Category Archives: Insects

Advice, Insects, Shrubs & Trees, Websites

Insect Galls on Trees

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By Laura Gardner, Master Gardener in Training

I was out for a walk earlier this summer and noticed that a number of trees in my neighbourhood have lumps on their leaves, leaf stalks, shoots, or at the ends of their branches. At first glance you might be alarmed and think they are diseased, but many are the homes of tiny insects such as aphids, mites, sawflies, psyllids, and midges. They are often quite numerous and they come in different shapes and sizes. A gall is formed through the expansion of plant cells—similar to a tumour. This may be triggered by organisms such as viruses, bacteria, fungi, nematodes, or insects. Insects induce the galls through actions such as oviposition (inserting the egg into the plant tissue), the release of chemicals by the female and eggs, and through feeding. It is a shelter for the young and protects them from predators. While sometimes causing leaf deformity, in the majority of cases, galls are a cosmetic concern and do not harm the tree.

Here are a few you may encounter that are caused by insects:

These variable shaped galls specific to Populus deltoids (Eastern cottonwood) are the homes of an aphid called Mordwilkoja vagabunda (Poplar Vagabond Aphid). New galls are a light colour but become darker with age. Each gall releases upwards of 2,000-winged offspring in mid-July to early August. Sounds like it could have been the inspiration for a science fiction novel or movie.

Rabdophaga strobiloides (Willow Pinecone Gall Midge) are found at the ends of branches of various Salix spp. (Willow). What is amazing about these structures is that up to 31 different insects use them for their young—residing in the papery-like folds of the gall.[i] The galls are also frequently predated by birds and parasitic wasps.[ii] The biodiversity that Willows support is wide and for this they are known to be keystone species—they are also among the earliest plants to flower in the spring and support emerging pollinators like Queen Bumblebees.

Euura proxima (Willow Redgall Sawfly) frequents certain Salix spp. (Willow). This gall can be identified by its red bean-like appearance on the leaves. Sawfly larvae are often mistaken for Butterfly or Moth caterpillars. They can be distinguished by the number of abdominal prolegs: the former has six or more and the latter five or less.

Pachypsylla celtidismamma (Hackberry Nipple Gall Maker) is a Psyllid (Jumping Plant Lice) that forms round, often clustered galls on the underside of Celtis (Hackberry) trees. Adults spend the winter in cracks of the tree bark itself or even in nearby buildings.

The Eriophyid mite, Vasates quadripedes (Maple Bladder Gall) forms on Acer spp (Maple) such as the upper leaves of this Acer x freemanii ‘Autumn Blaze’ (Freeman Maple ‘Autumn Blaze’). The galls first appear as green, then turn to red, and finally black. The mites overwinter in the creases of the tree’s bark.

So, if your trees have strange growths on them, check out the wonderful web site https://gallformers.org. There you can identify galls by their specific host trees, the form of the galls, and their location on the trees. You can also narrow your search down to those that occur in Ontario. Another good site for identification is https://www.bugguide.net, a comprehensive database of insects for the US and Canada.

[i] Willow Pinecone Gall Midge. Minnesota Seasons. http://www.minnesotaseasons.com/Insects/willow_pinecone_gall_midge.html#:~:text=It%20consists%20of%20numerous%2C%20stunted,shape%20resembles%20a%20pine%20cone

[ii] Van Hezewijk, B.H. and Roland, J. (2003), Gall size determines the structure of the Rabdophaga strobiloides host–parasitoid community. Ecological Entomology, 28: 593-603. https://doi.org/10.1046/j.1365-2311.2003.00553.x

Bees & Pollinators, Butterflies and Moths, Insects, Slugs and Bugs

Holes in Leaves

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By Christine Freeburn, Master Gardener

Several years ago I heard a wonderful talk by Martin Galloway on “Holes in Leaves.” His philosophy was that you can never totally eradicate pests from your gardens, so you should enjoy the beautiful lacing they do to your leaves. At the time, I was skeptical about how I could love holes in leaves and the pests that put them there. However as a Master Gardener, I now understand his perspective and I do try for a balance using safe methods to control pests. Integrated Pest Management (IPM) is a practice where pests are controlled using environmentally safe and economically sound values. Biological controls like BTK or parasitic nematodes can be used. Barriers such as diatomaceous earth, wood ashes or sticky boards are mechanical control methods as well as hand picking. Cultural methods include plant nutrition, sanitation, planting pest resistant varieties and plant rotation (in the case of vegetables).

Although we don’t want bad bugs in our garden, we do want the beneficial bugs that are predators and parasites. These include dragonflies and damselflies, lady bugs, lacewings, spiders, wasps and some types of flies.

