Beyond Honeybees. Mike Andruczyk with Sandra McDonald

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1 Beyond Honeybees Mike Andruczyk with Sandra McDonald Mike Andruczyk is currently a Virginia Tech Extension Agent. He has worked as curator at the Norfolk Botanical Garden and is past president of the Colonial Virginia Chapter of the Holly Society. Sandra McDonald and Mike worked together to document the information he presented at the 2012 HSA Annual Meeting in Richmond, Virginia. Due to space constraints we were unable to include the entire document and accompanying photographs so I edited the version that appeared in Volume 31, #1 of the Holly Society Journal. This it the entire document, with photographs, submitted by the authors. Emily Jernigan, Editor Pollination can be achieved by many mechanisms besides wind and water depending on the morphology of the flower. Bats, birds, bees, beetles, butterflies, moths, wasps, and other insects can be pollinators. ANTS Ants love nectar and crawl to flowers to obtain nectar, but are not very good at cross-pollinating flowers. They visit low-growing flowers that are close to the stem. They do not need nectar guides. Some tropical plants have nectar outside the flowers to attract ants and rely on the defensive character of the ants. Plants from wet tropics to dry deserts have extrafloral nectaries. Five ant species have been observed on dwarf mistletoe. Winged male ants pollinate several species of orchids. BEES There are over 4,000 species of native bees in the United States. They include bumblebees, metallicgreen sweat bees, squash bees, and nonnative honeybees that pollinate many plants. Bees visit flowers to collect pollen and nectar for food for themselves and their young. Bees visit flowers with a lot of nectar and that are brightly or UV colored; however, they cannot see red so rarely visit those flowers. Bees also prefer sweetly aromatic or minty blossoms with landing platforms that are open during the day. Often these flowers are bilaterally symmetrical, flat, or tubular with nectar at the base of tubes. Flowers with nectar guides, and limited, sometimes sticky and scented pollen are other attractants for bees. The orchard mason bee, Osmia lignaria, collects pollen and makes it into a ball to put into a nesting tube where she lays an egg on each one. These bees nest in hollow stems, woodpecker drillings, and insect holes. They do not connect or share nests or protect each other. Some plants they visit are dandelion, Oregon grape, cherries and apples. These bees are not harmful since they do not drill holes in wood, but use holes that other insects or birds have made. The blueberry bee, Osmia ribifloris, is an effective pollinator of commercial blueberries. There are many species of leaf cutter bees which are important pollinators in North America, 63 of which are in Florida. They use cut leaves to construct nests in cavities, mostly in rotting wood. They create multiple cells in their nest, each with a single larva and pollen ball stored for the larvae to eat. They are important pollinators of wildflowers, fruits, vegetables and other crops. They use the leaves of almost any broadleaf deciduous plant to construct their nests. Some even use petals and resin along with leaves. The most commonly reported problem of leaf cutting comes from ornamental plants such as roses, azaleas, ash, redbud, bougainvillea, and other plants with smooth leaves. The carder bee, Arthidium manicatum, is a colorful, solitary bee introduced from Britain. The male bees drive away other insects to attract females. They are particularly good at pollinating alfalfa. Females supposedly use hairs or wool from plants to line their burrows.

