As the number of monarch butterflies continues to decline, scientists have calculated that more than 1.8 billion new milkweed plants need to be planted in order to provide monarchs with enough places to lay their eggs and recover from the brink of extinction.
“‘To put that in context, that’s more than three milkweed plants for every man, woman and child in the United States,’ said Karen Oberhauser, professor and conservation biologist in the University of Minnesota Department of Fisheries, Wildlife and Conservation Biology.”
The good news is that milkweed – the only plant monarch butterflies will lay their eggs on – is easy to grow. The milkweed family contains over 100 species. Wisconsin alone has native milkweed species that will grow in wet spots, dry spots, sunny spots, and shady spots. Milkweed is able to thrive in roadside ditches and along the edges of farm fields, and was once so abundant across America that many cities labeled it a noxious weed and forbade property owners to plant it.
Now, attitudes towards milkweed are changing. But attitudes are not enough. If we want to protect monarchs before it’s too late, we need to actually plant milkweed in our yards – and lots of it.
Any native plant nursery should have local milkweed species available as plants and seeds. Right now is the perfect time of year to add some to your garden.
An important distinction in natural gardening is between native plants and non-native plants. A native plant is one that has evolved in the region where it is planted, and which typically has developed important relationships with other plants and animals in that region. A non-native plant is one that is planted far from where it evolved. It often contributes little or nothing to the local community, because the animals in its new home cannot eat it, or may not recognize it as a potential food source.
A cultivar is a type of plant that didn’t evolve anywhere. Rather, a cultivar is the plant equivalent of a domestic animal. The same way that modern cows never existed in the wild and are the result of careful breeding, cultivars have been bred from wild plants to bring out desirable characteristics.
The characteristics that are desirable to people, however, are often of no value to wildlife. Double-flowered cultivars, for example, are considered especially attractive in a garden. These flowers are worthless to pollinators, though, because they are mutant plants that have a second row of petals instead of having the structures that produce pollen and nectar.
Nativars are cultivars of native plants. Well-meaning gardeners seeking to support wildlife are often tripped up by nativars, which are advertised as native plants, but which can be as useless to pollinators and other animals as cultivars of non-native species.
Cultivars and nativars can be recognized by the names on their tags. Plants should always be labeled by their scientific names, which help gardeners ensure they’re getting the right species. A plant that has a second, English name in quotes after its Latin name is a cultivar or nativar, not a true species.
The rusty-patched bumble bee recently became the first kind of bee to be added to the endangered species list.
This bee used to range widely, from Minnesota to Maine, and as far south as Georgia. Now, it’s only found in isolated pockets.
One of those pockets is in Madison, Wisconsin. The Arboretum reports that they still have rusty-patched bumble bees, though many fewer than in the past.
The fact that there are still some left, though, means that residents of Madison can help the bees, allowing them to increase their numbers and begin to spread back into areas where they used to be found.
Unlike some bees, which rely on specific kinds of flowers, bumble bees can gather food from many different plants. Adding plants to your yard that flower throughout the season, and avoiding the use of pesticides, can help bumble bees. Rusty-patched bumble bees also need a little bit of bare soil in which to build their underground nests and lay their eggs.
Bumble bees are different from honey bees, which are a non-native, domestic species. Many well-intentioned people who are worried about pollinators try to help by taking up beekeeping. As some have put it, being concerned about pollinator decline and putting a beehive in your yard is like trying to address declining bird populations by getting some chickens. Adding more hives of honey bees to an area can actually decrease the quality of the local habitat for native bumble bees, because it increases competition for the resources that bees need.
“A Ghost in the Making” is a short documentary about the rusty-patched bumble bee. A segment in the middle of the film focuses on Madison’s Arboretum.
Fall has arrived in the northern hemisphere, and leaves will soon be changing colors. We’ve all heard why they do this: the green color is created by chlorophyll, a substance key to photosynthesis, and when the chlorophyll is lost at the end of the summer, leaves reveal their true colors.
Now, some scientists think this story is wrong. They believe that, instead, trees actively work to create their brilliant fall colors.
Why would trees do this? One challenge plants face in life is being attacked by insects. To combat this, plants produce a variety of chemicals that deter insects from eating their leaves or burrowing in their bark.