Aphids or plant lice are one of the most common pests to attack your plants. They are tiny soft bodied creatures that can be black, red or green in colour. They suck the sap from your leaves, and leave a sticky substance behind. You will often see them in a long line on your stems. Red aphids are common on garden phlox. You can use an insecticidal soap for aphids. Or use a blast of hose water to knock them off your plants.

Beetles are hard bodied insects that are generally easy to find on your plants. There are many types and they are often named after their plant of choice, like scarlet lily beetle. The most effective method for controlling beetles is hand picking. Look for the striped cucumber beetle inside the blossoms. When handpicking, place a hand under where the beetle is to catch it as they tend to jump when you touch them.

Caterpillars are another garden pest that are easily spotted. In spring you may find your Hydrangea arborescens has closed, puckered leaves which are holding the common leaftier. You can gently open the leaf and remove and destroy the caterpillar inside or pluck of the entire leaf and squish.

Slugs and snails are sometimes difficult to find as they like dark damp places and feed at night. But you will know you have them when they are munching on your hosta leaves. Check out Gardens Plus for Dawn’s formula for slugs.

As we enter the dog days of summer, we are all battling voracious bugs eating our beautiful flowers and vegetables. The healthier your plants are, the less they will suffer from a deluge of bad bugs. That is why it is important that you give your plants the water and nutrients they need to be their best. Good soil health and good fertilizing methods will give you healthier plants.

Remember that anything you apply to your plants to kill those pests can also hurt pollinators and will be on the vegetables and fruit that you ingest.

To make your garden less inviting to pests

  1. plant the right plant in the right spot to keep it happy and not stressed
  2. do not overcrowd plants which encourages dampness and pests
  3. diversity in your garden will help with pest control – if there are a variety of plants, specific pests will not take over
  4. keep nitrogen levels moderate as many pests like aphids thrive on plants with high levels of N.
  5. Remove garden litter; if pests are present as they can overwinter there.

My favourite method of hand picking beetles and slugs and hosing down aphids is no cost and gets you out into your gardens….where you can enjoy your own “Holes in Leaves.”

For more information on garden pests go to https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems.aspx

or try https://cdn.dal.ca/content/dam/dalhousie/pdf/agriculture/ExtendedLearning/gardenbox/Managing%20Vegetable%20Pests_Garden%20Box_Online.pdf

Bees & Pollinators, Birds, Butterflies and Moths, Garden Design, Information, Insects, Native Plants, Perennials, Shrubs & Trees, Sun Gardening, Vegetable Gardening

The Joy of Sharing our Gardens

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Reflections after a Garden Tour

by Emma Murphy, Master Gardener

It’s been a tough few years for all of us because of COVID-19, but I had time to reflect this weekend on why it’s been hard for me as a gardener. While it’s been wonderful to have our gardens as an oasis and source of comfort during the pandemic, I realized that other than a few close friends, no one had seen all the work (and the results) that my husband Grant and I had achieved over that time.

So it was with great anticipation that we looked forward to our Lakefield garden being featured on a garden tour organized as a fundraiser to celebrate 60 years of the Lakefield Horticultural Society.

While we spent a few very crazy days trying to put the final touches on our garden (my husband decided he would build a beautiful pergola [awesome] a week before the event [not so awesome] so plants had to be moved into pots and then back into the beds just a few days before) — sorry I digress — everything was perfect on the day — the weather was spectacular, we placed the last bits of mulch to cover a few empty patches and we looked forward to welcoming our guests.

The new pergola.

As the first people arrived (I think our first visitor was a man on a bicycle!) I began to realize how much I had missed the joy of sharing our gardens with others. And as the day progressed, it was wonderful to hear other people’s perceptions — for some it was inspiring, for some a bit overwhelming (we have a 3/4 acre property in a small village), for some they loved that we had plants they had never seen before (not your typical garden). Everyone seemed to leave with a smile on their face, which made our day.

Grant created numerous raised beds over the past few years — at my request — and we’ve had great success with them. We also purchased a “COVID present” for ourselves — a long wished-for greenhouse to extend our gardening season, and it’s been put to good use.

We’ve spent time over the past few years planting more native plants as I learn more about the benefits of creating habitat as well as having an aesthetically pleasing garden. Hey, it’s not all about me!! Doug Tallamy’s book is a great start to understanding the benefits we can provide in our humble gardens to the greater ecosystem.

There is definitely a balance — we’re aiming for a 50/50 balance of native/non-native — because I love my daylilies and peonies and don’t want to give them up (they give me pleasure), but I also love the hundreds of pollinators (bees, butterflies, wasps etc.) that flock to my Common Boneset (Eupatorium perfoliatum), Pearly Everlasting (Anaphalis margaritacea), Cup Plant (Silphium perfoliatum), and Cardinal Flower (Lobelia cardinalis) because I am choosing to plant native plants.

