Ask the Expert! June 20-26

ask the expert

In celebration of Pollinator Week (June 20-26), we invited you to ask our panel of experts on any questions you had on insects and pollinator-friendly plants. Thank you for submitting your questions!!! ...We've got answers for you! 

We would also like to thank our expert panel for providing excellent responses! Our distinguished experts were:

  • Robert Currie, Entomologist, University of Manitoba
  • Linda Dietrick, Master Gardener
  • John Morgan, Prairie Ecologist, Biologist
  • Diana Bizecki Robson, Curator of Botany, Manitoba Museum
  • John Skinner, Skinner Native Seeds.


Here are the questions submitted by Manitobans and the answers provided by our experts. Click on each question to reveal their answer! 

I have had this flower come up every year but I'm not sure what it is. I think it is an Iris but not sure. Can you help identify this plant? (Picture below)

Iris ochroleuca Iris orientalis

It appears to be an iris of the species Iris orientalis, formerly known as Iris ochroleuca. It belongs to the Spuria class of irises, of which there are many garden cultivars, but I've never seen this species in local gardens or nurseries, so I think it must be pretty rare here. According to Wikipedia, it originates from Turkey and Greece. In the UK it's known as Turkish iris, while in the US it is usually called yellow banded iris. Apparently it is hardy to zone 4, which means it will overwinter here in a reasonably protected spot. Thanks for sharing the lovely photo! I should also mention that Manitoba has a wild iris, Iris versicolor or blue flag iris. It's an excellent garden plant that prefers a moist to wet site, as canoers of our lakes will know. Pollinators like bees and hummingbirds enjoy its blooms in early summer.

-Linda Dietrick, Master Gardener

I was weeding a pollinator garden in my neighbourhood which I planted last year. I noticed this "bug" on the New England Aster and wondered what it was. I was hoping it was a caterpillar but doesn't look like one. Can you take a look at this picture and help me identify this bug? (Picture below)
lady beetle larvae

The insect on your asters is a lady beetle larvae. This is the immature stage of the common insect known as a lady beetle or ladybug. It is a beneficial insect in that it is a predator and is particularly effective in keeping insects like aphids under control without the use of pesticides. The larvae will turn into an inactive resting stage called a pupae, then emerge as the familiar orange coloured lady beetle with a number of black spots that you are likely more familiar with. It is also a voracious predator of aphids and some other insects.

-Dr. Rob Currie, Entomologist, University of Manitoba

Today, I was in my garage and noticed this insect flying around. It is not very big, but wasn't sure the name of the butterfly/moth? Do you know what it is? (Picture below)
owlet moth

I think it is a species of owlet moth (Noctuidae) but I can’t say for sure which genus it is from based on the image. The University of Alberta has a good moth website moths that can be accessed here: 

-Diana Bizecki Robson, Curator of Botany, Manitoba Museum

If I want to naturalize my lawn to better host pollinators, what plants would work for a Wolseley Winnipeg yard? Is there an optimum process for doing this?

Native Manitoba grasses and wildflowers are best to host pollinators. Establishing them into an existing lawn is a multi-year process. Best to start small and consult native MB nurseries:

-John Morgan, Prairie Ecologist, Biologist

I have limited space and budget on my property but I want to maximize habitat in the space I have. What are the top 2 or 3 perennials, shrubs and trees for me to focus on?

Here are some of my favourites, but there are lots of good choices:

  • Trees - 1. Western Mountain Ash - smallish tree to 12', beautiful blooms for bees and fruit for birds. 2. American Basswood - Tilia Americana. Eventually will make a large tree, but has a nice form and bees love the flowers.
  • Shrubs - Potentilla fruticosa - Shrubby cinquefoil. Long bloom period and yellow flowers.
  • Perennials - Antennaria - Pussytoes. Will grow as part of the lawn. Early blooming for pollinators. Prairie Flax - Linum lewisii. Beautiful blue flowers. Relatively long bloom period early in the season. Purple prairie clover - Dalea purpurea. Late season, blooms for a long period and pollinators love it.

Of course, there are a lot of great choices - these are just some of my favourites!

-John Skinner, Skinner Native Seeds

How long should I wait in the spring before I “clean up” my garden? Is it ok to get a jump on spring cleaning and keep dead material in an open box?

Cut back your last year plants as late as you can, at least after this year's perennials are up and growing well. Use the old stems/leaves as a weed control mulch to conserve the overwintering pollinators hibernating in the previous year's stems.

-John Morgan, Prairie Ecologist, Biologist

Is it beneficial to keep a water basin / bird bath in the yard for pollinators? What do I need to consider so I don’t do more harm than good?

