Yucca

Adam's needle (Yucca filamentosa) received a low-flammability ranking in the 2006 Forest Service and NIST study of southern ornamental shrubs. Researchers burned whole plants under controlled conditions using large-scale calorimetry. Their ranking combined ignition, heat release and other measured aspects of burning. It describes that tested species, rather than every plant sold under the yucca name.

Idaho Firewise gives a score of 8 to soapweed yucca (Yucca glauca) and to the 'Ivory Tower' cultivar of Yucca filamentosa. That score carries a suggested minimum separation of 30 feet from the home in the Idaho guide. The cultivar name matters when matching that second recommendation.

The Pacific Northwest guide includes Yucca species in its fire-resistant landscape selection and describes their swordlike leaves. Its recommendations depend on maintaining plant health with appropriate watering and pruning, removing dead material and preserving spacing. A low burn-test ranking and a garden-list inclusion therefore answer different parts of choosing and caring for a yucca.