Archives For Kay Havens

Did you know that one in every three bites of food you take required a pollinator visit? Pollination is essential for many of our favorite foods—from almonds to vanilla, and so many fruits and vegetables in between.

The decline of pollinators around the world is threatening not only our food supply but also the function of plant communities and ecosystems. Multiple factors play a role in pollinator decline, including land-use changes, pesticide use, climate change, and the spread of invasive species and diseases.

The well-documented plight of the iconic monarch butterfly has become emblematic of widespread pollinator decline. Perhaps many of you, like me, have childhood memories of setting out with a butterfly net and a jar with nail holes in the lid. I recall with pleasure catching and admiring monarchs up close until it was time to set them free. I worry that children may not have that simple pleasure much longer. After their previous all-time low population count in 2012–13, monarch numbers dwindled even lower this past winter (2013–14), when monitored in their overwintering location in Mexico.

PHOTO: A cluster of monarch butterflies rests on a plant, entirely covering it.

Now a much less common sight: a monarch butterfly cluster. Image by Christian Mehlführer (Own work) [CC-BY-3.0], via Wikimedia Commons

PHOTO: A monarch sips nectar from common milkweed on the Dixon Prairie.

A monarch sips nectar from common milkweed (Asclepias syriaca) on the Dixon Prairie.

In the case of the monarch, several factors are likely contributing to its rapid decline. Loss of forested wintering grounds; loss of the milkweeds, which are their larval host plants; severe weather events; and a reduction of nectar plants along their migration routes due to drought have probably all contributed. Three leading monarch experts, Dr. Lincoln Brower, Dr. Chip Taylor, and Dr. Karen Oberhauser, have all cited GMO (genetically modified) crops as a leading factor in the decline. Milkweed (Asclepias sp.) once thrived on the edges of farm fields throughout the Midwest. Modern farming techniques use herbicide-resistant crops coupled with an increased use of herbicides; the native milkweeds are disappearing, and as they go, so do the monarchs.

Make Way for Monarchs

Click here for registration and schedule information.

On Friday, June 6, the Chicago Botanic Garden will host a symposium by Make Way for Monarchs: Alliance for Milkweed and Butterfly Recovery (makewayformonarchs.org). Members of this group conduct research on monarch butterfly recovery and promote positive, science-based actions to avert collapse of the milkweed community and the further demise of the monarch migration to Mexico. They aim to promote social engagement in implementing solutions in midwestern landscapes through collaborative conservation. Speakers include Gary Nabhan, Lincoln Brower, Chip Taylor, Karen Oberhauser, Laura Jackson, Doug Taron, and Scott Hoffman Black. They will discuss monarch decline and tangible solutions we all can help implement. Mr. Black will also present a lecture on monarchs at World Environment Day, Saturday, June 7.

PHOTO: Closeup of a single, tiny butterfly egg on the underside of a leaf.

Monarch egg on a milkweed leaf by Forehand.jay (Own work) [CC-BY-SA-3.0 or GFDL], via Wikimedia Commons

There are things all of us can do: from planting milkweeds and other native plant species that provide nectar throughout the growing season, to minimizing pesticide use, and to supporting organic farmers. We can also become citizen scientists, reporting monarch observations to programs like Monarch Watch and Journey North, or working with the Monarch Joint Venture.

Perhaps, with our help, new generations of children will continue to know the joy of admiring the beautiful monarch butterfly, and then letting it go to continue its amazing migratory journey.

Learn more about pollinators at World Environment Day at the Garden on June 7, 2014.


©2014 Chicago Botanic Garden and my.chicagobotanic.org

This year, it sure felt like spring was a long time coming — especially compared to last year when it seemed that we went straight into summer! I wonder how the wildflower timing of spring compared to previous years in the Chicago area…

Mayapples, April 25, 2012

Mayapples, April 25, 2012

Mayapples, May 2, 2013

Mayapples, May 2, 2013

For several years now, I’ve been working on a web-based citizen scientist project, called Project BudBurst, with colleagues at the National Ecological Observatory Network (NEON). We study the phenology — the timing of natural events like blooming, fruiting, and leaf fall — of plants around the country. Our participants track when plants bloom in their area, and we compare the reports to records from other parts of the country.

You can help us collect data! Sign up to help at Project BudBurst.

