Yuca or yucca, depending upon whether you use the older or newer spelling of the word, is one of my favorite veggies and I sometimes add unsalted yucca leftovers to my birds' soft food mix. I actually prefer the taste of the yucca root to that of potatoes. It has been used for many years as a folk remedy for arthritis, rheumatism, gout, and cystitis. It is a staple food in South America and some of the islands of the West Indies. If you have an older bird, this might be a good addition to the diet once or twice a week, since parrots too can develop painful, arthritic joints.
Parrots enjoy starchy foods in their diet.