Lois Berg Stack, who worked for 30 years as an ornamental horticulture specialist, retired from the University of Maine Cooperative Extension in January.

I haven’t counted, but I think she is the source I have used most often since I began writing the Maine Gardener column in March 2004, whether I was attending lectures she gave around New England or calling her up to pick her brain. I had heard about her long before I started the column because my wife, Nancy, has been an active member of the Garden Club Federation of Maine for all of the 30 years Stack was with the Extension and always raved about Stack’s lectures.

I’ve held onto the notes from a 15-minute talk on New England’s indigenous fruiting trees and shrubs that Stack gave in February 2015 at New England Grows in Boston, thinking that if I ever had a week in which I couldn’t think of a column idea or if one requiring interviews fell through, I would use the notes for a back-up column.

The back story of the lecture is that New England Grows is a huge, usually three-day event for landscapers, nursery professionals, lawn guys, suppliers of granite, suppliers of anything to do with gardening and so on. That morning someone else was supposed to give this talk – I can’t remember who. But that was the winter Boston and New England Grows both got slammed with record-setting snow during the event. Stack filled in, smoothly and knowledgeably, as always.

After her talk, I asked how long she had to prepare. She said she organized the talk while walking the 100 yards from the New England Extension’s booth to the lecture hall lectern, which, she said, explained why the plants were arranged in roughly alphabetical order. She just pulled them out of the plant catalog that exists in her head – which would be a nice thing to have.

Now is a good time to make use of these notes, both because she is retiring and because I want to keep emphasizing how important native plants are to supporting native wildlife, which evolved along with these plants. All these indigenous fruiting trees and shrubs are hardy in all of Maine, Zones 3 to 6, with some even okay in Zone 2, which is a couple hundred miles north of Maine’s northern border. (For other Stack fans, I interviewed her just before she retired for a future column on plant names. Coming to you soon in this space.) Stack praised two native aronias, but favors Aronia melanocarpa, or black chokeberry, and hoped more people would begin growing it commercially.

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“Black chokeberry has more antioxidants than any other fruit I can think of,” she said. The problem is that the berries do not taste good if eaten raw, so they have to be made into juices or jams to be edible.

Both the black chokeberry and red chokeberry, Aronia arbutifolia, have attractive white flowers in the spring in addition to their berries; the black berries are larger and hold on longer in winter.

The plants are adaptable to many different soil types. They grow 8 to 10 feet tall and 6 feet wide.

Amelanchier, or serviceberry, is an excellent substitute for the non-native crabapples, Stack said.

“It gives us the same thing the crabapple does: flowers, fruit, fall color and architectural branches in winter,” she said.

The white flowers bloom in early spring, and the berries ripen in June and are tasty if you can get to them before the birds do. Amelanchier does well in wetlands but also grows in drier soil.

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American hornbeam is not usually included as a fruiting tree, but technically speaking it is, and Stack said she included it in her talk for its ornamental values. It grows about 22 feet tall, is multi-stemmed but classified as a tree, and tolerates a wide variety of soils.

The fruit arrives in late summer as what she described as “curiously bracted fruitlets,” with a leafy bract hanging over the tiny fruits, which are inedible except by birds. The bracts stay on the tree, and change from light green to yellow, while the leaves turn a reddish purple – providing an array of colors on one tree.

The Cockspur hawthorn, Crataegus crusgalli, is a thornless version of a native hawthorn, so this is the one you want if children are going to be playing nearby. Hawthorn thorns, which can be attractive in winter and protect the fruit, can grow as much as 4 inches long. It is a small tree, reaching about 25 feet tall, with spreading branches making it about 30 feet wide. It flowers profusely in May or June and produces small fruit that is edible but mealy. The fruit persists during winter and is a great forage plant.

The beach plum and sand cherry, Prunus maritima and Prunus pumila, are two related plants that offer terrific flowers that pollinators love.

“When they are in bloom it looks like the plant is moving because there will be thousands of pollinators on a single plant,” Stack said.

If you want fruit in addition to the blossoms, you will need more than one prunus plant that bloom at the same time, so they can cross-pollinate. In addition, all of the native plum family get a black knot fungus, but she said you can prune it out without much trouble.

Vacciniums, which include high-bush and low-bush blueberries as well as cranberries, have white blossoms in the spring and delicious fruit in August. Everybody should grow several in their yards both for the delicious fruit and for the spring blooms and brilliant fall foliage.

New England Grows has changed its meeting dates to the beginning of December. I doubt that the date change is due to the blizzards in Boston in March in recent years. Heaven knows who will be staffing the New England booth instead of Lois. She will be missed.

Tom Atwell is a freelance writer gardening in Cape Elizabeth. He can be contacted at 767-2297 or at: tomatwell@me.com.