How to Identify Native Plants
There are certain key features or points to look for that will help in proving a plant's identity. They are outlined below with examples of each.
It may seem that all plant leaves look the same but a closer and detailed look at a leaf can definitely help one distinguish between species. Color, shape, size, texture are major points to look for in a leaf. The leaves of the Black Willow (Salix nigra) are large, tapering to the end, have a distinctive margin and are a very dark but glossy green in color with a lighter green underside. The Eastern Cottonwood (Populus deltoides) has a broader, sort of deltoid or triangular shaped leaf, with a broad base, tapering to a narrow tip. There are rough serrations or teeth along the edges of the leaf. This leaf is dark green in color. Both these plants species have simple leaf structure. The other type is compound leaf as found in poison ivy/oak. Polystichum munitum (Western Sword Fern) has a large divided leaf or frond, which looks like many divided leaves. The appearance of such leaves is feather-like, with rough tips.
One of the easiest methods to identify native plants, is by examining the flowers of the plant. Colors, size, shape, location on the plant itself - very rarely do flowers from different species look alike, so there are few chances of "mistaken identity". Some native plants to look out for are:
- Aristolochia californica or the California pipevine, is a type of vine, that is native to the state of California and has curved, tobacco pipe shaped flowers, with light purple stripes on them.
- The American Willow or Pussy Willow (Salix discolor) has very soft and silky catkins or buds as flowers with grayish or silver fine fur.
- Red and black chokeberries (genus: Aronia) have clusters of small, dainty 5 petal flowers, either pale pink or white in color.
- The New England Aster (Symphyotrichum novae-angliae) has a bright yellow disc at its center and the petals can be dark purple or rose in color. This plant is found in nearly every U.S. state.
In the plant kingdom, dimensions are a key identifying factor. Trees have height and wide, thick branches. Their trunk or girth is also large. Flowers are located mostly on the tip of branches. Shrubs are lower or closer to the ground, with many stems and branches.
Their height is less but shrubs have a larger shadow and coverage with their widespread branches. Their stems are thinner as compared to trees. During their blooming season, flowers seem to envelop the entire shrub, appearing to be growing all over the plant.
To illustrate this point, compare the differences between the Gray Birch (Betula populifolia) and the Blackhaw Viburnum or Stag Bush (Viburnum prunifolium). The Birch reaches heights between 7 to 9 meters while the Blackhaw reaches a maximum of 5 meters in height. The bark of the Blackhaw is reddish-brown while that of the Birch is chalkish white or gray. Even their structure is different, with the Birch having multiple thick trunks and the Blackhaw is the short but stout type, with widespread branches. Smaller plants like wildflowers, ferns and grasses are distinct enough, when judged dimension wise.
Tree bark can be distinct or nondescript and common. Bark can be smooth or peeling, in blotches or in uniform color. Some trees like the Honey locust (Gleditsia triacanthos) have thorns coming out of their bark, so it is easy to identify this tree. The bark of an Oak tree is brown, with fissures and in a fluted pattern. Willow bark is similar. Cedar bark is very fluted. The Black Walnut (Juglans nigra) has a very black and furrowed bark, which makes it noticeable. The sap or secretions of a plant can be milky or creamy white, red or brown, transparent and sticky or thick or thin. Odors from the plant or tree can also help in determining its identity. Branches of a pine tree give off an appealing smell. Some plants like the California pipevine, have foul-smelling flowers that attract small insects. Fruits and seeds are also dead giveaways to a plant's identity, from the Red Mulberry (Morus rubra) with its little red berry-like fruit to the bright red drupes of the Flowering Dogwood (Cornus florida).
In addition to identifying native specimens based on features, field work also includes note taking, detailed listing of features, drawing or collecting live samples of the plant, like a leaf or flower. Carry a hand lens or small magnifying glass, for a zoomed in look at the plant's features. Field guides and plant key books can help for quick looking-up. Off the field, refer to horticulture or botanical books and compare your notes and samples, to establish the plant's identity. The USDA plant database online has a very extensive listing of species, photos and information and serves as a great web-aid designed to suit your plant identifying needs. The above features are all great ways to identify native plants, and in fact useful for identifying any plant type, so what are you waiting for? Get out in the great outdoors and go green!