Publication #ENH-497
Koelreuteria paniculata: Goldenraintree1
Introduction
Goldenraintree grows 30 to 40 feet tall with an equal spread, in a broad, somewhat irregular globe-shape. Some trees appear vase-shaped. Although it has a reputation for being weak wooded, it is rarely attacked by pests and grows in a wide range of soils, including high pH soils. Goldenraintree tolerates dryness and casts little shade because of the open growth habit. It makes a good street or parking lot tree, particularly where overhead or soil space is limited, due to its adaptive abilities. The tree grows moderately and bears large panicles of bright yellow flowers in May (USDA hardiness zone 9) to July (USDA hardiness zone 6) when few other trees bloom. It is not as showy as Koelreuteria bipinnata but is much more cold-tolerant. The seed pods look like brown chinese lanterns and are held on the tree well into the fall. Figure 1. Middle-aged Koelreuteria paniculata: Goldenraintree
General Information
Scientific name: Koelreuteria paniculata
Pronunciation: kole-roo-TEER-ee-uh pan-ick-yoo-LAY-tuh
Common name(s): Goldenraintree, Varnish-Tree
Family: Sapindaceae
USDA hardiness zones: 5B through 9B (Fig. 2)
Origin: not native to North America
Invasive potential: According to the IFAS Assessment of the Status of Non-Native Plants in Florida's Natural Areas (Fox et al. 2005), Koelreuteria paniculata (goldenraintree) may be used with caution in the central and southern zones of Florida, but should be managed to prevent its escape (counties are listed by zone at: http://plants.ifas.ufl.edu/assessment ); and is not considered a problem species and may be used in north Florida.
Uses: shade; sidewalk cutout (tree pit); street without sidewalk; specimen; parking lot island < 100 sq ft; parking lot island 100-200 sq ft; parking lot island > 200 sq ft; tree lawn 3-4 feet wide; tree lawn 4-6 feet wide; tree lawn > 6 ft wide; urban tolerant; highway median; reclamation; container or planter
Availability: not native to North America
Figure 2. Range
Description
Height: 30 to 40 feet
Spread: 30 to 40 feet
Crown uniformity: irregular
Crown shape: round, vase
Crown density: open
Growth rate: moderate
Texture: coarse
Foliage
Leaf arrangement: alternate (Fig. 3)
Leaf type: even-pinnately compound, odd-pinnately compound
Leaf margin: lobed, incised, serrate
Leaf shape: ovate, oblong
Leaf venation: pinnate
Leaf type and persistence: deciduous
Leaf blade length: less than 2 inches, 2 to 4 inches
Leaf color: green
Fall color: yellow
Fall characteristic: showy
Flower
Flower color: yellow
Flower characteristics: very showy
Fruit
Fruit shape: oval, elongated
Fruit length: 1 to 3 inches
Fruit covering: dry or hard
Fruit color: green, brown
Fruit characteristics: does not attract wildlife; showy; fruit/leaves not a litter problem
Trunk and Branches
Trunk/bark/branches: branches droop; not showy; typically one trunk; thorns
Pruning requirement: needed for strong structure
Breakage: resistant
Current year twig color: brown
Current year twig thickness: thick
Wood specific gravity: unknown
Culture
Light requirement: full sun
Soil tolerances: clay; sand; loam; alkaline; acidic; extended flooding; well-drained
Drought tolerance: high
Aerosol salt tolerance: moderate
Other
Roots: not a problem
Winter interest: no
Outstanding tree: yes
Ozone sensitivity: sensitive
Verticillium wilt susceptibility: susceptible
Pest resistance: resistant to pests/diseases
Figure 3. Foliage
Use and Management
The root system is coarse with only a few but large roots, so transplant when young or from containers. Do not transplant in the fall as success rate is reportedly limited. Considered a city tolerant tree due to tolerance to air pollution and ability to withstand drought, heat and alkaline soils. It also tolerates some salt spray but requires well-drained soil. It would be hard to find a more adaptive yellow flowering tree for urban planting. It makes a nice patio tree, creating light shade but its brittle wood can break easily in windy weather. The tree has only a few branches when it is young and some pruning to increase branchiness helps sell the tree. Prune the tree early to space major branches along the trunk to create a strong branch structure and the tree will be longer-lived and require little maintenance. Dead wood is often present in the canopy and should be removed periodically to maintain a neat appearance. Only single-stemmed trees trained in the nursery with well-spaced branches should be planted along streets and parking lots. One cultivar is listed; `Fastigiata' - upright growth habit. Pests
Occasional attacks by scale may be seen. Sprays of horticultural oil control overwinter stages. Boxelder bug can be a menace. Diseases
Koelreuteria is subject to few diseases. A canker causes dead and sunken areas on the bark. Coral pink fruiting bodies develop on the diseased bark. Prune out infected branches and fertilize to maintain tree health. Verticillium wilt attacks Koelreuteria . The disease causes wilting and death of leaves on infected branches. Eventually the entire tree may be killed. Fertilize to stimulate growth. There are no chemical controls. Footnotes
1. This document is ENH-497, one of a series of the Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date November 1993. Revised April 2007. Visit the EDIS Web Site at http://edis.ifas.ufl.edu.
2. Edward F. Gilman, professor, Environmental Horticulture Department; Dennis G. Watson, associate professor, Agricultural Engineering Department, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville FL 32611.The Institute of Food and Agricultural Sciences (IFAS) is an Equal
Opportunity Institution authorized to provide research, educational
information and other services only to individuals and institutions
that function with non-discrimination with respect to race, creed,
color, religion, age, disability, sex, sexual orientation, marital
status, national origin, political opinions or affiliations.
For more information on obtaining other extension publications,
contact your county Cooperative Extension service.
U.S. Department of Agriculture, Cooperative Extension Service,
University of Florida, IFAS, Florida A. & M. University Cooperative
Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.
