Right in Our Backyard

Fending Off the Invasive Garlic Mustard

By Bill Lawyer

Some readers might think it’s a sacrilege to write about garlic mustard in The Rye Record’s annual garden issue. Many people feel the same way about phragmites.

But so many home and professional gardeners are fighting what seems to be a losing battle against garlic mustard — a pretty, unobtrusive, springtime flowering plant.

Why? Because garlic mustard plants are the epitome of invasive plants that were brought to North America by European colonists. The European immigrants’ ancestors had been using it since at least 4,000 B.C.

And back then, it was for clearly obvious reasons that garlic mustard was seen as a good thing.

The name “garlic mustard” is a very succinct way of highlighting two of the many ways that the plant has been used. This includes seasonings, greens for salads and sauces, and much more, according to Simon & Schuster’s “Guide to Herbs and Spices”. The garlic flavor is where its gets its genus name, <Alliaria>.

Not only that, but it is widely known as being a source of vitamins A and C, and it has medicinal properties as well.

I first became aware of garlic mustard back in the 1970s, when my Greenburgh Nature Center staff and I put together an exhibit, “Green Immigrants”, about plants that had arrived from overseas and their useful attributes.

We were inspired in our endeavor by the book “Green Immigrants: The Plants that Transformed America” by Claire Shaver Haughton, which was published in 1978.

Back in those days the emphasis on plant study was finding what they could be used for, and there was a sense of optimism about the direction plant specialists were going. The people who brought plants to the U.S. from around the world in the “Darwin Days” of the 19^th century were hailed as heroes.

Our exhibit consisted of artistically pressed and framed flowers of about 30 of the plants covered in the book.

Garlic mustard is an herbaceous biennial, meaning it has a two-year life span. In the first year it produces low-to-the-ground leaves, and it comes back the following spring in the flowering phase. Each plant produces hundreds of seeds — and can even produce seeds without pollination.

These are modest plants with cheerful, cross-shaped flowers. I can recall my kids in their younger days picking bouquets of garlic mustard greens and flowers as we walked along woodland trails. Right now, you can see them blooming on the Blind Brook path from Milton Cemetery to Oakland Beach Avenue.

While some imported plants can blend seamlessly into the woodland ecosystems, mustard garlic has a few characteristics that made it go from a good guy to a bad guy in environmental circles.

Field research reported that there were very few natural predators of garlic mustard, which has resulted in the disappearance of many plants that preserved the diversity of the region’s forest floors. Deer do not like garlic mustard.

Right now, the main approach is for volunteers or paid staff members to carry out periodic blitzes to stop the spread of the plants to wider, less easy to manage territories.

It’s sadly ironic that through no fault of its own it became an anathema in northeastern America.

The hope is, as happened to gypsy moths, some new predator can be found to help turn this depressing trend around — right in our backyards.