I have to give the folks at The Xerces Society a lot of credit. They took the rare step of publishing a book on native pollinators (Attracting Native Pollinators), before coming out with their new book, Gardening for Butterflies. Both are excellent resources and well worth purchasing.
Gardening for Butterflies
Butterflies are far easier to “sell” in our bee-phobic, wasp-phobic, beetle-phobic society. Butterflies are charismatic insects, but often rather inefficient pollinators as they typically have limited contact with pollen. The authors of Gardening for Butterflies point out that, even so, butterflies do provide valuable pollination services, and some plants even rely upon them.
Nature is full of surprises, and new research from Mary Jane Epps at NC State and two other colleagues, has shown that butterflies are the best pollinators of Rhododendron calendulaceum (Flame Azalea). Finding a rare example of wing pollination, they discovered that the Eastern Swallowtail Butterfly is the most efficient pollinator of native Flame Azalea – the Swallowtail transfers pollen from the plant’s anther to the stigma, on its wings! It makes you wonder how many other examples of flora-fauna mutualism we don’t yet understand!
Gardening for Butterflies has five contributing authors whose collective expertise makes for a book filled with useful facts and practical information. They give the reader the happy news that, “a small yard with just a few native plants can attract and sustain dozens of butterfly species” and “your efforts will support countless other creatures as well…”
Butterflies in Trouble
The authors explain that many butterfly species are in trouble, with five species becoming extinct since 1950, twenty-five species listed as endangered nationwide, and four species listed as threatened. They cite the NaturServe study that determined 17% of the 800 butterfly species in the U.S. are now at the risk of extinction. Many of these “at risk” species are what the authors call “rare endemics” – species that have a narrow geographic range or very specific habitat requirements.
How We Can Help Butterflies
The authors also note what any gardener or nature-lover can deduce through their own observation – many common butterfly species are also in decline. Why? The authors explain that butterflies face a number of threats including loss of habitat, fragmentation of habitat, climate change, disease, pesticide use and a proliferation of invasive plants. Gardening for Butterflies offers the information we can use to improve the plight of challenged butterflies. “A well-designed garden can offer all a butterfly or moth needs to complete its life cycle,” according to the authors. Note that supporting non-profit conservation and environmental organizations, like the Xerces Society, will help accomplish what you cannot do personally.
Identifying Butterflies and the Plants They Use
The first order of business is to be able to identify butterflies and what they need. A description of butterfly families and their life cycle is covered, as are the basics of nectar plants and host plants for butterflies. I was pleased to see the explanation on native thistles (the genus Cirsium) and their importance to butterflies and moths. Not just compelling nectar plants, some native thistles are host plants for butterfly caterpillars. The authors explain that thistles have gotten a bad name due to the introduced, thuggish thistles such as Canada Thistle (Cirsium arvense) – actually native to Eurasia – and Bull Thistle (Cirsium vulgare) – native to Eurasia and northwestern Africa. Examples of native thistles are mentioned, including Cirsium discolor (Pasture Thistle) for the Northeastern U.S. and Cirsium occidantale (Western Thistle) for Western states.
Following in the footsteps of noted lepidopterist and author, Dr. Doug Tallamy, the authors discuss the top three trees for butterflies – Quercus species (oaks), Salix species (willows) and Prunus species (Chokecherry, Black Cherry, et. al). Oaks are host plants for an incredible array of butterflies and moths, while willows and cherries are both larval hosts and nectar plants. The authors also mention native grasses and sedges as host plants, as well as some native vines including Aristolochia species (pipevines), Passiflora species (passionflowers), and Lonicera sempervirens (Coral Honeysuckle) – these last two are also nectar sources.
The Mixed Message of Butterfly Bush
Warming the cockles of my heart, Gardening for Butterflies takes a shot at Butterfly Bush (Buddleia davidii) an introduced species from Asia, listed as a noxious weed in Oregon and Washington states (and a species of concern in a number of other states). Although its nectar is very attractive to butterflies, I think the plant is better named “Nectar Bush” as it is not a host plant for any of our butterfly species. The authors recommend that you cut the spent blooms on Butterfly Bush to prevent seed dispersal or (better yet), substitute with native plants.
Regional Plants for Butterflies
Gardening for Butterflies includes a list of top butterfly plants by region, followed by a description of individual plants. Principles of butterfly garden design are discussed with some of the key points being – create large blocks of color, aim for continuous bloom, make the most of sunny spots, and provide brush piles and unkempt areas for shelter. A chapter on plant selection, installation and maintenance follows, with the important suggestion to favor natural pest control (beneficial insects) in lieu of pesticides, which can be lethal to the very insects you are trying to support.
Gardening for Moths
A chapter on gardening for moths is a welcome addition – something that most people never even consider – until they see a spectacular creature like a Luna Moth. Moths that are active during the day may feed on the same plants that attract butterflies or bees, but also add some night-blooming plants in your garden for nocturnal moths. A list of best moth garden plants by region is included in the book.
Beyond the Garden
The chapter “Helping butterflies beyond the garden fence” – offers some additional measures we can take to support these beautiful creatures – from eco-roofs for butterflies to planting corporate campuses, parks and greenspaces. Whether you have a garden or just a love of butterflies, Gardening for Butterflies will give you the tools you need to become a butterfly steward. Pick up a copy and buy one for a friend, too.
Kudos to the authors for a job well done: Scott Hoffman Black, Brianna Border, Candace Fallon, Eric Lee-Mader, and Matthew Shepherd.
Enter the EcoBeneficial Book Giveaway by May 15, 2016 to win a copy of Gardening for Butterflies, generously sponsored by Timber Press.
From Kim Eierman at EcoBeneficial!