Category: Butterflies

The Eastern Tiger Swallowtail butterfly (Papilio glaucus) is a prevalent and stunning butterfly found in the eastern regions of North America. Its range extends from Ontario down to the Gulf Coast and northern Mexico, east of the Rocky Mountains. These butterflies are active from spring to fall, often soaring above deciduous forests, woodlands, and streams. They are also commonly seen in residential gardens, parks, and orchards.

Characteristics

Tiger Swallowtails boast an impressive wingspan of up to 6 inches (15 cm), ranking them among the largest butterflies in North America. Their hindwings feature long, pointed tail extensions, which give them their characteristic swallowtail appearance.

The color of the eastern tiger swallowtail can vary. Males are yellow or yellow-orange with black tiger stripes. Their wings are bordered in black with yellow spots, and they have black “tiger stripes” running across the top of their wings. Their long black tails have blue patches on them.

Females come in two forms. The yellow form resembles the male but has additional blue shading on the hindwings. The black form is called dimorphic coloration, which adds a level of protection by mimicking the distasteful Pipevine Swallowtail. These females often exhibit a shadow of the “tiger” stripes.

Host and Nectar Plants

The Eastern Tiger Swallowtail utilizes a large variety of host plants, mostly trees, such as cottonwood, ash, birch, wild black cherry, tulip tree, sweet bay (magnolia), and willow.Adult Eastern Tiger Swallowtails feed on nectar from flowers. Their long proboscis allows them to access nectar deep within the flowers. They are attracted to a wide variety of flowers, including native milkweeds, phlox, lilac, ironweed, Joe Pye weed, Gayfeather, tall verbena, Mexican sunflowers, pentas, purple coneflowers, and zinnias.

Behavior

Tiger Swallowtails are solitary, preferring to spend most of their life in the canopy of deciduous trees. Recently hatched larvae spend their days resting in a silken hammock attached to a leaf. At night they will begin feeding on their host plant.

Males will form large groups is when they participate in a behavior called puddling, in which they congregate on mud, damp gravel or puddles. They extract sodium ions and amino acids from these sources which aid in reproduction. Females will occasionally puddle, but do not form congregations. Adults have also been seen feeding on dung, carrion, and urine.

Lifecycle

Egg Stage: Female eastern tiger swallowtail butterflies lay their greenish eggs singly on the upper surface their host plants. Each female can lay up to 250 eggs. The eggs are small, round, and greenish yellow.

Caterpillar Stage: After about a week, the eggs hatch into tiny caterpillars. Initially, the caterpillars are brown and white, resembling bird droppings, which helps protect them from predators. As they grow, they turn bright green with two large, false eyespots on their thorax, which can startle predators.

Like all swallowtails, the caterpillar of Papilio glaucus possesses an osmeterium, an orange, fleshy organ that emits foul-smelling odor repel predators. Normally hidden, the osmeterium is located on the first segment of the thorax and can be everted when the caterpillar feels threatened. The combination of eyespots and osmeterium makes the caterpillar resemble a snake.

Chrysalis Stage: The chrysalises can range from beige to dark brown to green which helps it to blend in the environment and protect it from predators. The larvae that experience the shortening days of late summer will enter diapause after transforming into pupae. The pupae stop developing throughout the winter and wait for increasing day length and warmer temperatures. They produce glycerol and trehalose, which act like antifreeze to protect them from freezing. These pupae emerge as the first eastern swallowtails you see in the spring.

Adult Stage: The adult butterfly has a lifespan of 2 weeks.

Once considered a single butterfly with a vast range, there are four other distinct species of tiger swallowtails:

Western Tiger Swallowtail (Papilio rutulus)

Two-tailed Swallowtail (Papilio multicadata)

Canadian Tiger Swallowtail (Papilio canadensis)

Appalachian Tiger Swallowtail (Papilio appalachiensis)

The tiger swallowtail butterfly is not considered to be a threatened or endangered species. However, as with many other butterfly species, their populations may be declining due to habitat loss and other human activities. It is important to protect and preserve their habitats to maintain healthy populations of tiger swallowtail butterflies. Click here to learn how to create a butterfly garden that will attract these majestic butterflies.