Just as chlorophyll creates a green color in leaves, some of these insect-deterring chemicals create bright yellows, oranges, and reds. The more chemical a tree stores up, the more vibrant the colors.
In the same way that a male bird puts on showy colors in spring to prove that he is a healthy mate, trees display dramatic autumn hues to tell insects, “I’ve invested in defenses against you; don’t bother trying to attack me.”
Colorful fall leaves may therefore be not only a defensive strategy, but a method of communication – providing further evidence that plants are intelligent.
Habitat is an area where a plant or animal can live.
Whether or not a particular area is habitat depends on which species’ perspective you’re looking at it from. For example, the ocean is habitat for a whale, but is not habitat for a squirrel.
To count as habitat, an area must provide for a plant or animal’s needs. For example, habitat for a bird must include water sources, appropriate food, safe shelter, and a place to nest. Habitat for dandelions must include plenty of sun.
Lawns count as habitat, since by definition grass lives in them. However, few other species can meet their needs in or around a lawn. Overall, lawns are not very good habitat.
Natural yards provide better habitat by inviting in many plant species. These plants, in turn, provide much of what an insect or bird needs to call a place habitat.
Habitat loss is a major factor in species extinctions. Hundreds of North American bird species, as well as popular insects like bumblebees and monarch butterflies, are in decline. If we exchange poor habitat in our yards for better habitat, we can increase these species’ chances of survival.
Wisconsin has just released a State Pollinator Protection Plan. The full document can be found here.
The goals of the plan are to increase public understanding of issues facing pollinators, and encourage voluntary actions to help pollinators. The plan will not create any new regulations.
“Urban flower gardens often harbor diverse pollinator communities, but in areas dominated by skyscrapers or grass lawns pollinator diversity tends to be low,” the plan explains, in its opening section. The second section of the plan is divided into four parts, each describing what a specific group of people can do to help pollinators.
One of these sections, “Best Management Practices For Improving Pollinator Habitat in Gardens & Lawns” is directed towards homeowners. It is just a few pages long and can be read on its own. It begins on page 14 of the PDF linked above. The section suggests landscaping with a diversity of native plants that are suited to the site conditions. It also encourages homeowners to “leave things a little messy” – bare soil, leaf litter, and brush piles are all important habitat elements for pollinators.
The plan is currently in a public comment period. Its official website lists the following instructions for submitting comments:
Email comments by Friday, Feb. 19, to DATCPAgriculture@wisconsin.gov. Written comments may be mailed to: DATCP, ATTN Pollinator Protection Plan, PO Box 8911, Madison, WI 53708-8911. They must be received by Feb. 19.
A guild is a group of plants that work well together. In other words, they have complementary functions.
(When such a grouping of plants assembles itself naturally, it is called a community. A guild is a group of plants brought together by a gardener.)
To explore this concept, let’s look at an example of a guild. This guild centers around a linden tree, a common species in Madison, and its primary purpose is to provide habitat for pollinators – a recently-adopted goal of the city.
Plants in a guild work together in multiple ways. To start, they generally differ in size and requirements. For example, a linden tree is large and needs sun, while the other plants in this guild are small and tolerate shade. Thus, the other plants can be placed under the tree, conserving space while giving every member of the guild what it needs.
Plants in a guild normally also differ in their functions. In this guild, all the plants perform the function of providing habitat to pollinators. But, each plant also provides other functions. In this way, the guild collectively fulfills many purposes. Let’s look at the additional functions performed by this guild.
- The leaves of linden trees can be eaten by people.
- Early-blooming flowers – like crocus, hyacinth, and daffodil – and late-blooming plants, such as sage and 4 o’clock, provide cheerful color in spring and fall.
- Rose apple (or the smaller rugosa rose) and turtlehead are medicinal.
- Cup plant and compass plant form a screening hedge and attract birds.
- Lovage and coneflower draw up nutrients from deep in the soil, making those nutrients available to plants with shallower roots.
- Comfrey can be cut back and turned into compost almost endlessly.
- Mint, dill, caraway, parsley, and fennel serve as groundcovers and are, of course, very tasty!
Advanced permaculture practitioners, who are familiar with the properties of many plants, can create their own guilds. For new practitioners, examples to borrow can be found by googling “permaculture guilds”.
Thanks to Bryce Ruddock of Midwest Permaculture for this guild example.