Bees like most creatures require water. While they can gain some moisture from sources like nectar or water condensed on plant surfaces, they often need to collect it. This is particularly true for the social species that may use it to help cool their nests. Some bees will collect and evaporate water in colonies as a form of "air conditioning". If bees are not provided with a source of water they may collect it from areas where they will become a nusiance such as water taps, swimming pools, or air conditioners. Putting a source of water out early in the season will help to provide for their needs and prevent them from "training" to other sources.

Water sources should provide a place for them to land without drowning (rocks or wooden floats for example). You also need to ensure you are not providing a breeeding site for mosquitoes. Inspecting the source for mosquito larvae and pupae should be done about every five days and water should be dumped and replaced if you find developing mosquitoes.

-Dr. Rob Currie, Entomologist, University of Manitoba

I have a wooden bee house with holes drilled into it. Last year I was thrilled to see all of them occupied but now I am not sure when and how to clean it out. Any suggestions?

Solitary bees utilize any sort of tunnel to construct cells, provision them with a mixture of pollen and nectar and deposit and egg on the pollen lump. In Manitoba, the egg usually hatches into a larvae that completes development to a prepupal stage (for many species) where it will overwinter and then continue development the following spring. You do not want to destroy these cells as they form the next generation of bees so any "nest cleaning" should not be done until they have all emerged.

If you have a nest that is empty and no longer harbours developing bees it can be cleaned with a pipe cleaner and treated with a 3 to 5% solution of bleach to control foliar molds and pathogens. If bees are already utilizing the nest the best approach may be to let it go for another season and then emerge bees into a container and release them the following spring.

-Dr. Rob Currie, Entomologist, University of Manitoba

I was weeding a particularly overgrown garden bed that had no flowers blooming yet and a whole bunch of bees started flying out of the greenery. I think they were ground nesting bees. Very exciting! So my question is about timing: what is the window I have between waiting for bees to emerge from their burrow, when I can start working the soil and when I should stop?

If bees are emerging from an overwintering site the soil can probably be worked to the extent needed in about mid May. If you have ground nesting bees they may be provisioning larvae in tunnels in the ground and tilling that section of soil would disrupt the population. If that patch of soil or lawn could be left undisturbed it would be best for the bees.

-Dr. Rob Currie, Entomologist, University of Manitoba

My pollinator garden is half in the sun and the other half is in shade, of course the plants on the sunny half are doing great but the shady side is struggling. Do you know of any native plants that would do well in shade?

Here is a list of native plants that are shade-loving: Wood columbine, Canada anemone, Canada violet, Meadow rue, Jewel weed, Fringed brome, Tall bluebells. Kelly at Prairie Originals has a more extensive list of shade-loving plants on her website - please visit

-John Skinner, Skinner Native Seeds

Why is it important for pollinators to have flowers blooming in succession throughout the season? Why is having a diversity of plants important in the garden?

Some pollinators are long-lived either as individuals or as colonies that build populations throughout the season (from spring to the first hard frost in fall). Most plants, in contrast, stay in bloom for comparatively short periods and thus a single species of flower will not provide enough support to keep many bees alive throughout the entire season. Other species of bees are specialists and have to synchronize thier emergence with a particular species (for example willow or sunflower). If those plants are not present the specialist bees will not be able to survive or have reduced success. Flower diversity (particularly with native species of plants) is very important to support the diverse range of rare but important specialists that inhabit our landscapes.

-Dr. Rob Currie, Entomologist, University of Manitoba

We are looking into building a bat house and a purple martin house on our acreage next year for mosquito and wasp control. Would these scare away the pollinators?

Great question! Bats are nocturnal and forage on a wide variety of insects such as mosquitoes and moths at night. Bees and many insect that we have in Manitoba forage almost exclusively during the day and so would not be affected by bat predation.

There are flowers that bloom in the evening, often white in colour with highly disected blossoms and they typically release a strong perfume odour in the evening to attract night flying insects such as moths. These moths would be a target for bats but enough moths would likely survive to satisfy the pollination requirements of plants.

Bats emit a radar and use it to detect and capture moths, but moths have evolved some fascinating defence capabilities. Some have radar detectors and take wild evasive manuvers to avoid caputure! It has also been recently discovered that some have radar jamming mechanisms (that operate by rubbing their genitals together and against their bodies) which is thought to reduce the effectiveness of the radar. In some areas of the world bats themselves act as pollinators and their is a pollination syndrome named after bat loving flowers called Chiropterophilly.

-Dr. Rob Currie, Entomologist, University of Manitoba