Other Pollinators — Wasps
Wasps are very important pollinators. They often frequent flowers in search of nectar or insect prey.
They are considered generalist pollinators, and passively transfer pollen while feeding on nectar.
Wasps do not garner much notoriety as pollinators and are often overshadowed by their bee cousins.
Still there are those occasions where wasps are more valuable and efficient pollinators than bees.
Additionally, among wasp species are some of the most unique and fascinating pollinators, who
sometimes share an intimate relationship with their favorite plants.
Wasps are an important flower visitors and often frequent flowers in search of nectar and insect
Some wasps are considered generalist pollinators, and passively transfer pollen while feeding
on nectar from various plants. While doing so, they often overlap with other pollinators, such as bees, flies
or butterflies. However, because they generally lack abundant body hairs and do not feed on pollen, they
are considered less efficient pollinators than their bee relatives.
Some behave more frequently as nectar thieves than as true pollinators, especially when they pierce
the base of flowers to access the nectar without contacting the plant’s reproductive organs. This said,
despite not having the reputation of bees, wasps can and do effectively contribute to pollination.
In some plant systems and environments, they can become the most efficient pollinator, surpassing bees.
For example, in a study involving pollinators and the plant Schinus terebinthifolius, some social wasp
pollinators were more abundant and species-rich than bee visitors. Another study found that in some
environments, the western yellowjacket was a more effective pollinator than the honey bee. In that
investigation, it was observed that pollen of the plant Scrophularia californica was more efficiently
transferred by Vespula wasps and bumble bees than by honey bees, which visited the plant but did not
The vast majority of wasps are carnivorous. However, these wasps cannot survive based on a completely
meat-diet. Wasps need to supplement their diets with sugar and water, which very often comes from flower
nectar, or honeydew produced by insect herbivores.
Similar to bees, wasps have high energy requirements, and pollen and nectar allow them to acquire extra
energy to use for their high metabolisms. For this same reason, it is not uncommon to observe wasps feeding
The Pollen Wasp sting when disturbed and their stingers stay lodged in their bodies. Unlike bees and
yellow jackets they don’t leave their stinger behind so they are able to sting several times in a row.
The Pollen Wasp is not considered to be aggressive and this is evidence by the fact that they rarely
sting. But if they sting, it is a painful one.
Some gardeners don’t like Pollen Wasps since they destroy flowers as they look for nectar. The Pollen
Wasp also destroys ripened fruits and so in many instances they are eliminated. However, Pollen Wasps are
predators of many insects, especially crop eating insects and so can be beneficial to gardeners and
The Pollen Wasp constructs their nests with mud or rather dig burrow in the ground. Just like other wasps,
the female Pollen Wasp is the one responsible for constructing the nests. Usually their nests are built
in concealed places especially under the rocks and crevices. But Pollen Wasps build their nests in open
places especially on twigs of the trees. In these nests they are multiple individual cells where eggs are laid.
Pollen and crops are carried to the nest as they continue to provision the cells. In fact they partition their
cells using pollen and nectar. After that, the Pollen Wasp laid her eggs and then covered up the nests. Unlike
other wasps that feed their larvae with caterpillars, pollen wasps feed theirs with pollen and nectar.
The Pollen Wasp mostly get their nectar from flowers. The Pollen Wasp has a tendency of visiting
certain flowers for this purpose. The females are most commonly seen in June, though males emerge
later in the year. The Pollen Wasp tend to visit the flowers that females have already visited.
Generalist flowers that attract wasps have specific floral traits, such as dull coloration, unusual odor,
and readily accessible (exposed) and concentrated nectar. Most wasp can see UV light, and tend to
visit white- or yellow-colored flowers.
The majority of wasps have very short mouthparts or tongues, and as such, can obtain nectar only
from shallow flowers. Wasp-pollinated flowers can produce either large or small amounts of nectar.
Sweet fennel is an herb with a sweet licorice or anise scent. Small yellow flowers bloom in clusters that
attract bees, butterflies and wasps to the garden in the summer. Fennel grows in full sun and thrives
in zones 4 to 9. This herb can sometimes reach a height of 6 feet. In cooking, fennel is used to flavor
stews, roasts or in place of onion. It's a common ingredient in Mediterranean dishes.
This flower is named for the delicate white flower heads that resemble lace. Also known as wild carrot,
Queen Anne's lace is related to the common cultivated carrot, and the large tap root is edible, but the
leaves can cause skin irritation. Queen Anne's lace grows to 4 feet tall and can be found all over the
United States, growing wild in ditches or dry fields. The flowers bloom from early spring into the fall
and can often be seen with buzzing bees and insects, including wasps, which feed on other insects.
Growing to 36 inches tall, yarrow is a perennial with large clusters of flowers that bloom in shades of
yellow, pink or white. Yarrow is a tough plant, growing from zones 3 to 10 in full sun. It's drought
resistant and quite invasive if left alone. The leaves and flowers of yarrow are aromatic. Yarrow has
been used for medicinal purposes for centuries as an antiseptic or to fight against colds and purify
Wasps are attracted to the spearmint plant because of the myriad of other insects attracted to this plant's
fuzzy white flower. Spearmint is an herb that is quite invasive, spreading quickly over moist soil. It can
be found in most parts of America. The leaves can be dried and used for a refreshing tea, added to
salads or used as a garnish. Mint jelly is often made from this plant. Spearmint is also used as a treatment
for wasp stings.
Please Help Native Pollinators
Ask the Wisconsin Dept of Transportation to replace the planting of non-native grasses
with pollinator-friendly native plants along Wisconsin roadways. Provide a corridor for
Bees, Butterflies and Birds to move through the State and restore the natural beauty of
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