Thompson Grapefruit

Originated as a limb sport in a Marsh tree in an orchard owned by W. B. Thompson at Oneco, Florida. While discovered by S. A. Collins in 1913, it did not become available until 1924 when it was named and introduced by the Royal Palms Nurseries, also of Oneco.^⁠[1]

Fruit medium in size, oblate to spherical; areole indistinct or lacking; seeds few or none. Pale to light yellow at maturity. Rind medium-thin, tough, and surface very smooth. Primary flesh color chamois to dark buff, but under favorable conditions light pink (but not in juice); albedo not pigmented; flesh texture tender and juicy; flavor good, similar to Marsh. Holds on tree unusually well, but with considerable fading of color; ships and stores well. Midseason in maturity, (earlier than Marsh).^⁠[1]

Tree vigorous, large, and productive.^⁠[1]

Louzada and Ramadugu describe Thompson as a Marsh grapefruit bud sport and discuss later pigmented cultivars derived from it. A 2011 comparison table rates Thompson (Pink Marsh) flesh pigmentation at one star on its weak-to-very-strong scale and leaves skin pigmentation unmarked; this is a secondary qualitative rating, not a measured pigment value.^⁠[4]⁠[3]