Brassicaceae greens, Savoy, kohlrabi, and gai lan ("Brassica oleracea"), turnip, napa cabbage, bomdong, bok choy and rapini ("Brassica rapa"), rocket salad/arugula ("Eruca sativa"), garden cress ("Lepidium sativum"), watercress ("Nasturtium officinale") and radish ("Raphanus") and a few spices like horseradish ("Armoracia rusticana"), "Brassica", wasabi ("Eutrema japonicum"), white, Indian and black mustard ("Sinapis alba", "Brassica juncea" and "B. nigra" respectively). Vegetable oil is produced from the seeds of several species such as "Brassica napus" (rapeseed oil), perhaps providing the largest volume of vegetable oils of any species. Woad ("Isatis tinctoria") was used in the past to produce a blue textile dye (indigo), but
Vegetable oils as alternative energy amount of energy as vegetable oil is low compared to many of the potential replacements for fossil fuels. The list of vegetable oils article discusses which types of vegetable oil are used for fuel and where different types are grown. Vegetable oil is used for transportation in four different ways: The transition can start with biodiesel, vegetable oil refining, and vegetable oil blends, since these technologies do not require the capital outlay of converting an engine to run on vegetable oils. Because it costs to convert vegetable oil into biodiesel it is expected that vegetable oil will always be cheaper