Boneset (white) and Cardinal Flower (red)

Last winter I grew some native (and non-native) plants using the Winter Sowing technique (because most native plant seed requires winter/cold stratification) and it was a great success (with some lessons learned – but that’s another blog).

Grant set up a Plant Sale area for the garden tour and people were able to buy plants that they saw in the garden (although alas, I did not take any cuttings on my amazing orange Butterfly Weed – a type of milkweed – which really caught everyone’s attention).

The Plant Sale area

Over the day I saw many gardening friends I hadn’t seen in several years, and made all sorts of new friends. It felt like my community was coming together — like we were reconnecting after a long time apart in a beautiful place. And I realized that gardening is both a solitary and a very social activity. We even got featured in the local newspaper.

We raised funds to support our local horticultural society, we got back to feeling ‘a bit normal’, and most importantly we got to reconnect with people over a common passion — the love of gardening.

I hope that all of you will find opportunities to reconnect with people this summer and share your gardens and plants and trade stories about attracting pollinators etc. with others. It’s a feeling like no other. #happygardening

Our lovely rudbeckia and greenhouse in the background.
Bees & Pollinators, Birds, Butterflies and Moths, Children, Dreams, Garden Design, Health, Insects, Perennials, Planting, Propagation, Seeds, Shrubs & Trees, Soil, Vegetable Gardening

Why Do We Garden?

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by Emma Murphy, Master Gardener

“To plant a garden is to believe in tomorrow.” Audrey Hepburn

If you’re like me, you love to garden. Time in my garden provides me with joy on so many levels — emotional, physical, social, creative — and connects me with the outdoors and the environment. And while the COVID-19 pandemic has turned our lives upside down, one of the silver linings is that we’ve seen a renewed interest in gardening and its benefits, whether you’re working in a large garden or a few containers on your balcony. So I thought I would explore some of the top reasons I think we garden.

Physical and Emotional Health

Gardening is physical. As a low to medium impact exercise that requires both strength and stretching, you’ll see increased muscle strength and cardiovascular fitness over time, as well as improved sleep and diet (if you grow your own produce). On the emotional side, gardening reduces stress, anxiety, and depression and improves self esteem.

It’s good for the mind — gardening calms me down and helps me be more patient with myself and those I interact with on a daily basis. It gives me time to contemplate as I go about my tasks, up to my elbows in soil. Even weeding is cathartic, pulling out those little terrors by the root!

Just visiting gardens helps to calm the mind, bringing a sense of contentment and tranquility from looking at beautiful landscapes, flowers, or just colour and texture.

Building Relationships

While gardening can be a solo activity (some of my favourite moments are just by myself in my green oasis), it’s also a fabulous way to connect with people, whether they be family or strangers!

Teaching people how to nurture a living thing and to be responsible for a little bit of the environment is a lesson and gift we can share with others. Gardening knowledge is shared through generations — I love hearing about plants handed down from grandparents, or children working with their parents to grow seeds for the first time. It’s a great way to pass on critical life lessons — about patience as plants and vegetables grow, responsibility as they look after their care, and loss when flowers die at the end of a season.

Beyond family, gardening helps us connect with the broader community. Whether you plant too many tomatoes or zucchinis and end up giving them away to neighbours, or participate in a community garden plot, gardening can be a very social activity and a chance to learn from, and share your bounty, with others.

Learning Life Values

Gardening teaches you important life values like patience, determination, caring, and hard work. It also makes you very humble as you realize that there is always something new to learn. You need to observe the seasons and the weather, and this puts you in contact with the natural world. I love that I can get dirty and do this very physical activity, working with seeds and plants and seeing growth in all I do.

Growing Your Own Food

Gardening provides benefits for your wallet, your nutrition, and reduces your environmental footprint. By growing your own food (either from seeds or small plants), your food is automatically more sustainable simply because you are doing it onsite or in a community garden. If you control the ‘inputs’ and do it well, you can save a lot of money.

But ultimately there is nothing more rewarding than planting and maintaining your own vegetable garden and harvesting (and sharing) your results. And we all know how much better homegrown produce tastes versus conventional produce at the grocery store. If you have too much produce, then you can just share the love with others!

Connecting With Nature

I think this is one of the best reasons why people have a garden — the sunshine on your face, hands in the dirt, and feeling connected to nature. The garden is so much more than just plants and flowers — it’s the birds, the bugs, the bees, the spiders, the snakes and all the small mammals. I feel like I am establishing a little ecosystem in my own garden and that I am trying to give back for all the benefits that I receive.

Working in the garden also gives you that sense of wonder, accomplishment, and reward. To grow plants is to give life. It keeps you busy but reminds you to be one with the earth. To see the results of something growing from seed to six feet tall is just incredible.

