Why Pollinators and Flies?

Syrphid fly on Potentilla/shrubby cinquefoil

This past week was National Pollinator week and in the spirit of that, I presented a talk on pollinators to a garden club in Cedaredge, CO.  When I found out the presentation was outside and that their garden was mostly done blooming, thoughts of how am I going to present crossed my mind.  Having many acres of gardens at our Mesa County Extension office, I came up with the idea of I would buy blooming plants and work them into my talk.  Come visit our gardens if you get to Grand Junction.  

Hoverfly aka Syrphid fly on Apache Plume, Bob Hammon

At the last minute, shhhh none of us Extension Agents are last minute, I ran out to purchase blooming perennials that would later be planted in our gardens.

My talk cover why would we want to install a pollinator garden; well that answer is simple.  The more me build and get rid of the native plants, the more we hurt the ecosystem and the pollinators.  So instead of lawn that you only mow, why not make at least a portion a garden for the natives.  As a reminder, pollinators just like other animals need shelter, food resource for young and old, water, and space.  Research what kind of pollinators you want to attract as many like different things.  For example, some pollinators like bees like a saucer of water with rocks to land so they can sip the water.  Hummingbirds like a shallow water source or a “shower” and butterflies like mud puddles.  Some pollinators like butterflies need places to get out of the wind.  And don’t forget food for the young larvae as well as pollen and nectar for the adults.  Did you know too that hummingbirds also eat sap and insects?  They are not solely dependent on nectar.  And yet other solitary bees need bare soil to create their nests.  These are the reasons I say you need to research what you need to provide in your garden.

Syrphid fly larvae, TRA

As I was giving my talk, with the blooming perennials in front of me, the flowers were being visited by a small orange butterfly, some sweat bees and one of my favorites the syrphid fly.  That’s right I said FLY.  Not all flies are pesky like the house fly. Dictionary.com defines a Syrphid fly as “any of numerous beelike or wasp-like flies of the family Syrphidae that feed on the nectar and pollen of flowers and have larvae that feed on decaying vegetation or prey on aphids”.  Hey, anything that eats aphids can’t be half bad.  These insects are very important pollinators of a wide range of plants.  While teaching native plants at the Black Canyon of the Gunnison this year, we saw the Wood’s rose was very well visited by bees, bumblebees and syrphid flies.  A common name of these syrphid flies is flower flies.  Maybe that sounds more attractive.

Syrphid fly on bindweed, Bob Hammon

Many syrphid flies, Syrphus sp. imitate bees using strips so predators think they have a stinger, which they don’t.  I like that they are like little hover crafts, hovering over flowers before they land.  At my office, we have a patch of yarrow that was blooming in November, and there was the pollinator, still eating.  They are different from bees with big eyes, short, stubby and bristly antennae, and they only have one pair of wings.  They are not equipped to carry pollen like bees.

Flowers they are attracted to are flowers with an umbel inflorescence or composite flowers such as yarrow, asters and native thistle. Other flowers include native onions, roses, Rubus (like raspberry), and hawthorn (last 3 in the rose family), willow, and many more.  Hoverflies are active from early spring to fall so it is important to provide flowers throughout the season.  And remember the larvae eat aphids, what a bonus.

Syrphid fly and honey bee, Bob Hammon, retired CSUE TRA Entomologist

By Susan Carter

CSU Extension Tri River Area Horticulture and Natural Resource Agent

 

Resources: https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/flower_flies.shtml

The Xerces Society

https://www2.ipm.ucanr.edu/natural-enemies/syrphids/