Dogwood Lane

The Quarterly Journal of the Mary May Binney Wakefield Arboretum ___________________________________

Volume Two, Issue 3 - Spring 2020
Perpetuating the Age-Old and Important Impulse to Collect Plants
Due to the coronavirus, this spring has been like no other in our lifetimes. We have been forced to stay in our homes away from friends, family members, jobs and play, trying to make sense of all that is happening. Many of us are fortunate enough to take comfort in the things that surround us: our families, favorite books, music, pets, recipes and objects. Beginning with hunter gatherers, humans have been collectors of things, living and non-living. Working at the Mary May Binney Wakefield Arboretum has given us all the opportunity to meet people that are collectors and admirers of plants.

Polly Wakefield and her family were collectors of many things over the generations including art, books, travel memorabilia, minerals and plants just to name a few. Polly loved growing and collecting plants and books about plants. She left behind her own comprehensive library of plant and garden design books and provided the Arnold Arboretum library with an important bequest because she loved books and perhaps saw a window to the future where they might be lost. Polly’s plant collection is what makes our arboretum a special place. Her interest was in having not only a collection of Cornus kousa dogwoods but also a large collection of species from many families and genera. This quarterly issue focuses on plant collecting-- whether it is a serious hobbyist like Polly, or a professional plant hunter working for an arboretum traveling all over the world collecting for genetic diversity, they all have one thing in common: their love of bringing a collection of plants for both personal and public pleasure.
Collecting for the future - by Deb Merriam
When I joined the American Conifer Society as a representative of the Mary May Binney Wakefield Arboretum, I noticed that its members, self-described “coneheads,” shared one common trait: the joy of collecting conifers.
Plant collecting has played a seminal role in human development, so why not conifers? Collectors range from amateurs looking to enhance their home gardens with these gymnosperms, to trained landscape designers and horticulturalists showcasing them to clients, and to botanic gardens that collect them for research in protecting biodiversity. The following article focuses on Polly Wakefield’s interest as a committed amateur collector and propagator and the Arnold Arboretum’s ten year plan to collect to protect plant species for future generations.
Polly Wakefield: innovative plant collector and propagator
Polly Wakefield, a trained landscape architect and plant propagator, began her love affair with plant collecting in 1956 when she started taking classes with Roger Coggershall at the Arnold Arboretum. Each year, participants in Roger’s propagation class were given the choice of selecting seed from one tree in the collection. Polly wrote: “At the summit of Bussey Hill was a group of Korean dogwoods ( Cornus kousa) . I chose one that had large fruit. Over the next 34 years, I collected fruit from this tree and two other dogwoods at the Arboretum.”

Polly loved kousas because each tree has unique bark, bracts, fruit, and leaves. She ended up selecting and patenting seven cultivars of Cornus kousa after planting more than 600 on her property. Her interests in plant propagation and developing a collection grew far beyond Cornus to include a wide variety of conifers. Because she enjoyed trees with unusual bark, she collected Pinus bungeana (lacebark pine), S ciadopitys verticillata (Japanese umbrella pine), Cryptomeria japonica (Japanese cedar), and Chamaecyparis pisifera (Sawara false-cypress), all originating from seeds, cuttings, or grafts from the Arnold’s collections.
Polly Wakefield, at center in blue, during an Arnold Arboretum walk with Dr. Donald Wyman.
She also developed an interest in dwarf conifers from her experiences at the Arnold while working with Al Fordham, arboretum propagator, and Donald Wyman, arboretum horticulturalist. Al Fordham wrote extensively for Arnoldia about conifers and dwarf conifers. He was a leading expert on the propagation of gymnosperms and published the Propagation Manual of Selected Gymnosperms. His expertise in woody plant propagation was acknowledged throughout the country, and his advice was sought by colleagues, both here and abroad. After learning from these two men, Polly created a small garden of semi-dwarf pines and Japanese maples in 1990 and named it “The Witches’ Garden”. Today the 30-year-old, semi-dwarf pines have outgrown their space and are being shaded out by Acer palmatum (Japanese maple). Careful restoration of healthy pines and the removal of dying ones are allowing the garden to survive for a few more years before a more drastic renovation will have to take place.
Garden in transition
Polly Wakefield passed away in 2004 and left her property in a private trust to be used for education and community engagement. Her garden had not been maintained for 10 years prior to her death. Heavy deer browsing had led to the severe decline of old, massive Taxus (yew) hedges and much of the woody understory. In 2012, a landscape management plan was put into place, beginning with the installation of deer fencing. Five acres of the formal gardens were fenced in to protect newly planted specimens and old, severely damaged yet salvageable, yew hedges. Since that time, many of the plants in the landscape have been rejuvenated, and new ones have been added.
In order to highlight Polly’s interest in dwarf conifers, a brand new conifer garden was created within the collection. This garden tackles a difficult site on the property, highlights her love for unusual conifers, and continues Polly’s legacy of developing unique garden spaces in her landscape. Because many of our visitors have small
gardens in urban areas, the garden also features many varieties of conifers with colors, textures, and winter interest suitable for small urban spaces. We implemented an ambitious plan that included a new drainage system, soil remediation, hardscape repairs, and interpretive signage. Staff and volunteers worked more than 400 hours on the project. The plan was completed over a three-year period and contained plants from Broken Arrow and Iseli nurseries. This garden is now a Reference Garden for the American Conifer Society and is used for conifer-focused workshops throughout the year.
Collecting for the Arnold Arboretum: a Ten year endeavor
An Interview with Sean Halloran, Arnold Arboretum plant collector
Sean was interviewed about his experiences and the role he plays in the Arnold’s ambitious Living Collections 10-year project.

