Invasive species means an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.
Beam axis means a line from the source through the centers of the x-ray fields.
Beam scattering foil means a thin piece of material (usually metallic) placed in the beam to scatter a beam of electrons in order to provide a more uniform electron distribution in the useful beam.
Invasive plant species means species of plants not historically found in California that spread outside cultivated areas and can damage environmental or economic resources. Invasive species may be regulated by county agricultural agencies as noxious species. Lists of invasive plants are maintained at the California Invasive Plant Inventory and USDA invasive and noxious weeds database.
Aquatic invasive species means any invasive, prohibited,