Arbor Day is celebrated on different dates throughout the U.S. due to climate differences. For Georgia it is the third Friday in February – this will be February 17th in 2012. National Arbor Day gets a lot of attention in late April, but in Georgia it is better to plant trees much earlier when trees are dormant, temperatures are cool, and winter rains are possible.
With Arbor Day coming up this week, I’d like to talk about the following three points:
-
Why it’s important to plant trees
-
Why it’s important to plant native trees
-
Why some native trees might be a better choice than others
Importance of planting trees
When my kids were in elementary school I would organize an Arbor Day event on behalf of the PTA. Most years we gave out seedlings that we purchased from the Georgia Forestry Commission. The kids loved the event, and the older ones could easily answer the question about what benefits do trees provide: Oxygen, shade, food for us and wildlife, shelter for wildlife, beauty, and protection against soil erosion. They also provide wind breaks, and they can provide privacy.
Why native trees
So you might think that it doesn’t matter what kind of tree you plant, but it does matter. Native trees support native insects and so they also support the creatures that rely on those insects – the whole local ecosystem has grown up around native trees and it depends on them. There are insects whose larval form feed exclusively on a plant or group of plants – insects such as the eastern tiger swallowtail butterfly (Papilio glaucus). Eggs are laid on the leaves of wild black cherry (Prunus serotina) and tuliptree (Liriodendron tulipifera); the caterpillars that hatch will consume a small amount of the overall foliage. Choosing to plant a non-native tree instead reduces the biomass available for specialized insects, resulting in fewer insects overall. There are studies that show that specialized native insects (most of what we have) cannot adapt to eat non-native plants. Fewer insects equals less food available for the birds that feed these caterpillars to their chicks.
 |
Why some native trees are better choices
In the paragraph above I talked about why choose a native tree over a non-native one. Now I'll like to talk about why choose particular native trees rather than just "any" native tree. Think "native" on a smaller scale - the environments in which you live need the indigenous plants that support them. For example, growing blue spruce (Picea pungens) in north Georgia adds nothing to the local environment - it is as alien to the insects that live here as a plant from Europe because it is native to the western United States.
Consider also diversity when choosing a tree. If your area is full of oak trees, consider planting something else instead of another oak. Doug Tallamy, entomologist and author of Bringing Nature Home, has created a top twenty list of woody plants (and perennials) for the mid-Atlantic region. This list is based on the number of different species of Lepidoptera they support - those caterpillars that the birds love to eat! While oaks are first on the list, adding a hickory (Carya sp.) or birch (Betula sp.) to your yard would allow you to support much more biodiversity.
Take a survey of not only your yard but the areas around you to see what native trees are already there. But don't that list stop you from indulging in something you love like the iconic flowering dogwood (Cornus florida) or the early flowering redbud (Cercis canadensis). If you want to attract more birds to your yard with fruiting trees then consider serviceberry (Amelanchier sp.) and hawthorn (Crataegus sp.).
So when Arbor Day comes this Friday, consider planting a tree for all the right reasons. And if you have kids or grandkids, be sure to involve them and talk about the reasons that we plant trees and conserve them.
|
Eastern tiger swallowtail butterfly (Papilio glaucus)
|
The grey days of January can be a discouraging time for the gardener. The once bright and crisp leaves of fall have faded to brown and lie crushed and torn on the ground, belittled by winter rains, freezing temperatures, and time itself. Deciduous tree limbs are bare, and perennial flower stalks rattle in the wind, their seeds mostly gone now. Native plants need this time to develop their roots and resources. But in Georgia, if we look hard enough, we can still spot the promise of spring.
Last weekend I spied my first Hepatica americana bloom (now Hepatica nobilis var. obtusa) – right on schedule. I was sorry to note that this was the second bloom, the first had already faded and was forming a seed capsule. I went walking to see what else I could find.
|
Hepatica nobilis var. obtusa
|
As my feet moved along the path, the decomposing leaves fluttered to the side, revealing the grey-green foliage of Pussytoes (Antennaria plantaginifolia). These and other semi-evergreen plants like fairywand (Chamaelirium luteum) and green and gold (Chrysogonum virginianum) patiently tolerate the loose leaf cover; if you look closely, you can see the buds of new leaves already formed, waiting for the longer days and warmth of spring.
|
Antennaria plantaginifolia
|
Hexastylis arifolia
|
Evergreen gingers like Heartleaf (Hexastylis arifolia) and Shuttleworth (H. shuttleworthii) are getting the last bit of use out of their leaves. New leaves will replace these fading ones which are a bit tattered and droopy now. As spring gets closer, sometimes I pull away the leaf duff to see if the flowers are visible yet. It’s a demonstration of my impatience – I love the hidden flowers of our native gingers. Perhaps I should keep a journal to remember which day they will bloom.
