Pollinator Insects Other than Bees and Butterflies

by Rausa McManus, EMGV

We’re all familiar with bees and butterflies as the helpful pollen transferring insects that keep our vegetables producing, our flowers in bloom, and support plant growth in natural settings. While these are the most common pollinators, there are many other insects that are also beneficial pollinators. Among these are  wasps, ants, flies, midges, mosquitos, moths and beetles. Let’s take a look at how they operate.

Though wasps are not as effective as their bee relatives, they do play a role in this important task. The most famous of the pollinator wasps are the fig wasps. Specifically, they pollinate the mini-flowers which bloom inside the pear-shaped pod that eventually matures into the fruit. These fig wasps are so important in the fertilization process that wild figs would most likely disappear without them. They are also crucial to a species of orchid called Epipactus helleborine. Interestingly, this orchid emits a chemical with the odor of a caterpillar infestation, therefore attracting the wasps to their flowers.

A sphecid wasp is foraging on a bottlebrush flower (Caallistemon sp.) Photo credit: Justin Ballew, https://hgic.clemson.edu/factsheet/native-pollinators/

Ants, a fairly uncommon pollinator, have two methods of spreading pollen. As they walk between flowers, they facilitate pollination. Though not very efficient, this does help with a small number of plants. In North Carolina, worker ants diligently walk pollen grains between the flowers of elf orpine (Diamorpha smallii) a tiny plant that lives on granite and Sandstone outcrops. Though they are hard workers, ants can also harm the pollen they carry with an antibiotic they produce called myrmicacin. This antibiotic may reduce the pollen’s viability, making the ants’ work even less effective.

Flies, especially hoverflies or the family Syrphidae, are also called flower flies because of their unique attraction to blooming plants. There are approximately 6,000 species in this family alone that are known pollinators. They use their proboscis, or extended mouthpart, to reach the nectar of elongated flowers.

Another added benefit is that most hoverflies have predatory larvae. Hoverflies lay their eggs on plants near aphid colonies; the maggots travel through the aphid colonies and devour them. If you look closely at any plant with a lot of aphids present, you may likely also see hoverfly maggots, providing a natural pesticide to the plants they visit. Their most important role is in that of fruit crop pollination, including apples, pears, cherries, plums, apricots, peaches, strawberries, raspberries and blackberries. Though not the only family of pollinating flies, hoverflies are the rock stars of the pollinator flies.

Larva and adult photo credit: https://entomology.ces.ncsu.edu/2015/06/hoverflies-bee-mimics-provide pollination-and-biocontrol-services.

Without the next family of flies, the world would be void of chocolate treats. Let’s take a look at midges, the type of fly that is primarily responsible for the spread of cacao pollen, therefore absolutely crucial in chocolate production. Midges are the only known pollinators attracted to the flowers of the cacao tree, therefore enabling the cacao to bear fruit.  Due to their miniature size, midges can get into the tiny cacao flowers. They also coordinate their efforts with the flowers’ biorhythms by entering the blossoms at night while they are fully open. Thank you, midges!

The otherwise pesky mosquitos, known for their Dracula-like habit on humans and other animals, are also big fans of nectar. Female mosquitos who are laying eggs prefer to feast on blood, but the males drink the sweet nectar of flowers for energy to swarm in search of the mates. Though they most commonly pollinate orchids, they are known to help with other plants as well.

Though butterflies are lovely and garner a lot of attention in our gardens, their counterparts, the moths, also make a contribution. Curiously, they frequent white, fragrant flowers such as jasmine. Perhaps this is because they are creatures of the night and attracted to the light color. There are many moth varieties that populate the garden such as the hawk, sphinx, owlet, underwing and geometry moths. One that is also common is the hummingbird moth (Hemaris sp.)which imitates the action of a hummingbird. Another variety, the yucca moth (Tegeticula sp.), has a fascinating symbiotic relationship with the yucca. After the female deposits her eggs inside the flower, the moth transfers pollen from the flower’s pollen chamber to the stigma chamber, enabling the flower to make seeds. This is in perfect timing with the hatching of the moth’s hatching, which feed on the seeds the mother moth made possible by her actions.

Beetles are the last group of pollinators we will examine and among the oldest ones known. About 150 million years ago, at least 50 million years before bees existed, beetles were carrying on the work of pollination. They still hold that same job title today. Through uncovering fossils, there is evidence beetles originally pollinated cycads. Today they still pollinate descendants of cycads, mostly magnolias, lilies and other fragrant blossoms. Unfortunately, though, beetles do not have the same table manners as other sipping pollinators. They chew and and eat the plants they pollinate and leave messy residue as evidence. Some of the beetle families native to the Piedmont are weevils (Curculionidae sp.), sap beetles (Nitidulidae sp.), and the tumbling flower beetle (Mordella sp.).

