'US-897' is a recently released rootstock from the USHRL program that has been extensively evaluated in Florida by USHRL personnel as indicated in the source history. More information on these evaluationsis available from Dr Kim Bowman of USHRL. It has also been included in some trials in California conducted by Prof Mikeal Roose of the University of California, Riverside. According to the Release Notice, "In all field avaluations, US-897 rootstock produced dwarf trees that had good fruit productivity on a canopy volume basis and yielded good fruit quality. The major positive attributes of this new rootstock are resistance or tolerance to citrus tristeza virus, Phytophthora palmivora, and Diaprepes root weevil, dwarfing effect on scion tree size, induction of high fruit quality, induction of good productivity per canopy volume on grafted scions, and ease of seed propagation. A notable negative of this rootstock may be a relatively high rate of tree loss after ten years of age to citrus blight or a similar disease." (RR Krueger, 04/02/2008)