This year for the first time and as a result of a multi-year effort Alta Peak CNPS is able to offer a designated list of locally sourced, local native plants for sale to the public.
Why is that important? Two reasons:
- Native plants are best adapted to areas where they already grow, or grew in the past
- Animals are adapted to and rely on local native plants for survival.
This is especially important in California, because the state is incredibly varied. California has both the highest (Mt. Whitney) and the lowest elevation (Death Valley) of any place in the lower 48 states. It’s cooled by the Pacific Ocean, but has extensive deserts inland. It contains grasslands, chaparrals, woodlands, forests, wetlands, deserts. These are the consequences:
- CA has more plant species than any other state (over 7500 species and subspecies).
- Over one-third of CA native plants are found nowhere else.
Just let that sink in for a few moments.
Animal species in an area are adapted to the ecosystem, including the plants, and depend upon it (for example, Monarch butterflies lay their eggs only upon milkweed plants). Even when an animal doesn’t eat a plant directly, its energy ultimately comes from plants. When we move a plant from one place to another, we’re disrupting that adaptation.
Animal diversity echoes plant diversity. According to a recent CNPS Flora article more than 40% of all of North America’s bumblebee species are found in CA. This is an astounding number. Bumblebees are better pollinators of many food crops than are the non-native honeybees, so it is in our direct self interest to foster these native species. Remember point number two (above): Animals are adapted to and rely on local native plants for survival. We all should know that insect species (bees and monarch butterflies for example) are declining. How is the best way to help them? By protecting and restoring local native plant communities.
Here’s an example of what can happen when we don’t use local natives. Many people, hoping to help Monarch butterflies survive and prosper, have planted a milkweed that’s readily available in nurseries: Tropical Milkweed (Asclepias curassavica). But there’s a problem- tropical milkweed doesn’t go dormant in the winter, as do native milkweeds. Because of this, more Monarchs are staying put over the winter instead of migrating south. Monarchs that don’t migrate and continue to reproduce over the winter face several hazards: increased transmission and loads of the parasite OE (Ophryocystis electroscirrha), food shortages, and risk of freezing, leading to lowered survival and reproduction. For this reason the Xerces Society recommends that only locally native milkweeds be planted (Tropical Milkweed- a No-Grow).
One final point. Keystone species are species that have an outsize role in supporting ecosystems- oaks are one example. According to Doug Tallamy: “Oaks are the quintessential wildlife plants: no other plant genus supports more species of Lepidoptera (butterflies and moths), thus providing more types of bird food, than the mighty oak.” Not everyone has the room for an oak, but if you do, seriously consider planting one (this is not to demean other tree species that are extremely important to California biodiversity, such as CA Sycamore and willows).
The take-home message: plant locally native local plants and plant local oaks if you can.