A native leaf beetle (Chrysomelidae sp.), busy pollinating a sunflower (Helianthus sp.) photo credit: Justin Ballew, https://hgic.clemson.edu/factsheet/native-pollinators/

So, bees and butterflies, as important as they are as pollinators, have a lot of help from a variety of other insects.

Resources & Further Reading
Watts, Sue. “Plants for Pollinators.” The Garden’s Gate, www.clemson.edu, September-December 2019.

Yong, Ed. “Orchid lures in pollinating wasps with promise of fresh meat.” Discover Magazine, May 12, 2008.

Hadley, Debbie. “7 Insect Pollinators that Aren’t Bees or Butterflies.” ThoughtCo., July 20, 2019.

Ballew, Justin. “Native Pollinators”. Home and Garden Information Center, www.clemson.edu., January 19, 2018. https://hgic.clemson.edu/factsheet/native-pollinators/

https://www.fs.fed.us/wildflowers/pollinators/animals/beetles.shtml

https://entomology.ces.ncsu.edu/2015/06/hoverflies-bee-mimics-provide pollination-and-biocontrol-services.

Learn With Us, week of September 15

Downsizing Your Garden
Tuesday, September 17⋅7:00 – 8:30pm

Sarah P. Duke Gardens
420 Anderson St, Durham, NC 27708
with Deborah Pilkington, owner (retired) The Mini
Gardener, LLC, Duke Gardens Volunteer, and
Master Gardener
Your grand, spacious garden is a joy – until it is not.
Downsizing is simply an opportunity to re-examine and be
creative in your garden. Learn tips and techniques from
Deborah to re-cast your garden so it requires less time.

The Durham Garden Forum is an informal group that
meets once a month to enrich our gardening
knowledge and skill.
Tuesdays, 7:00- 8:30 pm at Sarah P. Duke Gardens.
Lectures free for members,
$10 general public.
No pre-registration necessary.

Cool Season Vegetables
Thursday, September 19⋅7:00 – 9:00pm

Sarah P. Duke Gardens
420 Anderson St, Durham, NC 27708
A remarkable variety of tasty vegetables (including root crops and greens) can be happy and healthy when the temperature drops and your tomatoes and squash are all but memories. It’s also the time to plant crops that will rejuvenate your soil over Winter as well as those that can be harvested early next summer. We will also be offering tips on what to do with your garden when it is too cold to get out there.

Getting Back to Basics

September is synonymous with school. So, this week we are getting back to basics with a post that defines foundational gardening terms. The better you understand these terms and phrases, the easier it will be to identify, select and care for plants in your landscape.

Growing season:  The period between the beginning of growth in the spring and the cessation of growth in the fall.

Hardiness zone:  Expressed as a number and letter combination from 1a to 13b, the US Department of Agriculture has assigned a zone to every geographic area of the United States based on the average annual minimum winter temperature. Tags on plants sold commercially often identify the zone(s) in which the plant will grow.   

Microclimate. Climate affected by landscape, structures, or other unique factors in a particular immediate area.

N-P-K:  Acronym for the three major plant nutrients contained in manure, compost, and fertilizers. N stands for nitrogen, P for phosphorus, and K for potassium.

Coreopsis major, blooming along roadsides now, is a native perennial hardy in zones 5a to 9b. It attracts butterflies and songbirds and is deer resistant. The flowers are large (for coreopsis) and the stems are tall. Photo by A. Laine

Annual: Plants started from seed that grow, mature, flower, produce seed, and die in the same growing season.

Biennial: Plants that take two years, or a part of two years, to complete their life cycle. By freely reseeding, a biennial plant may seem to come back year after year, but you are actually seeing new plants.

Perennial: A plant that lives more than two years and produces new foliage, flowers, and seeds each growing season. Tender perennial:  A perennial that is not tolerant of frost and cold temperatures. Applying a winter mulch can help it survive It may die off above ground and regrow from the roots.

Woody perennial: A plant that goes dormant in winter and begins growth in spring from above-ground stems. Herbaceous perennial: A plant that dies back in the winter and regrows from the crown in spring.

Exotic: A plant of foreign origin or character; not native; introduced from abroad, but not fully naturalized.  Naturalize: The process whereby plants spread and fill in naturally.

Native plant: A plant indigenous to a specific habitat or area. Nativar: A plant that is a cultivar of a native plant. Cultivar: A cultivated variety of a species. Propagation of cultivars results in little or no genetic change in the offspring, which preserves desirable characteristics.

Integrated pest management. A method of managing pests that combines cultural, biological, mechanical, and chemical controls, while taking into account the impact of control methods on the environment.

Invasive. Growing vigorously and outcompeting other plants in the same area; difficult to control.

