Frost Marsh Grapefruit

Frost Marsh is a nucellar seedling selection of Marsh and was introduced commercially in 1952. UCR classifies it as a white grapefruit. The collection entry records H. B. Frost received Marsh seed in 1915; a reproduced 1967 account says it was planted in 1916. The source does not establish the selection year. UCR separately describes Thompson (Pink Marsh) as a Marsh limb sport.^⁠[1]

The CRC3184 accession note describes almost-round fruit with smooth light-yellow rind and pale-yellow, tender, juicy flesh; it reports late maturity and good holding on the tree. The reproduced general Marsh account describes few or no seeds and buff-colored flesh; these general Marsh traits are not a CRC3184-specific seed count and remain distinct from the accession-specific pale-yellow observation.^⁠[1]

UCR describes the CRC3184 tree as vigorous, large, and spreading and lists January–May ripening at Riverside. The reproduced general Marsh account says the high heat requirement restricts commercial production to very hot climates.^⁠[1]