Pollinators

Our Pollinator Garden

In our pollinator garden, we focus on planting appropriate and diverse native plants, providing water, and using pesticides carefully (if at all) to attract, support, and protect native pollinators. Native plants have naturally adapted to grow well in the areas where they are found and often have a specialized relationship with the pollinators that are also native to that area. Although some plants rely on wind or water, almost 90% of plant species require the help of pollinators, such as bees, butterflies, moths, flies, beetles, hummingbirds, and bats, to help set seed and produce fruit. In return for their efforts, pollinators receive food, warmth, migratory sites, and shelter for mating, nesting, laying eggs, and overwintering. Unfortunately, improper use of pesticides, destruction of habitats, and even the invasion of non-native plant species that take the place of native vegetation can dangerously impact our native pollinators.

Some of the native plants in our Pollinator Garden include:

Bee Balm (Monarda fistulosa and Monarda punctata)
Blue Star (Amsonia hubrichtii)
Blue Wild Indigo (Baptisia australis)
Blueberry (Vaccinium spp.)
Butterfly Weed (Asclepias tuberosa)
Compass Plant (Silphium lanciniatum)
Field Pussytoes (Antennaria neglecta)
Fothergilla (Fothergilla gardenia)
Ironweed (Vernonia glauca)
Lanceleaf Loosestrife (Lysimachia lanceolata)
Mountain Mint (Pycnanthemum muticum)

Pinnate Prairie Coneflower (Ratibida pinnata)
Prairie Dock (Silphium terebinthinaceum)
Prairie Dropseed (Sporobolus heterolepis)
Rattlesnake Master (Eryngium yuccifolium)
Sedges (Carex spp.)
Shaggy Blazing Star (Liatris pilosa)
Sumac (Rhus copallina)
Sweet Pepper-bush (Clethra alnifolia)
Thoroughwort (Eupatorium hyssopifolium)
Viburnum (Viburnum dentatum)
Zigzag Goldenrod (Solidago flexicaulis)

 

Jump down to see a list of some of the native pollinators in our area

What is pollination, and why is it important?

As with many types of reproduction, it requires pollen grains (the “male” gamete) from one flower to fertilize the ovules (which produce the “female” gametes) inside other flowers of the same species. This forms a viable embryo, which grows, protected by the surrounding seed and encased in the developing fruit. If there is no fertilization, seeds and fruits do not form.

Depending on the structure of a plant’s flowers, there are various ways that pollen reaches the female stigma of a flower. In some cases (such as grasses and conifers) wind is a sufficient vector to carry the pollen grains to the awaiting flowers. In rare cases, such as for some aquatic plants, pollen is carried by water. In other cases, insects such as bees, butterflies, beetles, and flies visit flowers, collecting and feeding on pollen and nectar or even mating on the flowers. Pollen grains that stick to their legs, wings, and bodies are carried along and brushed onto the stigmas of other flowers they visit. Hummingbirds perform this same task, while sipping from flower to flower. This happens with many of the vegetables, annuals, and flowering plants in our gardens and landscape.

Without pollination, there would be no acorns, apples or squash produced, and seeds would not be produced to grow new zinnias and marigolds next year. Many animal and insect pollinators are now in decline. If we do our part to encourage them by providing appropriate habitats, they will reward us by making our habitats more productive and beautiful, too.

Important native pollinators

One of the first pollinators that may come to mind is the honey bee (Apis mellifera). Although swarms may occasionally move into hollow trees or other unintended spaces, most are managed by humans, kept in square beehives, where they live and from which honey can be harvested. Despite their wide use in the agricultural industry to perform pollination tasks, they are actually native to Europe—not North America! In fact, they are only one of more than 20,000 bee species in the world, 4,000 of which are native to the United States.