For instance, I’ve been tracking when the first forsythia flower opens on the plants near the Garden’s front gate since 2007. The earliest bloom I have on record in that time was last year, on March 15, 2012. The latest first flower for this specimen was this year, on April 20, 2013. In 2007 and 2008, however, we also had first flowers in mid-April (April 16, 2007, and April 17, 2008, respectively). So, as we look back in time, this year’s bloom time doesn’t feel quite so late. In the graph below we show the variation in flowering dates (using Julian dates, which standardize for differences in dates between nonleap and leap years).

forsythia data

In the Chicago area, we have a wealth of phenology data collected by the authors of our local flora, Plants of the Chicago Region by Swink and Wilhelm (1994). While they were gathering data for their book, they recorded when they saw plants in bloom from the late 1950s to the early 1990s. They record the forsythia bloom period as April 25 to May 5. So, when we look still further back in time, our “late” spring is much earlier than it has been in the past.

I took a similar look at several other species, both native and nonnative, for which we have both Project BudBurst data and data from Swink and Wilhelm’s book. About 70 percent of the species have earlier flowering dates in the last six years compared to those recorded by Swink and Wilhelm. Some of the species that have advanced their flowering dates are in the table below.

Species Earliest First Flower Observations
Common name
Genus species
Swink & Wilhelm
1950s – 1990s
Project BudBurst
2007 – 2012
Days
Advanced
Forsythia
Forsythia x intermedia
April 25 March 15 -40
Spiderwort
Tradescantia ohiensis
May 14 April 12 -32
Dogtooth violet
Erythronium americanum
April 6 March 20 -17
Red Maple
Acer rubrum
March 20 March 6 -14
Mayapple
Podophyllum peltatum
May 1 April 17 -13
Lilac
Syringa vulgaris
May 3 March 20 -44
Black locust
Robinia pseudoacacia
May 9 April 20 -19
Bradford pear
Pyrus calleryana
April 15 April 13 -2

Plant phenology, particularly when plants leaf out and bloom in the spring, is remarkably sensitive to the annual weather. Looking at phenological records over much longer periods of time can tell us a lot about how the climate is changing. Many scientists are comparing contemporary bloom times with historic bloom times recorded by naturalists like Aldo Leopold in the early 1900s, and Henry David Thoreau in the mid 1800s, as well as records kept by farmers, gardeners, and others interested in the natural world. Two of the longest phenological data sets are those maintained for cherry blossoms in Japan (dating back to 900 AD) and for grape harvest dates by winemakers in Switzerland (dating back to 1480 AD).

Plants have so much to tell us, if we take the time to listen!


©2013 Chicago Botanic Garden and my.chicagobotanic.org

It’s not easy being green!

Kay Havens —  December 12, 2012 — 4 Comments
PHOTO: Prairie bush clover, a threatened species.

Prairie bush clover (Lespedeza leptostachya) in flower on the prairie in summer.

When I mention endangered species, what comes to most people’s minds are pandas, bald eagles, or maybe the gray wolf. It’s probably not Pitcher’s thistle (Cirsium pitcheri), prairie bush clover (Lespedeza leptostachya), or the host of other plants that are on the United States federal endangered and threatened species list. Plants make up nearly 60 percent of the species on the list, but the vast majority of the attention and the funding for species recovery goes to the “charismatic megafauna” — the mammals, birds, and fish.

Part of the reason for this discrepancy may be “plant blindness” — described by James Wandersee, co-author of Seeing Plants: A Theory of Plant Blindness, as “the inability to notice the plants in one’s own environment.” This inevitably leads to “the inability to recognize the importance of plants.” In other words, we tend to conserve what we notice and care about. I would argue that plants are even more worthy of our attention and concern! Not only do they beautify our landscapes and provide habitat for wildlife, they fundamentally support human life by giving us the air we breathe, the food we eat, and many of the medicines that cure our ills.  In fact, virtually all life on earth depends directly or indirectly on plants.

The chart below compares total endangered species spending by the federal and state governments for plants and animals over the last decade. As you can see, spending for plants has consistently remained at less than 5 percent of the total, and in 2011 was just 3.8 percent.

GRAPH

Scientists at the Chicago Botanic Garden are actively conducting research, managing lands and banking seeds to conserve our priceless plant diversity. Next time you visit, stop by the Daniel F. and Ada L. Rice Plant Conservation Science Center to view us in action and learn more about our plant conservation activities.


©2012 Chicago Botanic Garden and my.chicagobotanic.org