All That's Wild Is Not Native
by Carol Ralph
The Wildflower Show includes all kinds of flowers found growing wild in our area. That includes many non-native species as well as native species.
- Native species are those that were growing here before Europeans arrived. These are the species that our native wildlife evolved with and require. These are the species that our native peoples evolved with and managed.
- Europeans brought many new species with them, intentionally or not. These are the non-native species.
- Some have thrived to the extent of harming our native ecosystems and are classified as "invasive" or "environmental weeds."
Plants do not wear a label saying whether they are native or not. Botanists have to figure that out. To do that, first the species must be identified correctly. Yes, if you want to know if a plant is native or not, you have to identify it. In our real, non-virtual wildflower show we help by including on each species' identification card a colored dot indicating its status as native, non-native, or invasive.
Roadsides, though wild, are often largely or entirely populated by non-native plant species. Here are some common, non-native species seen along the end of Lanphere Rd. in late April, 2020. You will see that some are beautiful and even enjoyed by bumblebees or other insects. That does not make them good candidates for rebuilding our local ecosystem. Only native plants can do that.
Wild Radish (Raphanus sativa)
Jointed Charlock (Raphanus raphanistrum)
Poison Hemlock (Conium maculatum)
These plants are all non-native. They all live for only one or two years but produce an abundance of seed in that short life. With this blitz of seeds from a single colonizing individual over the years they will steadily take over an entire roadside for miles. Wild Radish has pink to purple flowers fading white. Jointed Charlock has pale yellow to white flowers. This photo shows a likely example of what The Jepson Manual calls a "highly variable swarm" created by hybridization between these two species.
Poison Hemlock is toxic if eaten, but harmless to touch. It's soft foliage and general shape before its branches spread out in bloom reminds me of the coniferous hemlock, also soft-foliaged and Christmas-tree shape. The purple spots on its stem and distinctive, musty odor of crushed foliage distinguish it from all similar plants.
Common Dandelion (Taraxacum officinale) (on right) is non-native. With smooth, dark green leaves, this is the species whose foliage is pleasantly edible. The single-flowered stems and turned back bracts right below the flower also distinguish it from the abundant Hairy Cat's Ear, (photo below) also called False Dandelion (Hypocharis radicata). The dandelion starts blooming very early. Hairy Cat's Ear is later, sometimes not in flower for our Wildflower Show. Both are non-native.
Four non-native plants:
Sheep Sorrel
Rattlesnake Grass
Ripgut Brome
Sweet Vernal Grass
All can dominate our habitats.
Sheep Sorrel (Rumex acetosella) is widespread world-wide and familiar to any gardener as a difficult weed to eliminate due to its fine, yellow, long-running underground "roots." It also seeds prolifically from the reddish flowers shown in this picture.
Rattlesnake Grass (Briza maxima) is the easiest grass to identify. The roundish, layered seed heads look very much like rattlesnake rattles as they dangle below the stem. Dried seed heads blowing in the wind also make a rattling sound.
Ripgut Brome (Bromus diandrus) is the fiercest grass around here, especially for dog owners. The long, grabby awns on the seeds have slanted bristles that assure the seed can not back out, can only burrow in deeper when it pokes into the soil or the dog's fur, ear, or nostril.
Rattlesnake Grass and Ripgut Brome are annual plants, sprouting, blooming, seeding, and dying in one year. If you want to eliminate them, you just have to be diligent about preventing any new seeds from forming.
The third grass is a perennial. Sweet Vernal Grass (Anthoxanthum odoratum) continues growing for many years. It grows over winter as well as summer and flowers every year. To eliminate it, you have to pull the whole plant. The sweet smell of a mowed pasture comes from this species. I once heard a botanist say it was the species that would triumph in our coastal prairies. Seeing its steady march and dominance around my house, I believe it. Even though its seeds are benign as far as socks and pets go, this grass is not a good neighbor for habitats.
Two Vetches Vetches are related to peas and share the compound leaves, tendrils to climb with, and flowers with banner, wings, and keel. Vetches are distinguished by the hairs on the pistil being all around the tip, not just on one side, and by the emerging leaflets being folded, not furled spirally. These two vetches are both from Europe.
Spring Vetch (Vicia sativa) has larger leaflets and two or three rosy-purple flowers sessile in the leaf axil,.
A native vetch, American Vetch (Vicia americana) (not pictured here) has similarly colored flowers, but they are arranged 6 - 9 on a long stalk. To find out if it's native or not, you have to know exactly what it is!
Two Chickweeds
The smooth, tender, bright green Common Chickweed (Stellaria media) is another abundant and widespread garden weed. Both chickweeds are non-native.
The leaf behind these two chickweeds is the native Wild Cucumber (Marah oreganus).
English Daisy (Bellis perennis) is familiar as the daisy in lawns, where it can bloom very short if the tall blooms are mowed off.
Three Clovers
In northwestern California we have a good selection of native clovers, as well these three and other non-natives.
White Clover (Trifolium repens) is the common clover in lawns, but also travels to other disturbed sites. It is non-native. The fresh flowers form a round head. As the flowers age, each one droops down, destroying the tidiness of the original show. The leaves often are marked with light "V's."
Subterraneum Clover (Trifolium subterraneum) is a common, creeping clover. The leaves can be fuzzy and have faint, light blotch. The white flowers are inconspicuous, because each head has only a few and because after blooming this head curves over and buries itself in the ground. Unlike other clovers, which are sought after by grazing animals, this species is somewhat toxic to stock in large quantities.
Little Hop Clover, or Shamrock (Trifolium dubium) is one of the non-native species you might find in a gravel parking lot. A few native clovers could be there too.
Creeping Buttercup (Ranunculus repens) presents a cheerful show in wet pastures, roadsides, and gardens. Gardeners often find this species too aggressive to fit in with their plans, as it spreads by creeping as well as by seed. It is a non-native perennial.
English Plantain (Plantago lanceolata) is one of two very common, non-native plantains here. They both grow in disturbed habitats, but can sneak into mostly native landscapes. Several native plantains occur here also, so pay attention to the leaf shape and general form of the plant.
Most of the geraniums in our area are non-native, some very aggressive weeds. (See the invasive plant display in this Wildflower Show.) Dove's Foot Geranium (Geranium molle) is one of them. They all have pink flowers and make lots of seeds.