From small sweat bees to large carpenter bees, there are many different varieties that pollinate flowers in our

Unknown bee species on wild-growing Porcelain-berry (Ampelopsis brevipedunculata)

area. And that’s not including the many species of wasps, which are not actually “bees.” Although some native bees and wasps live in large, social colonies, many are solitary. Different species of both bees and wasps may live in ground nest holes, in compost or weedy areas, burrow into wood, or build paper nests or even “mud” tubes.
While many of these nesting structures rely on natural areas, other types of pollinators are even more dependent on specific plants. Many moths, butterflies, and beetles actually live and feed on specific plants. A common example is the Monarch Butterfly. It lays its eggs on native milkweed plants, and after they hatch, the caterpillar (larva) feeds on and often forms its chrysalis directly on the plant. Likewise, False Indigo (Baptisia) is the host for Wild Indigo Duskywing, Eastern Tailed-blue, and Orange Sulphur Butterflies. Turtlehead (Chelone lyonii) is a host for the Baltimore Checkerspot Butterfly, and Spice Bush (Lindera benzoin) is a host for the Spicebush Swallowtail.

Similar to butterfly chrysalides, moth cocoons are often formed on the undersides of leaves or twigs, in bark crevices, in the forks of branches, or even in leaf litter on the ground. Some moths are nocturnal, attracted to pale-colored flowers with heavy fragrance and ample supplies of nectar. Other moths, along with butterflies, visit flowers during the day.
Perhaps most surprisingly, however, is the oldest and largest group of pollinators world-wide: beetles! Some beetles have very old evolutionary links to the most ancient plant species, such as magnolias. Less common pollinators (not native to our area) are some species of bats, which feed on insects and nectar inside flowers. Most flower-visiting bats are found in Africa, Southeast Asia, the Pacific Islands, and Mexico. A couple of species do migrate north, into Arizona, New Mexico, and Texas, in the spring.

Jump down to see some pictures of native pollinators at Rutgers Gardens

Unusual Pollination

A lot of the common plants in our gardens and native landscapes have fairly straight-forward pollination procedures. But there are some wild examples in the plant kingdom that don’t fit the expected model! Here are a few to consider:

Beware frail insects! - The unique shape of Asclepias (milkweed) flowers includes grooves (“stigmatic slits”). Instead of individual pollen grains clinging to visiting insects, their legs or mouthparts slip through these slits, where entire sacs of pollen (“pollinia”) become attached and transferred to other flowers. Sometimes, weaker insects can become trapped this way and die with a leg caught in the flower!

Looks like lunch - Some plants, such as the native Pawpaw tree (Asimina triloba) and “Stinking Benjamin” Red

Pawpaw (Asimina triloba)

Trillium (Trillium erectum) have a unique method of attracting pollinators. The maroon-colored flowers of the pawpaw and red flowers of the trillium both emit a subtle unpleasant odor, reminiscent of rotting meat. Combined with the “meaty” colors of the flowers, they attract flies and beetles that normally feed on decomposing animal carcasses.

Smells like death - Taking the “dead” smell to a whole new level, the Corpse Flower or Titan Arum (Amorphophallus titanum), native to western Sumatra, and the Stinking Corpse Lily (Rafflesia arnoldii), native to south Asian countries, both emit a nauseating odor of decaying flesh. Among the largest flowers in the world (the Amorphophallus inflorescence can reach over 10 feet in height, while Rafflesia blooms can grow to over 3 feet across!), both are pollinated by carrion flies and carrion beetles. These plants are also thermogenic, which means they generate heat. It is thought that the heat aids in producing water vapor and dispersing chemicals, to help spread their pungent odor and attract more pollinators.

Fool me once… Orchids are a deceptive group, luring pollinators with all sorts of false promises. Those pollinated by hummingbirds and butterflies are brightly colored, often with yellow patterns that mimic the anthers and pollen of other plant species, enticing nectar-loving pollinators, but providing none of the nectar they expect! Orchids of the Ophrys genus have a lower lip (“labellum”) that mimics a female bee or wasp—down to the color, iridescence, markings, and even a scent that mimics the insect’s pheromones. Males of the species are attracted to the flowers, thinking they’ve found a potential mate. Some orchids in the Oncidium genus actually mimic territorial wasps or bees that are attacked by adversaries!

It’s what’s inside that counts - There is a special relationship between the fig wasp and the Caducous or Smyrna Fig (Ficus carica). A female fig wasp enters a small opening in an unripened fig. While laying eggs inside, where the male and female flowers reside, she performs important pollination duties. The male wasps hatch first and mate with the female wasps that are still enclosed in galls. The males then chew a small hole out of the fruit, through which the females exit after they hatch. Now covered with pollen from inside the developing fruit, the females fly off to another fig tree, to lay their eggs and continue the pollination cycle. The abandoned fruit continues to mature, until it is ripe for eating.