Exploring Creativity

I find gardening to be an incredibly creative activity. Finding the right plant for the right spot, mixing colours, and making sure there is interest for every season — these are real challenges. I’ve spent much of the past few years learning about new plants to consider in my garden, especially natives.

Helping The Environment

Finally, gardening is so important for our planet. Even though we create our gardens (so they are human made) they do represent natural environments, with trees and shrubs and plants that are all taking in carbon and releasing oxygen. The plant roots stabilize the soil and filter water, and the plants themselves support our pollinators.

We live in a symbiotic relationship with our gardens. We give back by planting and maintaining them, but we receive so much more from them than we give.

Why do you garden?

Houseplants, Insects, Slugs and Bugs, Websites

Quarantines are Not Just for Humans

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By Mary-Jane Pilgrim, Master Gardener

Seeing bugs outside is generally pretty tolerable as we know that many of them are pollinators, but seeing them inside our houses is a completely different story, right? Fortunately, it’s usually easy to manage most indoor pests with little more than some water, a cotton swab, and a soap solution. It all starts with a few preventative actions:

Aphids
  1. Whenever you happily bring home a new treasure (or sometimes, victim!), make sure that you carefully inspect them. Many types of houseplant bugs piggyback their way into your house from friend’s homes or stores. Look on leaf undersides, along the stems, and even in the soil for signs of common pests (sticky substances, flying cloud when disturbed, little bumps, fine silky webbing).
  2. Put your new treasure in solitary confinement for a few weeks, like in a spare room. Even if you think a new plant is pest-free, it may have pest eggs or larvae that you can’t yet see. Watch it carefully and only put it in close contact with other plants after it’s been confirmed to be pest-free. If the pandemic has taught us anything, quarantining is right at the top of the list and it applies to plants as well as humans.
  3. Place a few yellow sticky cards in among your plants. Many pest insects are attracted to the color yellow, and they’ll quickly get trapped on the card. Check the card every few days for any insects. If you have some on the card, you probably have many more on the plant itself.

What if You Detect an Infestation?

The most common pests are aphids, fungus gnats, mealybugs, scale, spider mites and white flies. See this resource for bug-specific instructions.

For all infestations, the first thing to do is to move the affected plant away from all other plants. Quarantine!

Then, take the plant to the bathtub/shower and spray it with water. Many bugs are tiny and are easily washed off the plant. Be sure to rinse both upper and lower leaf surfaces. After the plant has fully dried, use a light-weight horticultural oil or insecticidal soap to smother the pests. Reapply the oil/soap every 10-14 days for two more applications for the best control.

If you detect small bumps, wipe the plants with a cotton ball soaked in rubbing alcohol and remove the bumps if possible.

If you detect pests in the soil, it’s often caused by overwatering. Reducing the amount of water, or watering your plants from the bottom instead of the top should take care of the problem. Spraying the soil lightly with insecticidal soap occasionally often helps as well.

Resources

How to Get Rid of Bugs on Houseplants
Common Houseplant Insects & Related Pests
How to Get Rid of Common Houseplant Pests

Spider mites


Advice, Houseplants, Insects

Bringing in Your Tropicals for Their Annual Winter Spa Treatment

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By Mary-Jane Pilgrim, Master Gardener

Note: The article was also published recently in the Peterborough Horticultural Society September 2021 newsletter. Apologies to PHS members who have already enjoyed it!
—

If your houseplants are on “vacation” on the back deck this summer, then at around this time you should think about getting them ready to move back inside for the winter.

Bring your houseplants indoors before night time temperatures dip below 7 or 8 degrees (C).  Most tropicals will suffer damage at temperatures below 5 degrees, a few even below 10 degrees.

Sudden changes in temperature, light, and humidity can be traumatic to plants, resulting in yellowed leaves, dieback, wilting, and even death. To prevent shock when you bring houseplants back indoors, expose plants gradually to reduced lighting.

Before moving day, inspect plants for insects and diseases, and treat as appropriate before bringing plants back inside.  Spray them a couple of times over a 2 week period with a mild soap and water mix so that you don’t bring bugs from outdoors in with your plants.  Alternatively, soaking the pot in a tub of lukewarm soapy water for about 15 minutes will force insects out of the soil. Allow the plant and pot to dry completely afterwards.  If snails, earthworms, or other insects burrowed in the soil, you might want to repot the plants, placing a piece of wire screening over the drainage hole to keep them out next year.

Personal anecdote:  A couple of years ago, I brought a large cactus planter inside without inspections or the soaking method. The next day, we found a curious “deposit” left behind by some unknown critter on our kitchen floor and we kinda freaked out.  We set live traps in the house and were on high alert for a chipmunk or squirrel or even something huge with big teeth that could drag us out of bed by the big toe.  It was a little bit traumatic.  A day or so later, my son found a large toad in the living room and we connected the dots.  Turns out that toads leave very large deposits for their body size (Google it!) and closer inspection of the cactus planter showed an open hibernation hole. Whew!

