This past long weekend, we traveled across Massachusetts into the heart of autumn. Along the way, I introduced Marjorie to old friends.

Our first stop on Saturday was Mount Auburn Cemetery in Cambridge, one of our country’s most significant cultural landscapes. And with more than 5,000 trees representing more than 600 taxa, Mount Auburn is an arboretum of national importance.

It is impossible to separate the historical and botanical aspects of this sacred place. One minute we were marveling at the size and beauty of a Japanese katsura tree, Cerdidiphyllum japonicum, or the fluorescent colors of a broad-spreading sugar maple; the next moment we were standing in awe before the simple gravestone of Oliver Wendell Holmes or the lichen-patched monument of botanist Asa Gray. Henry W. Longfellow and Amy Lowell are buried at Mount Auburn, along with Bernard Malamud, Felix Frankfurter, Buckminster Fuller, Homer Winslow, and other men and women who shaped the history of our country.

Here too grow champion trees. Massachusetts state champions include a paperbark maple, Acer griseum; flowering dogwood, Cornus kousa; and yellowwood, Cladrastus lutea, while New England champions are represented by a Sargent cherry, Prunus sargentii, and a sawtooth oak, Quercus acutissima, among others.

I last saw the trees of Mount Auburn with a group of UMaine horticulture students, my Woody Plants Identification class of 2002. This autumn, strolling slowly along the narrow paths, I introduced Marjorie to old friends, to the weeping European beeches, Fagus sylvatica ‘Pendula,’ their elephant-hide trunks hidden behind curtains of pendulous branches; to the Amur corktrees, Phellodendron amurense, with thick, cork-ridged trunks and bright yellow leaves; and to the dawn redwoods, Metasequoia glyptostroboides, growing at the edge of Auburn Lake, their flaring trunks sending long, horizontal branches out over the water.

From Mount Auburn we journeyed west to Northampton for a brief stroll at dusk through the Smith College campus. Old friends from my teaching days at UMass Amherst are still growing there, including a ginkgo tree, Ginkgo biloba, planted in 1901, now 50 feet tall and wide. Although its fan-shaped leaves were still dark green, I remembered it from another autumn, a million golden leaves shimmering on a blue-sky October afternoon and then the ground beneath it carpeted in gold the next morning It is the way of ginkgos to drop all of their leaves at once.

We spent Saturday night at Marjorie’s childhood home in Pittsfield, and on Sunday morning her mother, Joan, joined us for a drive to Williamstown and the campus of Williams College. We drove through the Berkshires at the peak of autumn, passing small farms nestled among hills painted red, orange and yellow.

The golden-orange and yellow leaves of sugar maple dominated the campus landscape, along with the soft yellow and apricot leaves of Japanese katsuras. Virginia sweetspire, Itea virginica, the cultivar ‘Henry’s Garnet,’ a 2-foot-high shrub with ruby-red fall foliage, covered the ground of several street-corner beds.

Our horticultural adventure ended Monday with a brief tour of Tower Hill Botanical Garden in Boyleston, a 30-minute detour off the highway home. Again, old friends, trees that I had not seen in 10 years, greeted us.

Children ran circles around an old sugar maple in front of the orangerie as we walked around the lawn garden, beds filled with the tarnished-brass foliage of summersweet clethra, Clethra alnifolia, and golden-leaved witchhazels, Hamamelis virginiana, in bloom, each flower a cluster of bright yellow ribbons.

Added to the collection since my last visit were three plants of winterberry holly with yellow berries, Ilex verticillata ‘Chrysocarpa,’ a mutation selected from the native red-fruited species. We were told that the yellow fruits did not survive extreme cold as well as the red.

Three days and 300 photographs later, we were back in Maine, back at work, dreaming of a spring trip into the heart of New England horticulture.

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