Look out, it’s a trap! - The Victoria or Giant Waterlily (Victoria amazonica) has quite an elaborate song and dance. The day before blooming, a bud rises out of the water. It opens, glowing white, in the darkening twilight on the first day in its bloom cycle, radiating warmth and emitting a strong fragrance. Scarab beetles, carrying pollen, arrive to feed on the nectar. As they crawl around, the pollen from their feet and abdomen pollinates the flower. When morning approaches, the flower closes, trapping the nocturnal beetles inside. During the day, the pollen-producing stamens open. By the time the flower (now pink or purple!) opens on the second night, the beetles are covered with pollen, which they carry off to a new first-night blooming flower in the receptive female stage. The next morning, the pollinated flower closes and sinks back into the water to ripen.

Common Native Pollinators

Following is a list of a few of the common types of native pollinators you are likely to see in this area:

BUTTERFLIES
American Lady Butterfly (Vanessa virginiensis)
Baltimore Checkerspot Butterfly (Euphydryas phaeton)
Black Swallowtail Butterfly (Papilio polyxenes)
Cabbage White Butterfly (Pieris rapae)
Clouded Sulphur Butterfly (Colias philodice)
Common Buckeye Butterfly (Junonia coeni)
Eastern Tailed-blue Butterfly (Cupido comyntas)
Eastern Tiger Swallowtail Butterfly (Papilio glaucus)
Fiery Skipper Butterfly (Hylephila phyleus)
Monarch Butterfly (Danaus plexippus)
Mourning Cloak Butterfly (Nymphalis antiopa)
Orange Sulphur Butterfly (Colias eurytheme)
Painted Lady Butterfly (Vanessa Cardui)
Question Mark Butterfly (Polygonia interrogationis)
Red Admiral Butterfly (Vanessa atalanta)
Silver-spotted Skipper Butterfly (Epargyreus clarus)
Spicebush Swallowtail Butterfly (Papilio troilus)
Wild Indigo Duskywing Butterfly (Erynnis baptisiae)

MOTHS
Geometer Moths, Inchworms (Geometridae family)
Hummingbird Moth (Hemaris diffinis)
Owlet Moths (Noctuidae family)
Underwing Moths (Catocala species)

BEES
Bumblebees (Bombus species)
Carpenter Bees (Xylocopa species)
Leafcutter Bees (Megachile species)
Miner Bee (Andrena cornelli)
Squash Bees (Peponapis species)
Sweat Bees (Agapostemon, Halictus, and Lasioglossum species)
Wandering Cuckoo Bees (Nomada species)

WASPS
Great Black Wasp (Sphex pensylvanicus)
Pollen Wasps (Pseudomasaris species)
Scoliid Wasp (Scolia dubia)

BEETLES
Blister Beetles (Meloidae family)
Checkered Beetles (Cleridae family)
Locust Borer (Megacyllene robiniea)
Sap Beetles (Nitidulidae family)
Soft-wing Flower Beetles (Melyridae family)
Soldier Beetles (Cantheridae family)
Tumbling Flower Beetles (Mordellidae family)

OTHER
Hoverflies, Flower Flies (Syrphidae family)
Ruby-Throated Hummingbird (Archilochus colubris)



 

Some Photos of Native Pollinators in Rutgers Gardens

beetle Eastern Tiger Swallowtail Bumble Bee Black Wasp
Carpenter bee (Xylocopa species) on
Salvia farinacea, native

Eastern Tiger Swallowtail (Papilio glaucus) female on Rudbeckia hirta, native

Bumblebee (Bombus species) on Echinacea, native

Great Black Wasp (Sphex pensylvanicus) on Tropical Milkweed (Asclepias curassavica), South America

Locust Borer Wasp

Snowberry Clearwing or Hummingbird Moth (Hemaris diffinis) on Verbena bonariensis, South America

Locust Borer (Megacyllene robiniea) on Hydrangea paniculata, China & Japan

Giant Swallowtail (Papilio cresphontes) on Bee Balm (Monarda fistulosa), native

Scoliid Wasp (Scolia dubia) on Mountain Mint (Pycnanthemum), native