Moral of the story? Check your plant pots for toads too!

Toad ‘deposit’

Toad — they’re looking for prime hibernation locations at this time of year.
Advice, Bees & Pollinators, Insects, Websites

Stripey Things in the Garden

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By Mary-Jane Pilgrim, Master Gardener

A couple of weeks ago, Laura Gardner posted an article in this blog about insects in our gardens in general. I’d like to follow up on that post with one specifically addressing the variety of stripey flying insects in our gardens.

Bees, wasps and hornets are often lumped into one stinging group but is important to understand the difference between bees, wasps and hornets in order to appreciate their significance in the garden.

Bees are mostly hairy, have fat legs and short fat bodies. They eat pollen and nectar, and in the process of gathering these, they pollinate flowers. Bees die after they sting. There are over 400 discovered varieties of bees in Ontario.

Honey bees at work, Pixabay.

Wasps and hornets have hairless bodies and tend to be long and sleek with a narrow between the abdomen and thorax. They are predators and for the most part they eat other insects. A hornet is a larger type of wasp with black and white rings instead of black and yellow. The most common type of wasp in Ontario is the yellow jacket, but there are three others in this region: Bald faced hornets, paper wasps and mud dauber wasps. Wasps and hornets do not die after they sting, and can sting multiple times.

Wasp, Pixabay.

For the most part, wasps are not important pollinators but they are hunters and their prey is other insects. They play an important role in protecting your plants. Wasps spend their summers seeking out aphids, flies, caterpillars and other bugs – many of them pests – to feed to their larvae. Hundreds or even thousands of larvae can be produced each year in a paper wasp hive, so they look after a lot of bugs!

How can we coexist with these scary, menacing fliers? Wasps sting when you threaten them. If you get stung it is probably your fault – it may not be intentional – but you are still to blame. If you swing at them or make sudden movements, they will feel threatened and there is a good chance you will be stung. The best way to avoid the pain is to treat bees and wasps with respect. Move calmly and deliberately, give them space to go about their business, and they will ignore you. If you do get stung, wash the area with soap and water and apply an ice-pack. You might want to take an anti-histamine tablet or use an anti-histamine lotion. If you have an extreme reaction, get to the ER fast. Otherwise, try a fresh-cut raw onion (it has enzymes that counteract the venom), anti-perspirants that contain aluminum zirconium, After-Bite, or a simple paste made from baking soda and water to ease your suffering.

Most people don’t want to have wasps living alongside them, but if you can possibly leave the nest alone, it is advisable to do so. After all, wasps are so common that even if you can’t see a nest, it’s probable there’s one nearby. The wasp colony will die when the cold weather hits. If the nest is left in place it is unlikely that wasps will build there again the following year, so you can dispose of any visible wasp nests in winter or early spring. The only wasps to over-winter are the fertilized queens which start new colonies in the spring.

Wasp nest, Pixabay.

The best way to deal with wasps is to minimize their numbers by deterring them from the area. Do not keep any food (including your pet’s) lying around. Keep drinks covered when outdoors and always ensure that garbage cans are tightly sealed. Also, keep any fallen fruits from nearby trees, shrubs and gardens picked up as their sweet juices attract the wasps.

Fake wasp nests are available to the homeowner to hang in trees near the house. Since the wasps are territorial, they will probably set up housekeeping somewhere else.

Last year, we had wasps nesting in two places under our vinyl siding. Since they were near our back door, we tried some of the sprays available but found that they weren’t effective. One day, I bravely (and quickly) put duct-tape over the nest entrances, and the problem was solved instantly. If only I’d tried that before heading to the hardware store!

If you can find a way to coexist with the majority of these insects, your gardens will thank you.

Resources:

Why Wasps are Good for Gardeners
Understanding Wasps–They are not Evil!
Bees, Wasps and Hornets: What You Need to Know
Bee Species in Canada

Books, Butterflies and Moths, Garden Cleanup, Insects, Planting, Websites

Lending Insects a Helping Hand in our Gardens

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By Laura Gardner, Master Gardener in Training

When some of us think of insects, it is common for them to be thought of in a negative light. Some of our earliest childhood memories include being stung, bitten, or just plain scared by the sight of them. I can remember running screaming from an outhouse at a provincial park when I was about five years old. What was so scary? It was the sight of a Yellow Garden Spider (Argiope aurantia) hanging in its web in the stall. Fortunately, the experience didn’t make me fear or dislike spiders and as a gardener I know how beneficial they are to have around. While some insects certainly do deserve our scorn— invasive species such as the LDD moth (Lymantria dispar dispar); Emerald Ash Borer (Agrilus planipennis); Japanese Beetle (Popillia japonica), etc.—by and large, the majority of insects are harmless and beneficial. Not long ago, I saw a couple—perhaps grandparents, out for a walk with their grandson. One of them was urging the young boy to stomp on an ant on the pavement, calling out “Get it! Get it!” It was disheartening to see. It is experiences like this that call for a shift in our thinking about insects.

