<i>Thuja </i>plant named ‘RutThu4’

Abstract

A new and distinct cultivar of Thuja plant named ‘RutThu4’, characterized by its compact, globose growth, similar in shape but larger in size and with a faster growth rate than some other Thuja occidentalis cultivars. ‘RutThu4’ also has disease resistance when grown in USDA Zone 8a, and has demonstrated both heat tolerance as well as cold hardiness to about −34° F. in trials conducted in Minnesota.

Claims

1. A new and distinct cultivar of the Thuja plant named ‘RutThu4’ as illustrated and described herein.

Description

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

(1) The accompanying, colored photographic illustrations show the overall appearance and distinct characteristics of the new cultivar Thuja ‘RutThu4’ showing the colors as true as possible. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description. The photographs were taken around June, 2021 of plants grown outdoors in Watkinsville, Ga.

(2) The photograph labeled FIG. 1 depicts a side view of a typical 7-year-old ‘RutThu4’ plant showing the rounded, compact globose form and features.

(3) The photograph labeled FIG. 2 depicts a close-up view of the branches and needles of a typical 7-year-old ‘RutThu4’ plant.

DETAILED BOTANICAL DESCRIPTION

(4) The following traits have been consistently observed in the original plants of the new varieties and in asexually propagated progeny grown in Watkinsville, Ga., (and some in Minnesota) and, to the best knowledge of the inventors, their combination forms the unique characteristics of the new variety ‘RutThu4’.

(5) Throughout this specification, color names beginning with a small letter signify that the name of that color, as used in common speech, is aptly descriptive. Color names beginning with a capital letter designate values based upon The R.H.S. Colour Chart, 5th edition published by The Royal Horticultural Society, London, England in 2007, except where general terms of ordinary dictionary significance are used

(6) The aforementioned photographs and following observations, measurements, and values describe plants of the Thuja cultivar named ‘RutThu4’. Data were collected from a horticulture farm in Watkinsville, Ga. from 6-year-old plants. The average low temperatures ranged from about 20° F. to 30° F. in the winter and about 90° F. to 100° F. in summer. Botanical classification: Thuja occidentalis ‘RutThu4’. Commercial classification: Ornamental conifer. Parentage: Open pollination of Thuja occidentalis ‘Filiformis’ by unknown pollen parents. Growth and propagation: Propagation type.—Terminal or sub-terminal hardwood cuttings. Growth rate.—Slow to moderate. Root description.—Typically about 2-5 roots arising from the base of the cuttings. Rooting habit.—Good. Plant description: Habit.—Of 6-year-old plant in field — compact round/globose, about symmetrical. Usage.—Various uses, including landscaping, ornamental, container, border, hedge, and mass planting. Vigor.—Moderate. Size of 6-year-old plant.—A. Height: from soil level to top of plant, about 58 inches. B. Width: about 80 inches. C. Ratio: about 0.73. Branch/stem (terminal tuft).—A. Quantity: numerous. B. Length: about 13-14.5 cm. C. Base Diameter: about 2-3 mm at about 15 cm from tip. D. Branch angle: about 65° from center. E: Odor (of bruised stem): moderate evergreen scent. F. Internode length: about 1-1.5 mm (about 5 internodes per sample). G: Color (R.H.S.): Greyed-orange 166A. H: Strength of lateral branches: moderate. I: Pubescence: has scale that peel off but do not shed. J: Shape: round. Leaf.—A. Leaf type: needles. B. Mature size (L×W): about 5-9 cm×about 2-3 cm. C. Arrangement on stem: alternate. D. Aspect: upright. E. Color (R.H.S.): summer — upper and lower, Green 137B, tips have tinge of Yellow-Green 144C. winter — upper is Greyed-orange 165A; lower is Greyed-Orange 166D. F. Leaf Number: average of about 8 per cm/stem. G. Apex: acute. H. Base: cuneate. I. Margin: entire. J. Shape: linear with scale-like structure, no lobes present. K. Pubescence: none. L. Venation: none. M. Texture: smooth, glossy. O. Odor when crushed: light evergreen scent. Coning production.—None observed. Seed.—None observed. Weather/temperature tolerance: Plants of the new Thuja have been observed to grow in USDA Zone 8a, with heat tolerance, and have a USDA Zone range 3-8. ‘RutThu4’ has also been cold hardy to about −34° F. in trials conducted in Minnesota. Disease/pest resistance: To date, plants of the new Thuja have been observed to have disease resistance Passelora spp. in USDA Zone 8a when grown under standard conditions.