2 Species of carpenter bees are in the genus Xylocopa. Carpenter bees excavate precisely rounded galleries inside wood, sometimes damaging structural timber. They are good pollinators for eggplant, tomatoes and other vegetables, flowers, and prairie wildflowers. Sometimes when the large carpenter bees cannot enter a flower they become nectar robbers by using their mouthparts to cut a slit at the base of the corolla and steal nectar without having pollinated the flower. Miner/polyester bees generally nest in the ground, often in paths or lawns, and some of the lawn nesting species nest communally. Miner comes from their nesting in the soil, and polyester from the lining of their underground nests with a polyester secretion. Their burrows are often marked by a small mound of soil. They cement the grains of sand together. There are several genera of miner bees. They are good pollinators for fruit trees and alfalfa. Bees in the genus Eucerini pollinate many prairie wildflowers, and plants in the Asteraceae family that includes asters, daisies and sunflowers. Cuckoo bees are from the three tribes Epeolini, Melectini, and Nomadini. They are brood parasites on other miner bees in the Anthrophoridae family. Some Nomadini also parasitize the nests of Andrenid been. The name cuckoo bee came from their habit of laying their eggs in the nests of other bees, reminiscent of the behavior of cuckoo birds. They lack pollen collecting structures (scopa) and do not construct their own nests. When the cuckoo bee larva hatches in the nest of the other bee, it eats the host larva. This cleptoparasitic behavior has independently evolved within the bees a number of times, with 16 lineages in the family Apidae, and 31 lineages parasitizing solitary hosts. Many cuckoo bees are closely related to their hosts and may bear similarities in appearance reflecting this relationship. Sweat bees are in the family Halictidae of the order Hymenoptera and seem to be anti-specialist. They are generalists, visiting a wide variety of flowers and rarely finding a flower whose pollen or nectar is unavailable. Bees in the genus Agapostemon are metallic-green. The downside for flowers these bees visit is that the more different kinds of flowers in bloom the bees visit on a foraging trip, the lower the chances of pollination. Sweat bees are attracted to the salts in human perspiration. They are small to medium sized and generally black or metallic colored, some being metallic green or brassy yellow. Bumblebees are in the genus Bombus and are common native bees and important pollinators in most areas of North America. They can be separated into three different classes based on the length of their proboscis (tongue) length: short, medium and long. The length of the tongue determines which kinds of flowers they visit. In spring the queens emerge from underground where they have spent the winter and look for a nest site, often underground in an old mouse nest or rodent burrow. Bumblebees visit flowers for both the nectar and the pollen upon which they feed. These resources are also used to feed the larval worker bees. After the first generation of workers hatches, the empty cocoons may be used for shortterm storage of nectar, but the bumblebees do not make and store large quantities of honey. Another reason bumblebees are important pollinators is their behavior of buzzing or sonicating flowers that require this behavior for pollination. Tomatoes and other flowers in that plant family don t produce nectar, but the bees visit them to collect pollen. They vibrate their wing muscles, making a buzzing noise, and shake pollen grains out of the anthers. Bumblebees are important pollinators. They especially like to visit large composite flowers and long tube-shaped flowers from various plant families and even fly on cloudy days. They are important pollinators for commercial raspberry and runner bean crops. There are two genera of squash bees: Peponapsis and Xenoglossa. They are solitary bees that pollinate squash, pumpkins, watermelons, and gourds and were the main pollinators of those plants before the Europeans introduced honeybees. Male bees dart between the flowers in the early morning and can be fast asleep in the withered flowers by noon. Squash bees are nonsocial, but sometimes gregarious ground-nesters.

3 Honeybees are in the genus Apis which currently has seven recognized species. These bees make honey and construct colonial nests out of wax. Honeybees, at least the Eastern type, appear to have originated in South and Southeast Asia. Eastern (Asia) species are kept in hives. Western (European or common) honeybees appear to have originated in eastern tropical Africa and spread from there to Northern Europe and eastward into Asia. There are many subspecies of honeybees that have adapted to various conditions. Dwarf honeybees are in the subgenus Micrapis. They make very small exposed nests in trees and shrubs and their stings are often incapable of penetrating human skin. Giant honeybees are in subgenus Megapis. There is one recognized species which usually builds single or a few exposed combs on high tree limbs, on cliffs, and sometimes on buildings. They can be fierce, and colonies are capable of stinging a human to death when provoked. Many of the flowers pollinated by bees have a region of low ultraviolet reflectance near the center of each petal which is invisible to humans. Bees can detect ultraviolet light and see the pattern called a nectar guide. WASPS Wasps are important pollinators and are in the same order, Hymenoptera, as bees and ants. Most wasps are in a group called Aculeata. Wasps are generally not covered with fuzzy hairs like bees and are therefore less efficient in pollinating flowers since it is less likely to stick to their bodies. They need pollen and nectar from a variety of flowers. True wasps have stingers that they use to capture insects or spiders for food for their larvae. Figs are keystone species in many tropical ecosystems. Fig wasps are responsible for pollinating the nearly 1,000 species of figs. Wasps are also useful for pest control as they capture caterpillars and spiders to feed their larvae. Yellow jackets are not very effective pollinators and seldom visit flowers except in the late fall. BEETLES Beetles comprise the largest set of pollinating animals due to sheer numbers. They pollinate 88% of the 240,000 flowering plants globally. Beetles were among the first pollinators to visit flowers and remain essential pollinators today. They pollinate ancient species such as magnolias and spicebush. They eat their way through petals and other floral parts. Fossil records show that beetles were abundant during the Mesozoic (about 200 million years before the present) and were visitors to the earliest angiosperms. Beetle-pollinated plants produce heat and the odor may mimic a food source. Flowers that beetles pollinate are usually large and bowl-shaped with sexual organs exposed, white to dull white or green in color, not strongly fruity or fetid in odor, open during the day, moderate nectar producers, have large, solitary flowers or clusters of small flowers such as goldenrods, spireas, have abundant pollen, and have no nectar guides. BUTTERFLIES Butterflies are very active during the day and visit a variety of wild flowers. They are less efficient than bees at moving pollen between plants since they do not pick up much pollen. They probe for pollen and favor clustered flowers that have a good landing platform. Preferred flowers are brightly colored (red, yellow, orange, purple); are open during the day; are ample nectar producers with nectar deeply hidden; have nectar guides; are narrow tubular with spurred flowers; only faintly fragrant; and have limited pollen. Butterflies are different from bees in that they can see red.