Bumblebee (Bombus sp.) on False Sunflower (Heliopsis helianthoides)

I recently got a sneak preview of a book by British entomologist Dave Goulson called Silent Earth: Averting the Insect Apocalypse (Harper Collins). It is to be published this Fall (September 2021). The copy I reviewed was an e-book proof and so page numbers referred to here may change in the final published copy. Goulson’s work is primarily focused on bumblebees and as the founder of the Bumblebee Conservation Trust in the UK, he is dedicated to reversing the decline of them. He is also known for his work that was instrumental in influencing the European Union’s decision to ban neonicotinoids in 2013. Goulson wrote this book in an effort to bring more public attention to the recent and rapid decline of global insect populations—which are critical for our planet’s survival. He also explores the chief causes of insect declines such as habitat fragmentation, industrial farming practices, pesticides, climate change, and non-native insect diseases (p. 71) and provides suggestions for readers that can help support insects—especially gardeners.

Bumblebee (Bombus sp.) on Sweet Joe Pye Weed (Eutrochium purpureum)

Here are a few highlights from the book:

Goulson refers to a phenomenon called “Shifting Baseline Syndrome” where humans tend to only see their current world as “normal” and are unable to detect changes over time. Humans also tend to have something called “personal amnesia” in which they downplay the extent of change (p. 64-65). With these points in mind, it is no wonder that most people would not know that insect populations have recently declined by as much as 75% (p. 50) and that there have been parallel declines in populations of insectivorous birds (p. 58). One bird that I remember as a child that I haven’t seen since is the Eastern Meadowlark (Sturnella magna). This species is one of those that depends on insects in its diet.

One concern that the author has is the level of human awareness of the existence of the natural world. It is important to learn the names of plants and animals—otherwise they cease to exist. If they don’t exist, their importance can’t be recognized. Astonishingly, in 2007, some of the words eliminated from the Oxford Junior Dictionary included words such as acorn, fern, moss, clover, kingfisher, otter, among others (p. 225).

87% of all plant species require pollination in order to flower, produce fruit/seeds, and ensure perpetuation of the species. This includes 75% of all agricultural crops (p. 26). Most of this is performed by insects and a large part is performed by those other than bees—flies, ants, beetles, wasps, moths and butterflies. A world without insects means that we would need to subsist mainly on cereal crops as these can be wind-pollinated. I can’t imagine going without fruits such as strawberries, apples, cherries, raspberries, and even my morning coffee (p. 26).

Insects are not only important pollinators, but they assist in the development of healthy soils. Not only do they help to aerate soil, they are valuable decomposers of organic matter—participating in a process along with bacteria that help make nutrients more available to plants (p. 29, 31).  As biological control agents, predatory insects such as Lady Bugs (Coccinellidae spp.), Lacewings (Chrysopidae spp.), Ground Beetles (Carabidae spp.), Wasps (Vespidae spp.), etc., can help us reduce the need for pesticides.

Blue Mud Dauber (Chalybion californicum) on Swamp Milkweed (Syriaca incarnata)

What can we do to help?

Despite the current state, Goulson is optimistic that insect declines can be stabilized or reversed because they are generally good at reproducing—we just need to support them better (p. 216). Here are some ideas:

