Cultivar 1403: Hazel

Hazel is a plum cultivar listed as Prunus americana in University of Minnesota sources. A 1951 Minnesota Agricultural Experiment Station bulletin rated it as a good pollinizer. It had a medium bloom season and successfully pollinated 14 tested varieties [S2]. Later University of Minnesota thesis work treated Hazel as a winter hardy plum in trials on seed germination, seedling establishment, herbivore pressure, suckering, and invasive potential [S1].

The packet does not give Hazel's breeder, release date, parentage, or introduction history. Its clearest identity is as an American plum cultivar used in Minnesota cold climate Prunus research and pollination studies [S1] [S2]. In the 2016 thesis table of trial material, Hazel appears as a plum, P. americana L. 'Hazel', with collection location listed as HRC. The table lists 12 greenhouse replications and 14 field replications [S1].

No source in this packet describes Hazel's fruit size, color, flesh, flavor, ripening season, or culinary use. The evidence instead describes its reproductive and seedling behavior. In greenhouse germination data, Hazel had 54.2% germination without scarification and 50% with scarification. Average germination times were 1.6 and 2.0 weeks [S1]. Another field environment table reports 50.0% germination after 25 months of storage and 70.8% after 1 month [S1].

Hazel's progeny performed strongly in the University of Minnesota seedling establishment work. The thesis summary says progeny from Hazel and several other plum cultivars had high germination, vigorous seedling growth, low to moderate herbivore pressure, and limited suckering. The thesis interpreted this combination as indicating invasive potential [S1]. In Experiment III field measurements, Hazel seedlings are listed with initial height of 22.5 cm, initial stem diameter of 2.11 mm, change in diameter of 3.67 mm, and change in trunk cross-sectional area of 24.58 mm² [S1]. Hazel also had the lowest reported average herbivore damage rating among the plum seedlings, 2.7. It differed significantly from seedlings of three other plum cultivars for that rating [S1].

Suckering was present but limited in the recorded trials. Hazel had no greenhouse replications with suckers. In the field, 2 of 14 replications produced suckers, with two total suckers recorded [S1]. The thesis conclusions identified Hazel, Whittaker, Hennepin, and South Dakota as plum cultivars needing more study of invasive risk, especially propagule pressure and seed dispersal mechanisms [S1].

The strongest hardiness context is indirect. Hazel appears in a University of Minnesota thesis focused on winter hardy Prunus species and in a Minnesota stone fruit pollination bulletin. The packet gives no direct USDA zone rating or winter injury statement for Hazel [S1] [S2]. The sources support treating it as a cold climate American plum cultivar in Minnesota research, not as having a specific documented zone in this evidence set.

Hazel's broader taxonomic context is clear but narrow. Both source sets place it with Prunus americana, the American plum [S1] [S2]. The packet contains no direct parentage, siblings, or descendant breeding records for Hazel. Its best supported related context is functional. It appears alongside other winter hardy plum cultivars in germination, seedling establishment, suckering, herbivory, and pollinizer comparisons [S1] [S2].

Summary source basis

• S1: Minnesota #1695
• S2: Pollination Studies with Stone Fruits

This summary currently draws chiefly from Minnesota #1695, with 1 additional supporting sources linked below.

Featured source descriptions

“Has many flowers with aborted pistils in some years; fruits sometimes crack if rains occur during the ripening season.”
— ^[3]

“Fruit form: oval, roundish; apex round; cavity small and shallow.”
— ^[3]

“Tree described as hardy.”
— ^[3]

“Flavor good.”
— ^[3]

Direct parent cultivars

• No direct linked parent cultivars promoted yet.

Parentage claim text

• No direct breeding_cross claim text yet.

Derived or downstream cultivar links

• No derived or downstream lineage links yet.

Source-story quotations

• Average herbivore damage ratings for plums ranged from 2.7 for seedlings from 'Hazel' to 4.8 for seedlings from 'Todd' (Table 8). ... There was significant variation among plums for average herbivore damage rating with seedlings from 'Hazel' differing significantly from seedlings of three cultivars (Table 8).Minnesota #1695, p49
• Average herbivore damage ratings for plums ranged from 2.7 for seedlings from 'Hazel' to 4.8 for seedlings from 'Todd' (Table 8). ... There was significant variation among plums for average herbivore damage rating with seedlings from 'Hazel' differing significantly from seedlings of three cultivars (Table 8).Minnesota #1695, p49
• Progeny from the plum cultivars 'Hazel', 'Whittaker', 'South Dakota', and 'Hennepin' had high % germination, vigorous seedling growth, low to moderate herbivore pressure, and limited vegetative propagation via suckering, indicating invasive potential.Minnesota #1695, p24
• Prunus americana Marsh. 'Hazel' ... demonstrated high germination percentages (>50%) in the field environments of Experiments Iand II and high seedling establishment in Experiment III, indicating a higher invasive risk.Minnesota #1695, p124

Taxonomy context: Genus: Prunus | open genus tree

Related cultivars mentioned in source context