Sean, can you tell us a bit about your background and how long you have been at the Arnold Arboretum?
I started at the Arnold in 2016, and, before this amazing opportunity, I managed a gardening company out of Cambridge, MA, which focused on private residential horticulture. That job was incredible because it was really the practical landscape experience every horticulturist needs to make what we do all the more meaningful. It is very fast-paced, creative, and fun work. Prior to that, I worked in greenhouse and nursery crop research for Fafard, a soil-less media company. Before that, I was a graduate student in tissue culture at Clemson University, SC. My undergraduate degree in horticulture is also from Clemson. I feel lucky that I acquired a well-rounded view of our industry due to these various experiences.

Tell us about the Arboretum’s goals for the 10-year project.
The Campaign for the Living Collections is a 10-year effort to target nearly 400 species of woody plants that represent different goals for the Arnold Arboretum’s collections. With this project, we hope to further plant conservation and, more specifically, to increase genetic diversity in cultivation.
What role do you see yourself and other greenhouse staff members playing in this work?
Our role is an important one. We are vital in ensuring that seeds become trees. We accomplish this by doing the research and hard work inherent in cultivating species that are difficult or even new to cultivation. Not only do we grow the seeds, cuttings, and scions that we acquire, but we also seek to ensure the long-term survival of lineages. We do this by propagating existing lineages that are threatened in some way.
 
What are some of the biggest challenges in projects like this?
From the production and propagation side of things, the biggest challenge for us right now is space. We are a small facility with four propagation-style greenhouses and approximately an acre of nursery space. Since we won’t be expanding any time soon, the challenge is how do we shoehorn 400+ new accessions into the space that we have? We are solving this by getting creative with our nursery space, growing more plants in containers, and being very selective about what we grow and what we give away to other institutions.
Tell us about the process of arranging a collecting trip.
 In planning a plant collecting expedition, there are legal, logistical, and even ethical questions to be answered. To give you an example, our most recent trip in September 2019 was three weeks long. We made 100 collections in the wild, and we spent nearly four months planning every detail. Most of this planning time is typically spent making the right local contacts and waiting for permits. The local experts are critical, whether they are in plant conservation, local, or federal government, affiliated with a local university, staff at gardens, or hobbyist botanists, or plant collectors. These are the people who provide the access to land, obtain required permits to collect seeds and herbarium vouchers, know the locations of populations of desired taxa, or can provide useful insights into land use, history, and context of specific sites.

How do you decide what are the taxa of interest?
Our recent trip to the Southeastern U.S. was to a broad geographic area, and there were many institutions involved. Essentially, we wanted to be fair to all institutions involved, obtain taxa of value for both conservation and collection efforts, and do the most good by the plants, ecosystems, and people involved. For example, we won’t collect a taxon when a population is so limited that in situ conservation would be more valuable. Those are the kinds of decisions that have to be made both as part of our planning and in the field.

Tell us about interests of plant collectors from Asia vs. those from the United States.
It is easy for us in North America to forget the treasures we have here, especially in woody plants, when we consider the diversity and number of species endemic to Asia. With that said, plant nerds are plant nerds, no matter where they live! On our recent trip with Chinese colleagues, everyone on the trip had a unique perspective and bent towards that which attracted them. We were all able to learn from each other’s varied experiences and interests.