  1. Learn how to identify the difference between harmful and beneficial insects. The majority (95%) are the latter.
  2. Reduce or avoid the use of pesticides and give beneficial predatory insects a chance to take care of the problem first (p. 277). Even so-called organic treatments such as diatomaceous earth, BTK, horticultural oils, etc. need thoughtful consideration before use as they can harm harmful as well as beneficial insects.
  3. Learn how to differentiate between irreversible and cosmetic damage in your plants. Accept that plants are meant to be food sources for insects and some imperfections and damage is ok. Give up growing ornamental plants that are persistently defoliated by certain insects (e.g. Asiatic Lilies).
  4. Incorporate a wide range of native plants that flower throughout the season in your garden to attract beneficial insects. One of the best late flowering perennials is New England Aster (Symphyotrychum novae-angliae). It provides a valued food source for migrating Monarch butterflies. Some of the best food sources for insects are early flowering trees such as Serviceberry (Amelanchier spp.), Maple (Acer spp.), and Crabapple (Malus spp.).
  5. When using mulch in flower beds, leave some soil exposed so that ground nesting bees can have easy access. Some solitary wasps such as Mud Daubers (Sphecidae spp.) also need easy access to bare soil in order to glean material to build their nests.
  6. Reduce lawn and use the space for more plants. Reduce mowing of the lawn that exists. Allow a corner of your garden to “grow wild” and “get messy.”  (p. 277).
  7. Choose native plants over “nativars.” A nativar is a cultivated variation of a native plant. Some are supportive of pollinators but many are sterile or lack pollen and therefore are unable to provide food. The ones that are most likely to be the least supportive will have features such as double blooms, different leaf colours, etc. Reduce planting of ornamental annuals like Petunias, Begonias, Pansies, etc. because of their tendency to have no pollen or nectar (p. 233). That being said, some of these plants can still be enjoyed.
  8. Choose a range of plants that support the broadest number of insect species. While Milkweeds (Asclepias spp.) are in the limelight as being supportive of Monarch Butterflies (Danaus plexippus), compared to some other plants, they only support 12 Butterfly and Moth species (Tallamy, Bringing Nature Home). Goldenrods (Solidago spp) support 115 different species. Some, like Canada Goldenrod (Solidago canadensis) can be aggressive in small gardens but there are more restrained types such as Blue-Stemmed Goldenrod (Solidago caesia), and Zigzag Goldenrod (Solidago flexicaulis).
  9. Avoid aggressive fall and spring clean-up of leaves and hollow, dead stems. Doug Tallamy describes the practice of waiting 7-10 consecutive days of 10 degree C. temperatures for insects to emerge as myth as many insects emerge at different periods throughout the season. For example, Io (Automeris io) and Luna Moth (Actius luna) emerge around mid May (Tallamy, Leaf Litter: Love it and Leave it).
  10. Recognize that commercially produced “Bee Hotels” can become populated by non-native bees such as European Orchard Bee (Osmia cornuta), Horned-Face Bee (Osmia cornifrons), and Blue Mason Bee (Osmia coerulescens) as well as native bees (p. 135). If used, periodically clean them so as to reduce mites and fungi that can be harmful to the bees.
  11. Reconsider taking up beekeeping as a hobby. The European Honey Bee (Apis mellifera) threatens native bees because they take the lion’s share of available plant pollen (p. 139). It is also not a good strategy to rely on one species for pollination in case something happens to that species (p. 33).
  12. Raise awareness and share your knowledge with family and friends. You can convince others that insects need our help if they realize they themselves will be personally impacted by their decline (p. 216).

Selected Resources

Holm, Heather. Pollinators of Native Plants: Attract, Observe and Identify Pollinators and Beneficial Insects with Native Plants (Pollination Press, 2014).

Tallamy, Doug. Bringing Nature Home: How you can Sustain Wildlife with Native Plants (Timber Press, 2009).

Tallamy, Doug. Leaf Litter: Love it and Leave it. April 2021. Online: https://tinyurl.com/4jphhnbc

Walliser, Jessica. Attracting Beneficial Bugs to your Garden: a Natural Approach to Pest Control (Timber Press, 2013).

Xerces Society for Invertebrate Conservation. Visit https://xerces.org/publications to view and download a wide range of factsheets and other guidance documents concerning beneficial insects, native plant lists, pesticides, habitat construction, and more.

Monarch Butterfly Caterpillar (Danaus plexippus) on Swamp Milkweed (Syriaca incarnata)
Bees & Pollinators, Butterflies and Moths, Insects

Hosting butterflies

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By Lois Scott, Master Gardener

Life has been busy in my garden lately, and I don’t necessarily mean me! My husband Ray and I have been enjoying the array of pollinators that are busy in the garden. What has us particularly excited is seeing species of butterflies that we have not noticed in the garden before. For example, Ray identified a Large Wood Nymph butterfly (Cercyonis pegala) that I noticed feeding on heliotrope. Although it spent a lot of time feeding on the heliotrope this is not a host plant for this particular butterfly. According to The Audubon Society Field Guide to North American Butterflies host plants for the Large Wood Nymph are native grasses such as Little Bluestem (Schizachyrium scoparium).

Large Wood Nymph butterfly

So, what exactly is a host plant and why is it important? Host plants are plants that an organism, (larva) lives on and lives off of. A well-known example is the Monarch butterfly. It will feed on a number of nectar plants including milkweed but Monarch larvae only feed on milkweed (Asclepias) species. Milkweeds are the Monarch’s only host plant. Important pollinators like butterflies and moths need host plants on which to lay their eggs and enable the subsequent larvae to have a food source. The photo below shows Little Bluestem (Schizachyrium scoparium) in the foreground is a host plant while the Mexican Sunflower (Tithonia rotundifolia) behind it is a nectar plant.

Little Bluestem grass and Mexican Sunflower provide host and nectar sources (respectively).

