Cultivar 1398: Tom Thumb

Tom Thumb is documented as a plum, specifically a P. besseyi hybrid, in a University of Minnesota Agricultural Experiment Station bulletin on stone fruit pollination studies [S1]. The source does not describe its fruit, origin, breeder, release date, tree habit, or culinary use.

The record places Tom Thumb in a table of native and hybrid plums tested for pollen germination on artificial media [S1]. In that table, it appears among hybrid plum varieties with very low pollen germination [S1]. The bulletin also states that hybrid plum varieties often had low pollen viability, while native plum species generally had higher viability [S1].

Its hardiness is not directly stated. The only geographic context is the University of Minnesota work at Excelsior, Minnesota, in a study of native and hybrid plums used in northern fruit breeding and pollination trials [S1]. This makes Tom Thumb relevant to cold-region plum research, but it does not prove a zone rating or winter survival claim.

The clearest taxonomic point is that Tom Thumb was treated as a P. besseyi hybrid [S1]. The available source gives no direct parents, sibling cultivars, descendants, or later breeding use. The main value of this record is pollination evidence: Tom Thumb was included in the Minnesota plum pollination dataset, but its pollen performance was poor in the table where it appears [S1].

Summary source basis

• S1: Pollination Studies with Stone Fruits

This summary currently draws chiefly from Plant Introductions, with 4 additional supporting sources linked below.

Featured source descriptions

“Tom Thumb cherry is the later name assigned in the 1922 list to True to Seed No. 2 from an earlier series.”
— ^[4]

“True to Seed No. 2 was practically like Sapa in fruit, but the plant was a low bush with much the habit of its granddam, the native sand cherry.”
— ^[4]

“Listed among other cherry-plums described in these Bulletins.”
— ^[2]

“Oka is described as taller than the Tom Thumb Cherry.”
— ^[4]

Direct parent cultivars

• No direct linked parent cultivars promoted yet.

Parentage claim text

• P. salicina x P. besseyi

Derived or downstream cultivar links

• No derived or downstream lineage links yet.

Source-story quotations

• Tom Thumb — P. Besseyi hybridPollination Studies with Stone Fruits, p3
• Tom Thumb — P. Besseyi hybridPollination Studies with Stone Fruits, p3

Taxonomy context: No family-tree context surfaced yet.

Related cultivars mentioned in source context