beach plum

Picture this: dense, twiggy colonies of dark, gnarled branches buried in sand along the barrier dunes of Lambert’s Cove Beach. What is this tough plant that thrives in such a challenging environment? The answer is obvious each May when these same branches erupt with beautiful white flowers. It’s our native beach plum (Prunus maritima). This exceptional spring display lasts a few weeks then something even better follows. Over the following months plump, tasty fruits ripen, often creating a bountiful crop for harvest by the end of the summer.

northern bayberry

My Vineyard hikes take me to many beautiful sites. I enjoy seeing the diversity of landscapes, many influenced by their agricultural past. A frequent plant I encounter in abandoned farm fields is northern bayberry (Myrica pensylvanica, now Morella pensylvanica). Quick to reclaim open pastureland, the shrubs have the unique ability to fix their own atmospheric nitrogen through specialized structures called root nodules. The nodules contain the nitrogen-fixing bacteria Frankia. This mutually beneficial symbiotic relationship allows bayberry to grow in soils with low fertility.

white oak

I noticed the oaks right away. My first visit to the Vineyard was in spring 2002 when the abundant oak trees were raining down yellow pollen. Later, after moving to the Island while my daughter was playing at the West Tisbury School playground, I wandered off into the woods to look at the trees. I was gleeful to discover five oak species, including Quercus alba, the white oak. A young mother asked why I was so excited. After I explained my love affair with oaks, and my new position at the arboretum, she gave me some input: “I hate oaks; they’re everywhere.


Big, blue snowballs of hydrangeas backed by a white picket fence are a summer staple on the Vineyard. While the mophead flowers of bigleaf hydrangea (Hydrangea macrophylla) are the most popular with tourists, there is a whole world of hydrangeas for gardeners to explore. On a seed-collecting expedition to Japan in 2005, I encountered three other hydrangea species that are valuable ornamentals: the panicle hydrangea, (Hydrangea paniculata), the mountain hydrangea (Hydrangea serrata), and involucre hydrangea (Hydrangea involucrata).


There are many good reasons for growing native plants. Native plants are adapted to local growing conditions, they promote biodiversity and support local wildlife, and in general they need less maintenance. Besides, native plants are Vineyard vernacular — they just look right in our gardens and landscapes.

The Polly Hill Arboretum’s herbarium collection began in 2001, with a gift of algae specimens from Island resident and seaweed expert, the late Rose Treat. A herbarium is a scientific resource consisting primarily of a collection of dried, pressed plant specimens. Herbarium specimens record the past and provide users with the historic and current locations of plants over time.