The eastern tiger swallowtail is the state butterfly of Alabama, Delaware, Georgia, North Carolina and South Carolina, and is the state insect of Virginia.

Native plants offer several benefits, making them a great choice for landscaping and gardening. Choose native plants that thrive in your specific region. They’re adapted to local ecosystems, which means they’ll require less water, fertilizer, and maintenance.

Pollinator populations have declined significantly in recent years, mainly due to habitat loss. Homeowners can help by creating pollinator-friendly gardens. Here are some of the best native pollinator plants to include in your yard.

Aster (Symphyotrichum spp.)

This North American native with cheerful daisy-like flowers provides a food source for many pollinators at a time of year when other food sources are scarce. Endangered monarch butterflies feed on the nectar in preparation for their journey south.
Zones: 3-10, depending on variety
Exposure: Full sun to partial shade
Height/Spread: 1 to 6 feet tall, 1 to 4 feet wide
Bloom time: Summer to fall

Blazing Star (Liatris spp.)

This native has flowers spikes that provide nectar and pollen for a wide range of bees, butterflies and beneficial moths. The larvae of liatris flower moth feed on the flowers and seeds, while liatris borer moth larvae eat the stems.
Zones: 3-9, depending on variety
Exposure: Full sun
Height/Spread: 1 to 5 feet tall, 6 inches to 2 feet wide
Bloom time: Summer to fall.

Bee Balm (Monarda spp.)

Whorls of red, purple, pink, or white tubular flowers provide a steady source of food for bees, butterflies, and hummingbirds.
Zones: 3-9
Exposure: Full sun to partial shade
Height/Spread: 1 to 4 feet tall, 1 to 3 feet wide
Bloom time: Late spring to fall

Black-eyed Susan (Rudbeckia spp.)

Rudbeckia has a prolonged bloom time that attracts butterflies and other pollinators. The late season seed heads attract finches and other birds. It is a larval host plant to Wavy-lined Emerald (Synchlora aerata) and to Silvery Checkerspot (Chlosyne nycteis) butterflies. It is an important nectar plant for fall-migrating monarch butterflies.
Zones: 3-9, depending on variety
Exposure: Full sun to partial shade
Height/Spread: 1 to 3 feet tall, 1 to 3 feet wide
Bloom time: Late spring to fall

Blanketflower ( Gaillardia spp.)

Famous for its cheerful color and extended bloom time, draw nectar-loving bees and insects, while their seeds attract granivorous birds like sparrows and finches.
Zones: 3-9, depending on variety
Exposure: Full sun
Height/Spread: 24-30 inches , 24 inches wide
Bloom time: Mid-summer to fall

C0lumbine (Aquilegia spp.)

Hawkmoths and bees are attracted to this native and migratory hummingbirds fuel up on the nectar during their journey north.
Zones: 3-9
Exposure: Full sun to partial shade
Height/Spread: 8 to 36 inches tall, 8 to 24 inches wide
Bloom time: Mid-spring to early summer

Coneflower (Echinacea spp.)

This native with cone-shaped flowers in an array of colors is one of the best summer bloomers for supporting a wide range of pollinators. Butterflies including monarchs, fritillaries, swallowtails, and painted ladies feed on the sweet nectar.
Zones: 3-9
Exposure: Full sun
Height/Spread: 1 to 5 feet tall, 1 to 2 feet wide
Bloom time: Summer

Goldenrod (Solidago spp.)

Goldenrod is an essential native plant with yellow flower plumes that support late season pollinators such as native bees, bumble bees, honey bees, butterflies, beetles, flies, moths, and wasps.
Zones: 3-8, with some to Zone 9
Exposure: Full sun to partial shade
Height/Spread: 1 to 7 feet tall, 1 to 6 feet wide
Bloom time: Late summer to fall

Hyssop (Agastache spp.)

