Those look like olive trees? Grasses and agaves -- a drought-tolerant alternative to lawn in hot, dry climates. Oehme Van Sweden drought tolerant demonstration garden with grasses and agave at Cornerstone.
Add an airy, delicate look to your landscape with graceful miscanthus. Its arching foliage and feathery summer plumes make it a great late-season privacy screen (it can reach 8 feet tall or more) or a soft backdrop for your favorite perennials.