Ah March! How eagerly we await it as we look for signs of spring between blasts of freezing winds and occasional warm days. On one windy day in mid-March, the first returning turkey vulture flies along Sapsucker Ridge. A calm, warm day brings back a singing field sparrow or eastern phoebe. As the earth thaws, American woodcocks perform their sky dance over First Field. By the end of the month, the first wildflower, a coltsfoot, lifts its golden disk sunward.
But last March wasn’t March as I have known it for the 40 years we have lived here on our west central Pennsylvania mountaintop. While the songbirds returned on schedule, the plants responded to the early, almost continual, May-like temperatures, by breaking all our previous blooming records. Instead of the steady spring progression of wildflowers, from late March to mid-May, most were blooming by the end of March.
It began on a balmy, warm March 11 with coltsfoot, which flowered four days ahead of its earliest date back in 2000. As the month progressed, the gap between the previous earliest date for many wildflowers, shrubs, and even trees, such as shadbush, widened.
I couldn’t keep up with all the changes. Because of that, some of my dates were probably a day or two behind where they should have been. For instance, round-leaved violets are usually out a few days before hepaticas and trailing arbutus, but by the time I checked on the violets, the hepaticas and trailing arbutus had been blooming for at least five days, beginning on March 18. Rue anemone flowered on March 24, a full month ahead of the previous year, and at least two weeks ahead of any other year. The following day swamp buttercups, long-spurred violets, and purple trillium appeared also a month before any previous year. Red maples, spicebush, and shadbush blossomed by the third week in March and red-berried elder, wild black cherry, blackberry, and striped maple leafed out.
All of the previously mentioned plants, except coltsfoot, are natives. But the non-natives and invasives were also way ahead of schedule. Our crocuses were a week early. Forsythia, daffodils, and hyacinths bloomed in our yard by mid-March and privet, multiflora rose, Japanese barberry, and garlic mustard burst into leaf.
The incredible warmth lasted until March 26. Then we had what we had feared—a killing frost. Our several hundred daffodils flopped to the ground and the forsythia flowers wilted and never recovered. The leaves of privet and multiflora rose similarly went limp but not those of Japanese barberry. However, all of them eventually rallied except for some of the daffodils and the forsythia blossoms.
The natives stood up to the 22 degree Fahrenheit temperature and continued to open. Lowbush blueberries dangled their pink and white, bell-shaped flowers on the powerline right-of-way, common blue violets blanketed the path through Margaret’s Woods, and early saxifrage blossomed on the Far Field road bank. Not one early wildflower drooped.
But on March 29, when the temperature shot back up to 70 degrees, our pear trees bloomed. That’s when I began to seriously worry about our warm March. I knew a frost would kill the blossoms and the possibility of fruit in late summer. And that’s what happened on the thirtieth of March.
Throughout April, the temperature waxed and waned but the plants, once started, seemed unable to stop despite the colder days, and I continued to record record-breaking dates for all of them. In early summer the lowbush blueberry crop failed. In late summer there were no wild apples, pears, or wild black cherries for the wild creatures on our mountain, and in the fall there were few wild grapes or acorns. Our black walnut trees did produce a bumper crop probably because they are the latest of trees to leaf out and flower, but the hickory trees in the woods did not have any nuts.
Our local orchard in the valley didn’t fare well either. Although cooler April temperatures did slow down the blossoming of some trees, hard frosts near the end of April froze the cells of the new leaves and blossoms. Because of that, they had no apricots, sweet cherries, or pears, very few sour cherries and plums and half the usual crop of apples and peaches to sell. But they do grow several varieties of peaches and apples so the trees didn’t blossom all at once. Diversity, both in wild and domestic crops, was the key to withstanding, to some extent, the unusually warm March and cold April.
Apparently, keeping records of blooming dates for plants and the emergence or migration dates for insects and birds makes me an amateur phenologist or someone who studies phenology, which is defined as the study of the effects of seasons on plants and animals.