The lavender nectar-rich flowers are highly attractive for butterflies, bees and hummingbirds.
Zones: 3-10, depending on variety
Exposure: Full sun
Height/Spread: 3 to 8 feet tall, 1 to 3 feet wide
Bloom time: Mid-summer to fall

Ironweed (Vernonia spp.)

Ironweed is a magnet for butterflies and is listed by the Xerces Society as having special value to native bees. Ironweed is the larval host plants for  the Ironweed Borer moth.
Zones: 3-10, depending on variety
Exposure: Full sun
Height/Spread: 2 to 8 feet tall, 3 to 5 feet wide
Bloom time: Mid-summer to fall

Joe Pye-weed (Eutrochium spp.)

The showy flowers of this native plant are an essential late season food source for hummingbirds, bumble bees, honey bees, wasps, and butterflies such as swallowtails, skippers, red admirals, and fritillaries. Migrating monarch butterflies feast on the nectar-rich flowers as they make their journey south.
Zones: 3-9, depending on variety
Exposure: Full sun to partial shade
Height/Spread: 3 to 8 feet tall, 1 to 5 feet wide
Bloom time: Mid-summer to fall

Milkweed (Asclepias spp.)

Milkweed is one of the most important pollinator-friendly plants and the sole food source for monarch butterfly larvae. The flower nectar, pollen, and leaves are food sources for a wide range of bees, wasps, hoverflies, beetles, butterflies, and moths.
Zones: 3-9, depending on variety
Exposure: Full sun
Height/Spread: 1 to 6 feet tall, 1 to 3 feet wide
Bloom time: Summer

Salvia  (Salvia spp.)

Salvia is a mint relative with nectar-rich flowers that appeal to a wide range of pollinators. The colorful tubular or open-faced flowers attract hummingbirds, butterflies, native bees, bumble bees, and honey bees.
Zones: 4-10, depending on variety
Exposure: Full sun
Height/Spread: 1 to 5 feet tall, 1 to 6 feet wide
Bloom time: Late winter to fall, depending on variety

Tickseed (Coreopsis spp.)

The cheerful disc-shaped flowers  provide a continuous source of nectar. Pollinating insects that feast on the flowers include carpenter bees, leaf cutter bees, long-horned bees, and sulphur butterflies.
Zones: 3-9
Exposure: Full sun
Height/Spread: 1 to 4 feet tall, 1 to 3 feet wide
Bloom time: Late spring to fall, depending on the variety

Verbena (Verbena spp.)

The nectar-rich flowers are a feast for the butterflies.
Zones: 3-9
Exposure: Full sun, partial shade
Height/Spread: 6-12 inches tall/ 12-36 in. wide
Bloom time: Spring-fall, depending on variety

Milkweed has a fascinating pollination mechanism that sets it apart from many other flowering plants! Milkweed flower clusters consist of multiple individual flowers that arise from the stems of a single branch.

Each individual flower consists of five petals that are fused to form a distinct shape, often described as resembling a star or a crown known as the corona. The corona contains specialized structures called hoods and horns. The hoods hold the nectar that attracts bees and butterflies and other pollinators.

Enclosed within the corona is a structure called the gynostegium, or stigmatic chamber. This reproductive chamber has 5 vertical slits called stigmatic slits around its perimeter. These slits allow access to the female ovaries and male pollinia within it.

Instead of being loose grains, as is typical of most flowers, the pollen in milkweed is packaged within sticky structures called pollinia  (singular: pollinium) which are masses of pollen grains that stick together and are located in the gynostegium.

When insects land on the hoods of the flowers to feed on nectar, their foot slips into the stigmatic slit. Inside the stigmatic slit, insects come in contact with the pollinia.  The stigmatic slit essentially “captures” the insect’s leg or foot, ensuring effective pollen transfer.

For pollination to occur:

1. An insect is attracted to the flower’s nectar and lands on one of the five hoods.
2. The insect’s leg or appendage slips into the  stigmatic slit (that acts like a trap door) between the hoods and touches the pollinia.
3. The insect pulls its leg out, bringing the pollinia with it.

