For Going Green
What do birds need to thrive? And does it matter if the plants in our yards are native to the East Coast?
Those were the questions Dr. Desiree L. Narango asked for her Ph.D. research — and she learned some startling things. She focused on just one bird, the chickadee, in the D.C. Metro area. She found that over two-thirds of the vegetation in the area needs to be native plants to maintain their population, and 90 percent of the vegetation needs to be native for chickadees to thrive and expand their numbers.
So why is this? And can bird feeders make up the difference?
If you have ever watched a bird that has a nest in your yard, you have undoubtedly seen a lot of activity of the parents carrying wriggling stuff to feed their hungry brood. Narango discovered that the parents deliver over 350 protein-rich insects and caterpillars to their nests in one day. So where do they find these caterpillars?
In Massachusetts, there are over 2,000 caterpillar species. They are part of the life cycle of moths and butterflies, who lay their eggs on plants that their caterpillar offspring eat to grow. So, a new question — what enables moths and butterflies to thrive?
Narango’s Ph.D. thesis professor, Doug Tallamy, and his Ph.D. students, have been exploring this question for several decades. They have found that most moths and butterflies are very choosy about where they lay their eggs. One quarter of them lay their eggs on one plant species … like the monarch choosing milkweed. Three quarters of them use only five plants or less. And most of the plants they use are native to our area.
When you Google “Native Plant Finder,” created by the National Wildlife Federation, you can find data about trees, shrubs, moths and butterflies. For example, I found that over 250 species lay their eggs on sugar maples. Tallamy also found that only seven species lay their eggs on a Norway maple. One Norway maple is no big deal, but when 50 percent of the street trees are Norway maples, as they are in Greenfield, that is something to think about.
The good news is our yards make up half of the green space in cities, and insects love forest edges like our yards — so there is much we can do! And it is important to do something because surprisingly, one fifth of U.S. land is urban or suburban.
Last year, Greening Greenfield launched a campaign called Planting for Pollinators.
Let’s build biodiversity and beauty in the Pioneer Valley. We have been learning a lot, not only about what to plant, but also how to avoid buying flowering plants that have neonics in the soil, which make them toxic to the very insects we want to support — not just to pollinators but also to caterpillars.
Our campaign has a web page with resources about where you can buy native, clean, (neonic-free) plants, and much more.
For the past 30 years I’ve been having fun replacing non-native trees and shrubs in my yard, one at a time. I’ve also kept some plants from other countries that evoke fond memories, and I have things like pears, tomatoes etc. that I want to eat.
One lesson I learned along the way, was to be cautious about what you buy. For example, I bought a birch tree, assuming it was native, only to find out 20-years later that it is a European species. That is why I like to buy plants from Nasami Farm in Whately because all of their plants are native and clean.
Nasami Farm is where the New England Wildflower Society grows its plants. Recently, it changed its name to Native Plant Trust to reflect the new understanding that it takes trees, shrubs, and flowers for our butterflies, bees, and birds to thrive! I also like that they grow plants mostly from seed collected in our region, rather than from cuttings. This takes longer, but it preserves the genetic diversity of our landscapes. There are also several small growers that offer clean native plants in our area that are listed on our web site.
If you’d like to learn more, please check out our Planting for Pollinators campaign web page for resources and to watch for our fall speakers on how to put your garden to bed and support pollinator as well as planting trees, shrubs and more in the fall. Go to http://www.GreeingGreenfieldMA.org and click on Take Action. Together, we can build healthy habitat and beauty.
Nancy Hazard is a member of Greening Greenfield’s Planting for Pollinators and the Greenfield Tree Committee. She can be reached at Nancy.Hazard@worldsustain.net