Phenology was studied as early as 974 B.C. by the Chinese, but it was the Swedish taxonomist Carolus Linnaeus, who lived from 1707 to 1778 and recorded flowering times for 18 locations in Sweden over many years, who shared the title “Father of Phenology” with Englishman Robert Marsham (1708-1797). Marsham kept systematic records of what he called “Indications of Spring.” From 1736 until 1796 on his country estate Stratton Strawless in Norfolk, England, Marsham recorded 27 signs of spring including the flowering dates of four species, the leafing dates for 13 tree species, the arrival and first songs of migrant birds, and signs of the breeding activity of rooks, frogs, and toads. His descendants kept up the tradition until 1958 when his last descendant, Mary Marsham, died.
Marsham was especially enamored of trees and planted thousands, most of which were cut down during the two world wars, but a giant cedar remains that he planted in 1747 as well as an avenue of ancient oaks.
He also corresponded with fellow Englishman, the Reverend Gilbert White, who kept similar records on which he based his seminal nature book The Natural History of Selbourne, published in 1789, which was accompanied by his The Naturalist’s Calendar. Thus began in England a tradition among amateur naturalists to keep phenological records that naturalists in other European countries imitated.
Here in the United States, naturalists, both amateur and professional, have kept such records, but most are buried in herbaria, museums, archives, and family papers. One researcher, Caitlin McDonough MacKenzie, is studying such information in the herbaria and archives of Acadia National Park in Maine. She hopes her research will track the ecological effects of climate change on plant communities over time.
More formally, The Lilac Network, funded by the United States Department of Agriculture, began in the late 1950s in the western United States. Using the non-native common purple lilac plant (Syringa vulgaris), volunteers recorded “first bloom,” “full bloom,” and “end of bloom” in an attempt to use phenology “to characterize seasonal weather patterns and improve predictions of crop yield,” according to their website.
In 1961 the central United States and in 1965 the northeastern United States joined in, and volunteers observed the cloned plants of the lilac cultivar Syringa chinensis “Red Rothomagensis” and added dates also for “first leaf” and “95% full leaf.”
Today, as climate change accelerates at an unprecedented rate, phenology is more important than ever. That’s why the National Ecological Observatory Network launched Project BudBurst in 2007. According to their website, “We are a network of people across the United States who monitor plants as the seasons change by timing the leafing, flowering, and fruiting of plants.” Thousands of folks from all 50 states—school groups, backyard naturalists, gardeners, seniors in retirement communities, scout groups, college professors and their students, hikers, botanists and ecologists, and visitors to botanic gardens, national parks and wildlife refuges—are producing data that scientists can use “to learn more about the responsiveness of individual plant species to changes in climate locally, regionally, and nationally.”
Their website has a list of targeted plants by state that volunteers can use. The plant groups include wildflowers and herbs, grasses, deciduous trees and shrubs, and conifers for Pennsylvania. Both natives and non-natives, even invasives like Japanese knotweed, are included. Under wildflowers and herbs are such plants as jack-in-the-pulpit, large-flowered trillium, mayapple, and Japanese knotweed. Deciduous includes forsythia, common lilac, shadbush, red maple and flowering dogwood, and conifers are eastern red cedar and eastern white pine. Volunteers can choose one or many plants to monitor using either the Project’s suggestions or plants of their own choice.
While I have been contributing to a variety of citizen science bird-related studies over the years, I have never been involved in submitting plant-related data. I have always hoped that my nature journals and records will be of value to researchers in the future, especially as our climate continues to change, so Project BudBurst looks like a program I can sign on to, and mayapple will probably be my chosen plant. We have several huge patches on our property. Last spring the first flowers opened on April 27 but the first bud appeared on April 18. The cold of April did hold back that wildflower more than most, but still it bloomed a full week ahead of time.
Project BudBurst sums up their mission statement in haiku form that they hope will inspire more people to volunteer:
People watching plants
Contributing to research
For more information on Project BudBurst, you can consult their excellent, informative website.
Photos by Dave Bonta (click for larger versions)