   

4. The insect visits another milkweed flower and accidentally slides its leg into the slit again.
5. The insect extracts its leg, dislodging the pollinia, which is then transferred to the flower and completes pollination.

While this method ensures cross-pollination, it can be risky for insects. If their legs get snagged on the filament holding the sticky pollinia sacs, they may become trapped. Smaller bees are especially vulnerable and can perish inside the flowers.

The milkweed’s unique pollination mechanism benefits the plant in several ways:

• Cross-Pollination: By requiring pollinators to visit multiple flowers, milkweed promotes cross-pollination. This genetic diversity enhances the plant’s chances of adapting to changing environmental conditions.
• Reduced Self-Pollination: The pollinia attachment system prevents self-pollination. This ensures that the plant receives pollen from a different individual, preventing inbreeding and maintaining genetic diversity.
• Nectar Reward: Milkweed produces nectar as a reward for pollinators. In exchange for nectar, pollinators inadvertently transfer pollen between flowers, aiding in fertilization.
• Seed Production: Successful pollination leads to seed production. Milkweed seeds are equipped with silky hairs that allow them to disperse easily in the wind, increasing the plant’s chances of colonizing new areas.

Overall, this intricate pollination mechanism ensures milkweed’s survival and contributes to the health of its ecosystem.

Resources:
http://www.microscopy-uk.org.uk/mag/artfeb05/bjmilkweed.html
https://www.natureinstitute.org/article/craig-holdrege/the-story-of-an-organism-common-milkweed

Recommended Books for Further Reading

While spring is often considered the primary time for sowing seeds, there are still many seeds you can plant during the summer months. Planting seeds in summer for autumn blooms not only extends the colorful display in your garden but also provides nectar for butterflies and other pollinators.

Here are some fast-growing annuals that will bloom later in the season and into fall.

Zinnias (Zinnia elegans): These cold-hardy annuals will bloom until autumn’s first frost. Sow their seeds through the first week of July, and they’ll take about 60 to 70 days to flower. Zinnias are fast-growing, low-maintenance, and attract butterflies and hummingbirds with their colorful, nectar-rich blooms. Deadheading encourages more flowers to bloom.
Days to Germinate 5-24
Days to Bloom After Sowing 50-60 (7-8 weeks)

Sunflowers (Helianthus spp.): Sunflowers peak in the middle of summer but continue to bloom through part of fall. If planted in June, they can grow up to 12 feet by October. Sunflowers attract bees with their large, dark centers, which act as landing pads for pollinators.
Days to Germinate 14
Days to Bloom After Sowing 75-100 (10-14 weeks) Check for your variety.

Cosmos (Cosmos bipinnatus): Add this charming plant to the landscape and you will be rewarded with abundant butterflies. Creating a graceful visual impact in the garden, it is perfect for sunny borders or containers. Ideal addition to beds and borders, containers, cottage gardens, prairies and meadows. Excellent as cut flowers.
Days to Germinate 7-10
Days to Bloom After Sowing 70-84 (10-12 weeks)

Blue Bachelor’s Button (Centaurea cyanus): Also known as cornflowers, the silver foliage offsets its blue blooms tremendously and attracts other butterflies and many different beneficial insects. The flowers also attract birds, especially American goldfinches.
Days to Germinate 7-14
Days to Bloom After Sowing 65-75 (9-10 weeks)

Mexican Sunflowers (Tithonia rotundifolia) yield dozens of showy daisy-like blooms in fiery shades of red, orange, or yellow and brighten up any garden. The blooms attract a wide variety of bees, butterflies and hummingbirds, and can be used as cut flowers.
Days to Germinate 7-14
Days to Bloom After Sowing 80 (11 weeks)

Gomphrena (Gomphrena globosa), also called Globe Amaranth, is a great annual for summer color. It thrives in full sunlight, is drought tolerant and easy to grow. Butterflies and other small pollinators are drawn to these tiny flowers. Flowers are often dried at the end of the summer and used in dried arrangements because the flowers retain their good color.
Days to Germinate 7-14
Days to Bloom After Sowing 80 (11 weeks)