You wrote an article after collecting in the Carolinas about the importance of understanding the habitat type, in which a certain species grows. Can you talk about that using the example of Pinus palustris ?
That is a great example. The longleaf pine savanna in the American southeast, dominated by Pinus palustris (longleaf pine), is an incredible ecosystem. This habitat type used to cover roughly 60 million acres and is now down to less than three million acres. The name “savanna” might lead one to envision a plain dominated by grasses and maybe a few trees, but longleaf pine savannas are among the most diverse ecosystems in North America. When looking for certain species that are known associates, it is important to consider the distribution of ecosystems like longleaf pine savannas when starting your collection trip.

We are grateful to Sean for taking time out to conduct this intriguing interview with us!
Thanks, Sean - and our thanks to those who provided the lovely photos that accompanied this piece.
Planting trees for the environment
As we recently celebrated the 50th anniversary of Earth Day, people joined together all over the world to plant trees. Forests are one of our most powerful tools to combat climate change and provide food and habitat for the species of the world. Trees filter the air and stave off the effects of climate change by removing carbon from the atmosphere through a process called sequestration. Trees also reverse the impacts of land degradation and provide food, energy and income to communities. At the Mary May Binney Wakefield Arboretum, we decided to celebrate the 50th anniversary of Earth day by reforesting an area in our woodlands that had been overrun by invasive species for many years.
Over the past three years, staff removed invasive species and dead trees in a 5 acre woodland that consists of red maple, pine and cedars. Many of the trees had been strangled to death by invasive vines. Once these species and dead trees were removed native flowers began to thrive including blood root ( Sanguinaria canadensis ,) Jack in the pulpit ( Arisaema triphyllum ,) skunk cabbage ( Symplocarpus foetidus) and spice bush ( Lindera benzoin ).
Once the invasive species have been removed the most important part of renovating a woodland is to fill the empty space with native plants. Staff members planted red maples and serviceberry. The area has been surrounded with a temporary deer fence to deter deer from nibbling on and rubbing their antlers on the new plantings.
Database project during the Coronavirus lockdown
Following the recommendation to shelter in place due to Covid 19, the Mary May Binney Wakefield Arboretum partnered with 28 Master Gardener volunteers to complete a plant collections database project. Plants that had been geolocated using Google earth needed to have documentation and information added to each individual specimen. Tucker Smith and Megan Sekhar, our gardener liaisons with Massachusetts Masters Gardeners, summoned the volunteers to a stay at home action. Each volunteer was given a list of ten plants to research using a list of reliable sources, including botanical garden websites and well regarded collection books such as Michael Dirr's Manual of Woody Landscape Plants . A form was filled out with details of the each plant's origin, its characteristics and habits and any interesting tidbits. The data was collected by Debbie Merriam and entered into Plants Map database with the help of Master Gardener Kathy Webster. The result is up for all to see via this link .
Thank you to everyone who helped in this project!
Losing Two Giants from the Arboretum's Collection
The Canadian or Eastern hemlock ( Tsuga canadensis ) is one of the most beautiful and stately trees growing in the Eastern United States. However, they are becoming more rare due to the impacts of Hemlock Woolly Adelgid, an invasive pest that has devastated huge stands of these giants. Hemlocks can live up to 900 years and provide a unique ecosystem that cools streams and valleys for a vast network of animals and plants. In mid March a wind storm that brought 80 mile per hour winds to Milton took down two of our oldest hemlocks. These giants, that pre-dated the Civil War, survived the 1938 hurricane which devastated many of the large trees on the property, and continued to thrive until that day in March. 
The amazing thing about collecting things that are alive is that we can watch them evolve over time, provide great enjoyment and beauty with their subtle or not so subtle changes — but we know that one day these plants will succumb to storms, drought or senescence and in their place a new plant will grow. Hemlocks have the unique ability to “wait in the wings” for sunlight. A baby hemlock tree can survive for hundreds of years in the shade of giants by growing extremely slowly until one day the large hemlocks are blown over in a storm or come to some other end. The slow growing hemlock then has the sunlight it needs to thrive and dominate the growing space left by the fallen giant. We are hopeful that some young hemlocks planted or “waiting in the wings” may take the place of the giants and much like Polly Wakefield, the staff will watch over them and make sure they grow tall and strong.
Postscript: In order to prolong the "life" and value of these magnificent trees, we kept the stumps of both felled hemlocks and a long segment of the healthier tree's trunk. They will be pleasant resting spots for quiet contemplation. Also, in our educational programs, we will be sharing the amazing history of the trees by counting the rings and comparing them with moments in world history. Can you count the rings?
Articles written By Debbie Merriam
Edits By Mark Smith and Erica Max
Layout by Erica Max
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