As I make my way around the back of the house I notice that elderberry leaves (Sambucus nigra ssp. canadensis) are emerging already along the pale stems. One of my St. John’s wort species also has tiny new leaves already. The blue-green foliage of the columbine (Aquilegia canadensis) soaks up the sun; it never really disappears either. Above it, the flower buds on the blueberries (Vaccinium sp.) are plump in expectation of flowering in the next month or so; their flowers are some of the earliest, timed to nourish the bumblebees emerging from hibernation.
|
Blueberry (Vaccinium sp.)
|
Wax myrtle (Morella cerifera)
|
I see the berries are ripening on the wax myrtle (Morella cerifera) – turning a beautiful shade of blue-grey. Juniper berries (Juniperus virginiana) are ready for the birds that love them - birds like cedar waxwings, bluebirds, and robins. And while I was looking at the berries, I saw that the new cones are forming on the juniper, no different than the flower buds already waiting on the tips of the dogwood (Cornus florida) branches.
|
Juniper cones (Juniperus virginiana)
|
.jpg)
Dogwood (Cornus florida)
|
And on the deck, stashed in rows of 1 gallon pots, is one of my favorite promises: the tender foliage emerging from the seed of a red buckeye, Aesculus pavia. Yes, spring is on the way, but it does need every moment of winter to get ready for it -- I'll wait right here.
|
Seedling Aesculus pavia
|
During this season of giving I can’t help but think of those that need the best gift we can give them – our support. I’m talking about the things that we co-habit the Earth with: the plants, the insects, the birds, the mammals. We can do things - even small things - to give them a bit of support:
Food – remember the food chain and start with the building blocks: PLANTS. Native plants feed native insects which then feed other native insects and birds. Plants also feed mammals – deer browse on foliage while seeds and nuts feed chipmunks, squirrels and birds. Smaller mammals and birds become food for larger predators. Non-native plants feed very few native insects and therefore do very little to support the populations of all that rely on them. Leaf litter feeds the insects that birds like the brown thrasher hunt.
Water – create a fresh water source in your yard. It can be as small as a single birdbath or a shallow container on the ground. Change it out every few days to keep it fresh and healthy.
|
Brown Thrasher splashing in my birdbath
|
Shelter – providing shelter is so much more than having birdhouses. Birds need year-round protection and evergreen shrubs and trees can provide that. Loose brush piles provide shelter for small mammals as well as daytime cover for birds as they hunt for food. Tall trees provide places for squirrels to nest and dead trees (known as “snags”) provide both food and shelter for certain birds like woodpeckers.
A place to raise their young – birds like robins, mockingbirds and cardinals and many others nest in shrubs that have dense growth in the summer time. Again with the brush piles .... Flat rocks provide the habitat that creatures like salamanders need. Dense leaf litter is the home to many insects and their young.
|
Woodpecker on a snag in my yard
|
Habitat – now think BIGGER than your backyard. Every small piece of space that we can preserve for them in a natural state is a gift that keeps on giving. Here are ideas that get bigger and bigger:
- Convince your friends and neighbors to leave natural places; if each one of us left part of our backyard as natural (still removing any invasives!), imagine the corridor that we could link between us. Birds and mammals need contiguous spaces not isolated pockets. Spread the word.
- Support efforts in your local communities to create city parks and county parks. Volunteer at these parks to teach other people about using native plants and about the importance of removing invasive plants. Your gifts of time and effort are worth more than you know.
- Support your
state parks by visiting them, volunteering through their “Friends of” organization, and supporting legislative efforts to fund them and create new ones. Helping to remove invasives is so helpful - cutbacks in funding have left this job mostly undone, allowing invasive plants to disturb even more natural habitat.
When you're thinking about your new year's resolution, think about how you can help those that live around us.