4 FLIES Two-winged insects (flies, gnats, mosquitoes) comprise a very large group. Many of them such as syrphid flies or flower flies specifically visit flowers. They are not as hairy as bees or as efficient in carrying pollen, but some are good pollinators. Some flies look like bees and wasps, but they can be distinguished by close examination. The flies have only one pair of wings while bees and wasps have two pairs of wings. Flies and beetles have been implicated as the primary pollinators of the earliest flowering plants. Some of these were also visited by bees and thrips, but pollination by birds, butterflies, moths and bats appeared only in more recently evolved plant families. Food is probably the major reward that flies obtain from visiting flowers. Flower-visiting flies have sensory structures on their antennae that allow them to detect floral scents. They usually have large eyes with color vision and can detect the glint of nectar in an open flower. At least seventy-one families of Diptera contain flower-loving species and flies are pollinators of or visitors to more than eleven hundred species. Flowers attractive to flies are mostly pale and dull to dark brown or purple; sometimes flecked with translucent patches; have a putrid odor like rotting meat, carrion, dung, humus, sap, and blood; do not have nectar guides; have little or no nectar and modest pollen; and flowers are funnel-like or complex traps. Bee flies have hairy bodies and long slender legs. Their proboscis is adapted for feeding on flower nectar. They collect nectar from dandelions in early spring. Blow flies, especially the blue bottle and green bottle, lay their eggs almost exclusively in dead or rotting flesh. They are usually the first insects attracted to a fresh carcass, sometimes within minutes of death. The eggs are most often laid around natural body orifices or open wounds, and the larvae molt and pupate at predictable rates for any given temperature and humidity condition making them important in forensic pathology. Dance flies are small flies found around wooded creeks during the spring. Some of the species are balloon-makers, the male flies capture an insect and enclose it in a frothy bag, then carries this package around with him as a lure to entice the female to mate. Larvae are usually found in rich, moist soil. The larvae of all empidids have been found in decaying vegetable matter and in aquatic associations of under the bard of trees. They are often seen in swarms under trees and around small streams where they wheel around in their mating flights. Some flowers that attract them are currants, stone-fruits, Mahonia, salmonberries, and wild lily of the valley. Flower-loving flies are found in sandy, arid, and semiarid habitats. They hover over bare patches of ground and can emit a loud hum. Despite the name, most of them never visit flowers. The adults are only active for a few weeks each year and feed on flowers in August and September. Syrphid flies look like bees, but have only two wings instead of four. They are very colorful and conspicuous insects. There are nearly 900 species in North America, most having yellow and black stripes, mimicking bees or wasps. Tachinid flies are the largest and most important group of insect parasitic flies with over 1300 species in North America. All species are parasitic in the larval stage, with many being important natural enemies of major pests. Some have been introduced for that purpose. They somewhat resemble house flies and are usually grey, black or striped, and often have many distinct abdominal bristles. Most tachinids attack caterpillars and adult and larval beetles. Others kill sawfly larvae, some types of true bugs, grasshoppers, or other types of insects. They suppress many important pests in the north central states. Some tachinid females lay mature eggs on caterpillars and they immediately hatch and start eating the caterpillar.

