University of Washington Botanic Gardens

1)   Rhododendron luteum

• Also called Yellow Azalea or Honeysuckle Azalea.
• Despite the sweet perfume, the nectar is toxic. Records of people poisoned by eating the honey date back to 4^th century B.C.
• Cultivated both as an ornamental and as root stock.

2)   Laburnocytisus adamii

• Also known as Adam’s laburnum or broom laburnum.
• Considered a horticultural curiosity, some branches produce yellow flowers while other branches produce coppery-pink flowers.
• Located along Arboretum Drive south just south of the Sassafras.

3)   Paeonia Lutea var. Ludlowii

• A rare Chinese form of tree peony.
• Large saucer-shaped blooms appear in late spring in a beautiful clear yellow color.
• Avoid pruning except to remove large branches.
• Located along Arboretum Drive across from the Sequoias.

4)   Petteria ramemtacea

• Fragrant yellow flowers in early summer and tri-foliate leaves make this unusual plant resemble a shrubby golden chain tree.
• Native to Yugoslavia and Albania.
• This specimen is located along the east side of Arboretum Drive behind the Dove Tree.

5)   Sophora microphylla

• Known as the Kowhai tree in its native New Zealand.
• The blooms of the Kowhai are regarded as New Zealand’s national flower.
• All parts of the Kowhai, but particularly the seeds, are poisonous to humans.
• Located along Arboretum Drive

1)  Azara lanceolata

• An evergreen shrub with arching branches and lance-shaped leaves, A. lanceolata bears clustered yellow flowers in mid to late spring. Native to South America, Azaras is a genus of 10 species within the family, Flacourtiaceae.
• Located in the double lot on the east side of Arboretum Drive.

2)  Cercis siliquastrum   (Judas-tree)

• A deciduous tree usually of low, bushy habit, C. siliquastrum forms magenta-colored flower clusters before and with the leaves, and often on the main branches.
• The popular name of Judas-tree is derived from the legend that this was the tree upon which Judas hanged himself after the great Betrayal.
• Located along Arboretum Drive near the Rock Roses.

3)  Citrus trifoliata

• Native to Northern China and Korea, C. trifoliata is a deciduous shrub armed with sharp spines along rigid green shoots. Solitary, fragrant white flowers are borne in late spring, and often again in autumn.
• Located west of Azalea Way near the Boyer parking lot.

4)  Fothergilla major

• Erect terminal spikes of fragrant white flowers give this upright shrub a charming quality during the spring season.
• Native to the Allegheny Mountains, from Virginia to South Carolina.
• This specimen is located near the ongoing Pacific Connections Gardens Project, east of Arboretum Drive.

5)  Malus ‘Makamik’
As with many of our flowering crabapples, M. ‘Makamik’ is currently showing off its clustered pink to purple blossoms.

• Conveniently located within Crabapple Meadow, east of Arboretum Drive.

1) Camellia japonica ‘Drama Girl’

• Hybridized in 1950, this winner of the RHS Award of Garden Merit has very large, semi-double, deep salmon rose pink flowers.
• Located in the Camellia Collection on the east side of Arboretum Drive.

2) Ilex aquifolium ‘Ferox Argentea’ (Hedgehog Holly)

• This holly is a large, bushy evergreen shrub with small, spiny leaves whose upper surfaces as well as the margins are broadly-edged with creamy white.
• This male clone produces no berries, and is not invasive like other English holly varieties are.
• Located near Boyer Ave. in the Holly Collection.

3) Pieris japonica ‘Crispa’

• This plant has the early spectacular flowers of Pieris, with the added bonus of unusual crinkled leaves, and a somewhat more compact growth.
• Located in Rhododendron Glen, above the Upper Pond.

4) Rhododenron ‘Ibex’

• A striking red, early flowering Rhododendron.
• Hybridized in 1941 by Leopold de Rothschild, an English banker and conservative politician best remembered as the creator of Exbury Gardens.
• Located on the Upper Trail, across from the Magnolia Collection.

5) Rubus spectabilis (Salmonberry)

• A species of Rubus native to the western coast of North America from west central Alaska to California.
• Salmonberries were an important food for indigenous peoples. Traditionally, the berries were eaten with salmon or mixed with oolichan (a Pacific smelt) grease or salmon roe.
• An important part of our native matrix, and can be found throughout the Arboretum.

1)   Berberis darwinii

• Darwin’s barberry is one of the showiest of the genus with striking orange flowers opening from red buds.
• Unlike most other Berberis (including our native species), Berberis darwinii produce sweet fruit in the fall.
• A large mass can be found in the Chilean entry garden in Pacific Connections, as well as the Chilean hillside along Lake Washington Boulevard.

2)   Osmanthus x burkwoodii

• A hybrid of O. decorus and O. delavayi, Osmanthus x burkwoodii produces the very fragrant flowers typical of the genus.
• Several large specimens can be found along Foster Island Road.

3)  Ribes malvaceum var. viridifolium ‘Ortega Beauty’

• Though similar to Ribes sanguineum, the Chaparral currant has a more open form and the leaves are particularly resinous – (touch and smell the leaves).
• Many cultivars of R. sanguineum and R. malvaceum can be found in the Cascadia area of Pacific Connections.

4)  Salix acutifolia ‘Pendulifolia’

• Located in the twig bed of the Witt Winter Garden, this willow produces catkins that rival rabbits for softness.

5)  Stachyurus himalaicus

• This Stachyurus is located along the footpath of the Sino-Himalayan hillside.
• This specimen is a superlative example of both form and flowers for the genus.
• Stachyurus species can also be found in the Woodland and Winter Gardens.

1)  Coriaria napalensis

• This is one of three species of Coriaria in the Arboretum.
• It is growing near Azalea Way, north of the Pine Collection (grid 23-1W).
• Our other two species are C. japonica in Rhododendron Glen and C. sarmentosa (a New Zealand native) on Arboretum Drive in grid 11-7E.

2)  Lindera obtusiloba

• Native to China, Japan, and Korea
• L. obtusiloba is most noted for its early spring flowers, but also has rare fall color (pure yellow) on its openly-spreading form.
• See it in the Woodland Garden or west of the Graham Visitors Center.

3)  Mahonia aquifolium   (Tall Oregon Grape)

• Mahonia is now officially renamed “Berberis”.
• Native to western North America; now in bloom throughout the Arboretum.

4)  Pieris japonica   ‘Valentine’s Day’

• This pink cultivar is at the south end of our Lilac Collection in 29-1W on Azalea Way.
• More Pieris as well as several other genera in the Erica family (Clethra, Kalmia, Vaccinium, and others) can be found on the lower trail north of Rhododendron Glen.

5)  Ruscus aculeatus   (Butcher’s Broom)

• Ruscus is, surprisingly, a member of the Iris family.
• The “leaves” are actually modified stems called cladodes; the tiny flowers and subsequent berries that seem to be in the center of the leaf are actually at the leaf axil.
• These plants are in the north end of the Winter Garden.