Cleome (Cleome Hassleriana) also known as Spider Flower, is a beautiful annual flower that can add height and drama to your summer garden. The blooms are a favorite nectar source for hummingbirds, butterflies, bees, and other insects.
Days to Germinate 7-14
Days to Bloom After Sowing 80 (11 weeks)

Cowpen Daisy (Verbesina encelioides) also known as Golden Crownbeard is a native annual with many branches covered with  yellow blooms which are a  favorite of bees and butterflies, but is ignored by deer.  Native range spans from California to Arizona, New Mexico to Texas, Utah, Colorado, Montana, east to Kansas.
Days to Germinate 7-14
Days to Bloom After Sowing 80 (11 weeks)

California Poppy (Eschscholzia californica)  is a native annual  famous for illuminating entire hillsides on the West coast, their bright orange blooms can be planted and enjoyed almost anywhere. Their bright orange petals serve as a beacon for butterflies, drawing them into your garden.
Days to Germinate 14-21
Days to Bloom After Sowing 60-75 (8-10 weeks)

Borage (Borago officinalis) also known as starflower, is an easy, fast-growing, annual herb with vivid blue flowers and the flavor and scent of cucumbers. While it is considered an herb, it’s often grown as a flowering plant to entice butterflies and other pollinators into vegetable gardens. It is also the host plant for the Painted Lady butterfly. In addition to being a great plant for pollinators, the flowers are edible and add a beautiful pop of color to salads or summer drinks.
Days to Germinate 7-14
Days to Bloom After Sowing 45 to 60 (6-8 weeks)

Here are some tips for planting wildflowers in late spring and summer:

1. Direct Sow: The trick to summer planting is to sow directly into the ground, containers, or raised beds.
2. Watering: Keep your seeds and soil well-watered for the first 4-6 weeks after planting. Do not let the soil dry out!
3. Sunlight and Drainage: Choose locations with at least six hours of direct sunlight each day. Avoid overly shaded areas, as they result in weak plants with sparse flowers.
4. Proper drainage is equally important for healthy blooms.

These summer flowers can brighten your garden with vibrant colors, attracting many butterflies and other pollinators and birds as well as adding beauty to the autumn landscape! Happy Gardening! 🌼🌿

Milkweed is the only plant that monarch butterflies will use as a host plant for their larvae. It is vital that we plant milkweeds that are native to our area to help the dwindling population of monarchs in North America. However, it requires care in handling.

Milkweed plants produce compounds known as cardenolides, also called cardiac glycosides. It is highly toxic substance found in milkweed sap which is toxic to animals. Its bitter taste warns away many of the animals and insects that try to eat milkweed leaves. Monarch larvae, however, are unaffected by the toxin, and they can sequester the cardenolides in their tissues. By feeding almost exclusively on milkweed leaves, the caterpillars accumulate enough of the cardenolides in their bodies to make them distasteful to predators. The toxic compounds stay with the caterpillars as they mature through subsequent stages of development, so they are toxic to predators both as larvae and as adult butterflies.

Humans are not exempt from this poison. Milkweed sap can be very dangerous if it gets in your eyes. This poison can cause corneal endothelial toxicity. This toxicity affects the innermost layer of the cornea and can cause symptoms such as blurred vision, light sensitivity and extreme pain. These symptoms often do not present immediately, which is why most patients and doctors never associate it with milkweed poisoning.

So, the next time you are working in the garden, remember these helpful Safety Precautions when handling milkweed:
• Wear gloves
• Avoid rubbing eyes or wiping sweat from brow
• Always wash hands  immediately after handling milkweed

Do not touch your face, nose, mouth and especially your forehead with milkweed sap on your hands. Even if your hands are dry the toxins from the sap remains on your skin until they are washed off. The sap can travel from your forehead into your eyes from the sweat on your forehead.

If you suspect that you may have milkweed poisoning, it is important that you seek medical help immediately.

You can find more information here:
https://butterflyfunfacts.wordpress.com/milkweed-sap-in-eyes/
https://www.reviewofoptometry.com/article/lepidoptometry