The 'heart and sole' of any Restoration project is California Native Plants. These plants provide a food source for numerous indigenous mammals, birds and insects, some exclusively. The Coast Live Oak, i.e., supports over 500 species with habitat, as well as a source of food. With increased development, California Native Plant Communities or truly wild habitats, have declined and their range greatly reduced. This is why indigenous plants are so important in Restoration projects.
It is important to avoid cross fertilization of non-local plants with indigenous California Natives. Seed gathered to create plant material for Restoration projects, should be found no farther than 50 miles away from where they are intended to be planted. This advice is provided by the California Native Plant Society. This is particularly true with wildflower seed which are typically gathered from everywhere, packaged and sold. Seed gathered in this fashion, can be hundreds of miles away from the original location it was harvested when finally planted. Before a Restoration project begins, seed for the project should be gathered and grown at a nursery, to provide mature plant material when the Restoration project is finally finished. Preparation of the nursery stock for Restoration projects should begin years before construction begins. I know of projects considered successful, that were planted with California Native trees, with seed gathered far from the source where the trees were finally planted. Restoration projects done in this manner, are not serving the public good or making the environment better.
Ideally, Caltrans could play a very important part in correcting the difficulty fauna have of finding California Native Plants in California for sustenance. Indigenous plants could be planted all along the public right of way on every highway, providing nourishment for local mammals, birds and insects. However, if done incorrectly, which is more likely, the seed population of indigenous plants could become further deteriorated.
Now, I would like to discuss briefly the importance of a undiluted genetic plant stock. Preservation of the genetic components of maize or Indian corn is essential to the protection of our domestic corn crop. Often, hybridization can diminish the natural disease resistance of any modified species. Keeping the genetic components of ancient corn intact is one way of protecting our corn crop from disease in the future. Also, plant species are a fundamental ingredient in the production of numerous medicines. Theoretically, every plant lost or diminished, can lead to a disease not cured. I believe there are some parallels between California Native Plants and maize in the necessity of keeping the seed stock undiluted.
We hope you consider these issues in your Restoration project. Please, call Alder Landscape Architecture to discuss the important issues of your project. They have the experience to design your Restoration project correctly.