will become cannibalistic and feed on their own or other species of caterpillars. The eating preferences of some common types of brown caterpillars are listed here.
Tiger Moth Caterpillars
Tiger moth caterpillars have earned the nickname woolly bears because of their puffy coat of fuzzy hair. They come in many shades and combinations of brown, black, tawny and yellow. They will devour just about anything green. They are often found on low lying plants, such as grass, flowers and weeds. According to Greg Stack, extension educator on horticulture from the University of Illinois extension, violets and lambs quarters are woolly bears' plants of choice.
Saddleback caterpillars are plump, brown or tan caterpillars with a green design on their back that looks like a saddle. They have hairy, stinging horns on both ends of their bodies, making it appear as if they are double-headed. Saddlebacks eat leaves off a wide range of trees and shrubs. Dogwood, elm, maple, oak, and fruit trees are common targets.
Puss caterpillars have a slug-like shape and are covered in downy hair that hides poisonous spines. They are often light brown, but can also be light or dark grey. They live primarily on trees, but also eat garden plants. Oak, elm and citrus trees are some of their favourites.
Spiny oakworms are tawny brown, while pin-stripped oakworms are greenish brown. As they name suggests, they target oaks, but are also commonly found in walnut trees.
Tent worms are slender, brown and black striped caterpillars that build tent-like nests in trees. Large numbers of caterpillars inhabit each nest and a single tree can be infested with numerous nests, making them destructive pests. Tent worms will consume almost any type of foliage, but fruit trees are their preference.