5 A large number of species of midges are natural enemies of other crop pests. The larvae of these species are predaceous with the most common prey being whiteflies and thrips. The larvae are tiny. Midges pollinate the flowers of the tropical cocoa tree. The flowers grow along the trunk and lowest branches of the trees. They are small and white and face down which allows the midges to pollinate them. Mosquitoes pollinate one species of orchid, Habernaria obtusata, the bog orchid. MOTHS Moths are attracted to flowers in clusters or which provide landing platforms; are white or dull colors of pink, red or purple; open late afternoon or night; are strongly sweet scented often only at night; have ample nectar with nectar deeply hidden like morning glory, tobacco, yucca, and gardenia; have no nectar guides; have limited pollen supply; or have tubular flowers without a lip. Some moths are also active by day. Their caterpillars, tobacco and tomato hornworms are well-known to gardeners as voracious feeders. The yucca plant is dependent upon the yucca moth for its survival. The female yucca moth gathers pollen from the flower anthers, forms it into a ball and stuffs it onto the stigma of the various flowers she visits. This is necessary for the flower to develop into the fruit or pod with seeds. The female moth inserts her ovipositor to lay an egg in one or more of the six chambers. Both the yucca and yucca moth benefit in the relationship. The hawk or sphynx moths are the world s largest moths and have the longest tongues of any other moth or butterfly. Some are up to 14 inches long. They pollinate Datura and many species of orchids and petunias while sucking the nectar. GARDENING FOR POLLINATORS Use a wide variety of plants that bloom from early spring into late fall. Plant in clumps rather than single plants. Use plants native to your region. Night-blooming plants will attract moths and bats. Avoid modern hybrid flowers, especially those with double flowers. Eliminate pesticides whenever possible. Use the least toxic ones available when you must use them. Read the labels carefully before purchasing because many pesticides are toxic to bees. Follow the label. Spray at night when bees and other pollinators are not active. Include several larval host plants in your landscape. Butterfly caterpillars will eat your plants so put those plants where you can tolerate the leaf damage. Create a damp salt lick for butterflies and bees. You can use a dripping hose and put a little sea salt or wood ashes in the mud. Leave occasional dead limbs or trees for nesting sites for native bees. Be sure these are not a safety hazard for people walking below. Use a hummingbird feeder to provide artificial nectar of one part table sugar to four parts water. Clean the feeder with hot, soapy water at least twice a week to keep it free of mold. Butterflies need resources other than nectar. They are attracted to some unsavory things and rotting fruit. Put slices of overripe bananas, oranges and other fruits or a sponge in a dish of lightly sea salted water and see which butterflies come. Sea salt has a broader range of micronutrients than regular table salt. Get some guide books and learn more about pollinators. The Bloom time list of pollen and nectar bee plants is at

6 Seed Blend Sample to Attract Pollinators 40% phacelia (Phacelia tanacetifolia) 3% red radish (Raphanus sativus) 25% buckwheat (Fagopyrum esculentum) 3% cornflower (Centaurea cyanus) 7% white mustard (Sinapis alba) 3% mallow (Malva sylvestris) 6% coriander (Coriandrum sativum) 2% anethum (Anethum graveolens) 5% calendula (Calendula officinalis) 1% borage (Borago officinalis) 5% black cumin (Nigella sativa) Bloom Date Chart Alsike Clover (Trifolium hybridum) Apr 4 Aster (Aster spp.) Sep 30 Basswood, Linden (Tilia spp.) Jun 20 Black Gum (Nyssa sylvatica) Apr 27 Black Locust (Robinia pseudoacacia) Apr 27 Blackberry (Rubus spp.) Mar 1 Crimson Clover (Trifolium incarnatum) Apr 10 Dandelion (Taraxacum officinale) Mar 5 Gallberry (Ilex glabra & coriacea) Mar 5 Goldenrod (Solidago spp.) Aug 1 Heartsease, Smartweed (Polygonum spp.) Jul 4 Holly (Ilex spp.) Apr 24 Huckleberry (Gaylussacia spp.) Apr 5 Ladino Clover, White Clover (Trifolium repens) Apr 14 Pepperbush (Clethra alnifolia) Aug 1 Persimmon (Diospyros virginiana) May 20 Privet (Ligustrum spp.) May 8 Raspberry (Rubus spp.) Apr 20 Red Maple (Acer rubrum) Jan 20 Sourwood (Oxydendrum arboreum) Jun 1 Sugar Maple (Acer saccharum) Feb 25 Sumac (Rhus spp.) Apr 1 Sweet Clover (Melilotus spp.) May 28 Tulip Poplar (Liriodendron tulipifera) Apr 17 Tupelo Gum (Nyssa aquatica) Apr 20 Vetch (Vicia spp.) Apr 28