Dieter Trost Jr. of Southern Oregon Nursery waters a dwarf birch in Trost. [Jamie Lusch / Mail Tribune]

Dieter Trost of Southern Oregon Nursery discovered the Trost dwarf birch in 1976. [Courtesy photo]

You might remember a margarine ad from the 1970s, featuring an elderly woman in a white dress and a wreath of daisies. Said she tastes margarine not butter, she says threateningly, “It’s not nice to cheat on Mother Nature”, and wreaks havoc with rain, lightning and, yes, elephants. (those crazy people from the 70s).

Yet Mother Nature has no problem fooling us, whether it’s desert mirages, green flashes, or, for the locals, the Oregon Vortex. Fortunately, some of us humans have a few cards up our sleeve as well.

This was the case in Medford one fine day 45 years ago, when Mother Nature solved a riddle about Dieter Trost, an amazing nurseryman and owner of Southern Oregon Nursery. In 1976, he came across a bunch of finely dissected, broom-shaped leaves growing on part of a European birch. It was a “sport,” a horticultural term for a plant that produces a branch very different from the host plant.

Trost knew he was on to something. He was a second generation nurseryman (the southern Oregon nursery is now in its fourth generation.) So Dieter propagated the cuttings, now sold as Betula pendula ‘Trost’s Dwarf’ (as well as many other common names).

It is an amazing plant that must be seen to be truly appreciated. A favorite of bonsai growers, it is also ideal for rock gardens, which are increasingly popular amid these seasons of drought and climate change. It takes almost a decade for the beige bark to turn into the classic white birch. It’s as wide as it is tall, reaching 3-4 feet tall and 3 feet around, so it’s also great for topiaries.

The Trost Birch has some interesting tips that are suitable for such a wonderful sport. For example, when you see it for the first time, you might think that it is a Japanese maple, even though it is beautiful. Only by looking closely, under the leaves, will you realize that it is indeed a birch.

Another fascinating aspect is the special nature of the leaves. They grow to about four centimeters long and three centimeters wide. The doubly serrated leaves adorn the plant like lace.

But perhaps the most interesting thing is that due to its extraordinary light green pigment the leaves can appear semi-transparent, wispy and pellucid under natural sunlight … that is, the leaves can appear semi-transparent, wispy, and pellucid under natural sunlight … leaves let in the light but not the detailed shapes, so another trick, that of the eye.

“It was a wonderful find,” enthuses Baldassare Mineo, former owner of the rare plant nursery Siskiyou, which has now been “displayed” in Italio Gardens at 2825 Cummings Lane in Medford.

“It’s just a sensational introduction.” said Mineo. “To see it is to want it. … “It’s an elegant habit that rivals and mimics the most beautiful leaf shapes of Japan.”

Another advantage is that despite its filigree and delicate appearance, it is resistant to deer and drought. It is also more resistant to insects, such as borers, than many other birch trees.

Dieter Trost Jr., one of Trost’s two sons, recently took a tour of the nursery to show off the eponymous plants – he had two in stock. He speculates that the sport arose because of pollen dropped by a bee or bird, but he’s really not sure, which adds to the mystery.

Birch was listed in the United States National Arboretum in 1984 and is popular with garden enthusiasts, which is ideal for southern Oregon, which has a rich collection of gardeners who appreciate Trost’s birch. It is available online and at Southern Oregon Nursery. Trost Jr. says they regularly sell about 15 dwarf trees a year.

“It can be a difficult plant because of the roots,” says Trost Jr. He explains that birches are naturally attracted to water, but this particular hybrid needs good drainage because overwatering “causes rot. roots”.

Dieter Trost died at home in November 2020 at the age of 84. His parents established Southern Oregon Nursery in 1945, and Dieter became part owner in 1955 and owner in 1963, and the business is still a family business today.

He is survived by his wife Judy, his sons Dennis Trost (Carie) and Dieter Trost, Jr. (Tammi); six grandchildren and one great-grandchild, Andrew (Kori), Alexa, (son, John), Callen, Ben, Emma and Matt.

In addition to seeing the trees in the Southern Oregon Nursery and Italio Gardens and Nursery, a variety of Begula Pendula (v. Lacianata) grows at Station 73 on the Self-Guided Tour of Lithia Park.

The Lithia Park Trail Guide offers colorful maps, over 100 photographs, and a self-guided tour. The tour starts at the entrance to the park and is a great way to wander around on your own and see the plants that the park has to offer. You can download and print a copy of the guide at www.ashland.or.us/Files/LithiaParkGuide_Digital.pdf

Jefferson Reeder is a freelance writer in Medford. He can be reached at treederyay@gmail.com.