Noxious weed. Weeds that have been declared by law to be a species having the potential to cause injury to public health, crops, livestock, land, or other property. Noxious weeds are very invasive. There are 124 plants in NC that meet the legal criteria.

When a gardening term has you stumped, refer to the glossary chapter of the Master Gardeners Handbook for a definition – there are hundreds of entries — and a small dose of continuing education.

— A. Laine

Resources & Further Reading

Glossary Chapter of Master Gardener Handbook: https://content.ces.ncsu.edu/extension-gardener-handbook/glossary

Find your plant hardiness zone:  https://planthardiness.ars.usda.gov/
USDA Plant Hardiness Zone Map, 2012. Agricultural Research Service, U.S. Department of Agriculture.

Noxious weeds in NC: https://plants.usda.gov/java/noxious?rptType=State&statefips=37

https://plants.ces.ncsu.edu/plants/coreopsis-major/

Learn With Us, week of September 8

Compost and Soil
Saturday, September 14⋅10:00 – 11:00am
Durham Garden Center, 4536 Hillsborough Rd, Durham, NC 27705
COMPOST & SOIL: The science, the mystery, the magic.
This talk will address local soil issues and how such challenges can be overcome with information gleaned from soil testing as well as proper and timely amendments. The basics of successful composting and vermicomposting will offer tips on how to transform food scraps, leaves, clippings and other organic materials into a nutrient-rich soil conditioner that will benefit your lawn and gardens. Simple composting practices and procedures available to all will also be covered.

Free/Registration required

Contact: 919-384-7526 or http://www.durhamgardencenternc.com

Sign up at the store, online or by phone
Include the seminar title and full name(s) of persons attending

September: To Do in the Garden

by Gary Crispell, EMG

Well, here it is … September! Some of y’all have been waiting for this since last October. For many, it is the beginning of your favorite time of the year—warm days, cool nights, lower humidity, winding down the summer garden … hurricanes. Enough contemplation! There is still much gardening to do this month. Let’s get to it.

Fertilizing
With the exceptions noted under “Lawn Care,” you can take your fertilizer and stick it in an air tight container and put it away until Spring.

Pruning
NOPE!  Fuggeddaboutit. If you must exercise your pruning tools go remove underbrush or unwanted saplings or something. Stay away from your landscape plants.

Spraying
Stuff to look for and where to look for it:  Wooly adelgid on Hemlock, spider mites on other coniferous evergreens, lace bugs on Azalea and Pyracantha and tea scale on Euonymus and Camellia.

A note about Lace Bugs. They will be active all year anytime the leaf surfaces are warm enough (e.g. about 40 degrees). Being diligent now will help keep them at bay after you have cleaned and put away your sprayer. Also, Azaleas planted in sunny places will have more lace bug issues than those planted in shade.

Spray Peach trees and Nectarine trees for Peach Tree Borers.

Maintain your rose program.

Be watchful in your Fall garden. Many insects and diseases are more active in the Autumn; They like this weather, too.

Weeds to be controlled this month:  Trumpet Creeper, Bermuda Grass and Blackberry.

Only spray if necessary.  Spray as little as possible. ALWAYS READ THE LABLE!

Lawn Care
September is the best time to seed and/or reseed a Tall Fescue lawn. Loosen the soil in bare areas and cover any areas larger than one square foot with wheat straw.

Apply lime and fertilizer as recommended on your FREE SOIL TEST.

Do not fertilize warm season grasses (e.g. Bermuda, Centipede, Zoysia). Fertilizing them now is like giving sugar to your kids at bedtime. They get real active much to their (and your) detriment.

If you missed the August window to treat your lawn for grubs, it is still open until the middle of September.  After that the little buggers quit feeding and go to sleep for the winter.

Propagation
You may dig and divide spring flowering bulbs now. Daffodils will be especially appreciative of this activity and will show it in the Spring.

Other Stuff to Keep You Outdoors on Gorgeous Autumn Days
Mulch shrub and flower beds.

Clean up and put away sprayers and other gardening equipment that won’t be used again until Spring.

Get your houseplants ready to come back inside. Break it to them gently by bringing them in for a little while each day. Be sure to rid them of insect pests before they come in for good.

If you do not have a fall garden, (What do you mean you don’t have a fall garden?!?) then it is time to chop, burn or toss dead vegetable plants. Burn or toss, especially if they had disease or insect issues.

Checkout the local garden center for spring flowering bulbs you can’t live without (or just covet a whole lot).  October and November will be the time to plant them. You know, “Shop early for the best selection.”

Find a good trail and take a hike. Take your kids or grandkids to the park. Read a book on the deck or patio. Get out of the house with any excuse you can come up with.

See ya’ in October for leaf season.