Denomination: 'Yosnowmass'
Trade name: Snowmass
Botanical Name: Chrysanthemum ×morifolium
Applicant/Holder: Syngenta Crop Protection AG
Schwarzwaldallee 215
Breeder: Wendy Bergman, Syngenta Flowers, Inc., Alva, United States of America
Agent in Canada: Keepsake Plants, Ltd.
P.O. Box 370
268 Seacliff Drive West
Leamington, Ontario
N8H 3W3
Tel: 519-326-6121; Ext.224
Application Date: 2005-10-03
Application Number: 05-5069
Date Withdrawn: 2008-11-24

Variety Description

Variety used for comparison: 'Yoyukon' (Yukon)

Summary: From the beginning of short-day application, the plants of 'Yosnowmass' take 8 weeks to flower whereas those of 'Yoyukon' take 7 weeks. The margins of the sinuses between the lateral lobes of the leaf are diverging and parallel for 'Yosnowmass' while they are parallel to touching for 'Yoyukon'. 'Yosnowmass' has a smaller flower head diameter, shorter ray floret and shorter ray floret corolla tube than 'Yoyukon'.


PLANT: year round cultivation for pot production, disbud flowering type, 8 week response group
STEM: green, no anthocyanin colouration

LEAF: dark green, 1.7:1 length/width ratio, truncate base, diverging and parallel margins of sinus between lateral lobes

FLOWER HEAD: double decorative incurve type, self-coloured, white colour group, very dense ray florets
RAY FLORET: incurved type, longitudinal axis of majority is incurving, strong curvature, incurved end, dentate tip, white on upper and lower sides, solid colour pattern on upper side

Origin & Breeding History: 'Yosnowmass' is a product of a planned breeding program conducted by the breeder, Mrs. Wendy R. Bergman, an employee of Yoder Brothers, Inc. in Barberton, Ohio, USA. It originated from a cross between proprietary Chrysanthemum seedling selection designated 'YB-4699' as the female parent and another proprietary Chrysanthemum seedling selection designated 'YB-4976' as the male parent. This cross was conducted by the breeder in November 1999, in Salinas, California, USA. 'Yosnowmass' was discovered and selected in November 2000, as a single flowering plant among the progeny of the stated cross growing in a controlled environment in Fort Myers, Florida, USA. The selection of this plant was based on its uniform plant growth habit, desirable inflorescence form and floret colours, fast response time and excellent post-production longevity. Asexual reproduction of 'Yosnowmass' by vegetative tip cuttings was first conducted in Fort Myers, Florida, USA in March 2001.

Tests & Trials: Trials for 'Yosnowmass' were conducted in the fall of 2007 at Yoder Canada Ltd. in Leamington, Ontario. They were performed under greenhouse conditions similar to those used in commercial Chrysanthemum production. 30 unrooted cuttings per variety were directly stuck into 15 cm pots with 5 cuttings per pot and 6 pots per variety. The pots were spaced 30 cm apart. The plants were pinched once prior to short day treatment. All plants had the central bud removed. Observations and measurements were taken from 10 plants of each variety on October 29, 2007. All colour determinations were made using the 2001 Royal Horticulture Society (RHS) Colour Chart.

Comparison tables for 'Yosnowmass' with reference variety 'Yoyukon'

Flower head diameter (cm)

  'Yosnowmass' 'Yoyukon'
mean 12.0 17.3
std. deviation 0.48 0.94

Ray floret length (cm)

  'Yosnowmass' 'Yoyukon'
mean 5.2 6.1
std. deviation 0.39 0.54

Length of ray floret corolla tube (cm)

  'Yosnowmass' 'Yoyukon'
mean 2.0 3.1
std. deviation 0.59 0.57

Click on image for larger view
Chrysanthemum: 'Yosnowmass' (left) with reference variety 'Yoyukon' (right)

Click on image for larger view
Chrysanthemum: 'Yosnowmass' (left) with reference variety 'Yoyukon' (right)

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