According to the Ottawa Field-Naturalists’ Club (OFNC) butterflies need plants that are good sources of nectar, sun, shelter from the wind, and host plants on which to lay their eggs.  Yes, larvae eat the leaves on the host plant but typically do not cause serious damage.  Along with providing a list of plants for nectar sources this site gives a list of host plants for larvae for specific butterflies.  Many of the host plants are trees including birches, willows, dogwoods, oaks, hops, cherries and hackberries to name just a few.  Other host plants include native wildflowers and grasses.

The OFNC site provides more details on providing the most desirable conditions for butterflies and makes the point that to restore butterfly populations we need to recreate suitable habitats for them. This is another list of valuable host plants.

If you are interested in attracting more butterflies consider adding some of these valuable host plants to your garden. Many of these plants can be sourced at Peterborough’s Ecology Park where you can also get expert advice on suitable plants for your garden conditions.

Advice, Bees & Pollinators, Garden Cleanup, Information, Insects, Websites

Don’t Spring into Spring Clean-Up just Yet

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By Anica James, Master Gardener in Training

Spring is finally here, a time for new beginnings. The days are getting longer, birds are singing their hearts out and the snow has melted for the most part, but it’s still too soon to do any kind of clean up in your yard. It may be tempting to get out the rake or leaf blower just because it’s sunny and leaf bags are on sale at your local box store, but we need to hold off just yet for the sake of helping other creatures and pollinator species who are still asleep.

Although we are all anxiously waking up from our own personal winter hibernation–whether it be mental or physical–many creatures around us are still sound asleep in the leaf litter or below the mulch and we should not disturb them just yet. When you clean up your yard too soon, all for the sake of aesthetics or curb appeal, you are essentially removing all of the beneficial insects in your vicinity, like those responsible for making your flowers bloom or for your fruit and vegetable plants to produce food.

Some beneficial pollinators overwinter in the hollow stalks of perennials and under rocks. Examples of insects local to us that are still in diapause state are butterflies (like Mourning Cloaks or Question Marks), lacewings, ladybugs, mason bees and parasitic wasps, which all spend the winter either as pupae or adults hidden away in your yard. Even Luna moths and black swallowtails spend the winter months in cocoons or pupa that look just like a crumpled brown leaf, so be on the lookout for those.

It is best to wait until the temperature is consistently 10 degrees Celsius before you start raking leaves, turning soil, or using a leaf blower. Personally, I like to play it safe with the 10 For 10 rule: 10 degrees for 10 days. This allows nature to take its course and it allows me to have enough time to observe my property and familiarize myself with the various kinds of flora and fauna that emerge post-winter.

If you do decide you feel so inclined to “tidy up” this early, do it with purpose and be mindful of the sleeping and living creatures that are still hidden away. Take your time, look for any signs of beneficial insect stages and either take note and leave it for a later date, or carefully cut and set it aside in a natural area so solitary bees and others insects can still use the refuse for food or shelter. Refrain from adding more mulch because it can trap certain kinds of beneficial bees, beetles and flies that burrow in the ground (almost 70% of Canada’s bee species nest underground). For more information on how to properly “clean up” your yard read Nesting and Overwintering Habitat for Pollinators and Other Beneficial Insects PDF by the Xerces Society.

But again, the best thing to do is wait and to try to remove as little from your property as possible.

So in the meantime, what can you be doing instead of gardening?

  • Get outside, go for walks, enjoy the little things; notice the bulbs emerging naturally and gracefully from the cool earth, poking their way through the leaf litter- now is the time to enjoy the scilla, crocus, pushkinia, galanthus and helleborus
  • Continue to sow vegetable and annual seeds indoors and plan your garden; what are your goals for this year, however big or small?
  • Early spring is the best time of year to be on the lookout for invasive pests and plant species and begin to develop an Integrated Pest Management plan; gypsy moths, garlic mustard, european buckthorn, and goutweed are commonly found throughout the Peterborough area
  • Focus on spring cleaning your tools, your patio furniture, tidying your deck, potting bench or shed; put more focus into the inanimate things
  • Celebrate the beginning of spring by honouring the maple tree, it’s delicious sap and syrup, and the work that goes into providing us all with natural liquid sugar; maybe consider ordering a maple for your own yard
  • Repot indoor plants if needed
  • Read up on and think about ways you can increase pollinator habitat on your property or within your community, no matter the scale

There is so much that you can do while resisting the urge to rake or blow. Relax, enjoy the much needed sunshine that the vernal equinox has brought us after the long winter and try to go at the same pace nature is. Patience will pay off in the long run once you remember that gardening isn’t just about plants.

Great resources for more information about pollinators that spend the winters in our gardens and why we should hold off until mid-April to start yard work: