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Spicebush swallowtail caterpillar

These are my favorite caterpillars and I like finding them in the backyard. The first sign is when I find a leaf on my native Kentucky spicebush (Lindera benzoin) cut and folded like this.

Spicebush leaf with spicebush swallowtail caterpillar

When I open the leaf, I usually see a small spicebush swallowtail caterpillar (Papilio troilus).

Small spicebush swallowtail caterpillar

In a week or so, I often find a large leaf folded in half like this.

Spicebush leaf folded in half by spicebush swallowtail caterpillar

When I open the leaf, this is my special treat.

Close-up of spicebush swallowtail caterpillar with eyespots

Isn’t it a cutie? Those are false eye spots and the head is actually hidden under what looks like a mouth, but isn’t. The face is supposed to look scary – especially to critters looking for a meal.

The folded leaf is created by a web spun by the caterpillar. It hides there in the daytime and comes out at night to eat.

Spicebush swallowtail butterfly (Papilio troilus)

Eventually, the caterpillar changes into a chrysalis and emerges as a spicebush swallowtail butterfly. These butterflies only lay their eggs on spicebush or sassafras (Sassafras albidum) plants.

Spicebush is one of my favorite native Kentucky shrubs. I appreciate the small yellow blooms that are one of the first signs of spring, and I like the delightful spicy smell of the leaves. And, it’s the host of my favorite caterpillar!

Spicebush is blooming

Spicebush (Lindera benzoin) blooms are the latest sign of spring in the backyard. In my opinion, this is a first-rate shrub for suburban landscapes. This native Kentucky plant is easy to grow and does well in shade or sun.

It has small yellow flowers in early spring and attractive foliage in summer, and female plants have bright red berries in early autumn. The leaves have a pleasant spicy smell when crushed. It can grow up to 15 ft. high but it can be kept to most any size by pruning.

a native Kentucky shrub that's great for landscaping
1. flowering spicebush 2. close-up of flower 3. summer foliage 4. autumn leaves 5. late summer berries on a female plant

And if that isn’t enough, it’s also the major host plant for spicebush butterflies (Papilio troilus). I wrote about the spicebush caterpillar last summer and these images review the butterfly’s life cycle.

Papilio troilus life cycle
1. folded leaf covering small caterpillar 2. small caterpillar 3. full-grown caterpillar 4. chrysalis 5. spicebush swallowtail butterfly

Last summer I found several caterpillars on my two spicebush shrubs and saw the butterflies in the backyard. I’m not sure which I enjoyed more.

Spicebush is fairly common as an understory shrub in our Kentucky woods. Their yellow bloom makes them easy to spot this time of year. I’m glad to find them in the woods and I hope to see more of them in suburban yards.