AGEH 28, Fall 2013 Shasta College Arboretum
Fraxinus latifolia, Oregon ash olive family, Oleaceae
Deciduous tree to x ft; native to Sierra Nevada, and N. Calif to BC ID: Lvs 6-12 ”, 5-7 leaflets, end leaflet larger than side ones; tree dioecious (sexes on separate plants); fruit a flat samara with a terminal wing, hanging in clusters Care: Sun, no irrigation when established; tolerates standing water in winter Value: fall color!! Problems: leaf spot fungi even on healthy plants, heart rot on older trees, various insects
Nyssa sylvatica, sourgum, tupelo; Nyssa family, Nyssaceae
Nyssa sylvatica, Sourgum, tupelo
Nyssa sylvatica, Sourgum, tupelo, Nyssa family (Nyssaceae) Native to eastern US; x ft Likes moist deep soil, will tolerate some drought, takes poorly drained, heavy soils Excellent shade tree; fruit sour, but attractive to birds; good fall color even in mild winter climates Fruit a drupe (like olive)
Albizia julibrissin, silk tree, “mimosa” Pea family, Fabaceae
Albizia (Albizzia) julibrissin, silk tree, “mimosa” Native to Asia ID: Tree to 40 ft, twice as wide as high Leaves 2x pinnate, Flowers powder-puff, ‘Rosea’ has richer pink Value: Likes high summer heat; tolerates low water; makes shade; flowers fragrant, attract bees and hummingbirds Problems: somewhat invasive in moist places; a bit messy,
Euonymus alatus, winged burning bush
FALL COLOR!!
Euonymus alatus, winged burning bush Native to northern Asia; needs moderate water ID: leaves opposite, oval, 2 in., twigs usually with corky wings Tolerates full shade, but best color in sun or part shade Species plants can be large (20 ft); buy compact forms ‘Compacta’, etc.; good against dark evergreens (brick walls???)
Invasive in wildlands where there is summer rain (by seeds)
Hibiscus syriacus, rose of sharon
Deciduous shrub from E. Asia x 6-12 ft.; can be trained as small tree, espalier Likes heat, needs sun and moderate water to bloom well
Hibiscus syriacus, rose of sharon Can seed around; buy good forms (sterile triploids: Aphrodite, Diana, Helene, Minerva); For larger flowers, cut back last season’s growth to 2 buds
Populus nigra ‘Italica’, Lombardy poplar
Native to Europe; grows x ft. ID: tall and narrow; leaf slightly diamond-shaped at base, narrowed to long tip, serrate Value: Fast and tough; good for hot summer/cold winter climates; yellow fall color; dramatic in the landscape; wooden shoes Problems: suckers profusely, heaves, clogs sewer pipes
Populus nigra ‘Italica’, Lombardy poplar Forms: ‘Italica’ is a male form, no seeds; female poplars produce lots of cottony fruit
Syringa vulgaris, common lilac ID: shrub, to 20 x 20 ft; leaf heart-shaped (cordate); fragrant flowers
Syringa vulgaris, common lilac Native to E. Europe Needs: sun/ part shade; some water; winter chill, neutral to alkaline soil (add lime if needed) Care: Must prune just after flowering (you have a week, maybe); also, prune out a few of the oldest stems each year to encourage new growth Forms: Zillions (hundreds) of varieties
Salix babylonica, weeping willow
Tolerates poor drainage Large tree (50 ft high and wide), rather short-lived, with weak wood; not suitable for city lots Largely replaced in gardens by S. x sepulcralis ‘Chrysocoma’; there are also other better forms for this same look.
Taxodium distichum Taxodium distichum, swamp cypress
Native to southeastern US 100 ft in the wild, but garden trees x ft. Very tough, tolerant, deciduous conifers of great size, with shaggy bark and graceful sprays of needlelike leaves. Takes waterlogged or dry soils; good for streambank or lake edge.
Metasequoia glyptostroboides, dawn redwood
Native to China; thought to be extinct for millions of years but found again in 1940s. Deciduous conifer. Fast growth when young, to a pyramid-shaped adult of 90 x 20 ft. Likes moisture, so grows in lawns, but surface roots lift turf eventually. Winter form sometimes gawky. Resists oak root fungus.
Dawn redwood vs. swamp cypress
Cornus stolonifera, redtwig dogwood & yellowtwig dogwood C. s. ‘Arctic Fire’ C. s. ‘Flaviramea’
Cornus stolonifera, redtwig dogwood & yellowtwig dogwood Native to n. Cal and north to Alaska ID: multistem shrub 7-9 x 12 ft. Spreads via underground stems and rooting branches Leaves 1.5 – 2.5 in, oval, deep green; flrs small, white, in clusters; fruits white or bluish Value: 4 Fs, esp. red or orange fall color, and red or yellow winter twigs
Cornus stolonifera, redtwig dogwood & yellowtwig dogwood Care: sun to part shade, regular water (streamside plant in the wild); cut back SEVERELY in late dormant season Use: thrives in coldest mountains, even in valleys of S. Cal, useful for streambanks, property boundaries, screen Names: aka red osier dogwood; Cornus sericea very similar
Forsythia x intermedia, forsythia
Origin: China, olive family ID: 4-petal yellow flowers, vase-shaped or arching shrub; leaves oval with pointed tip, serrate; bark with lenticels
Forsythia x intermedia, forsythia Value: yellow flowers in early spring; tough; very cold hardy; can be forced by picking stems in bud Care: sun, moderate water; prune 1/3 of oldest branches to ground each year Forms: get good ones!
Sophora japonica, “popbead tree” J. pagoda tree, Ch. scholar tree
Native to China, Korea, Japan 60 ft high, 2/3 as wide Use for park, shade Leaves compound, alternate Flowers pea-flower-shaped, white, bloom in summer (August) One of the 50 fundamental herbs used in traditional Chinese medicine (aka Styphnolobium japonicum)
Symphoricarpos x chenaultii, coralberry
Native to North America; this form is a hybrid of S. orbiculatus from eastern US. To about 6 ft; best used as a wild thicket for erosion control on steep banks, spreads by root suckers; needs part to full shade in hot climates. Cut stems nice for winter arrangements. There is a one-foot dwarf ‘Hancock’ valued as woodland groundcover.
Alnus cordata, Italian alder
Native to Italy and Corsica ID: 40 x 25 ft.; growth vertical when young; leaf heart-shaped, 4 in., glossy rich green; flrs = male soft catkins and female woody catkins (“cones”) Value: good near creeks, fast growth, flrs good display before lvs; favored in the SW “More restrained than A. rhombifolia.” White alder is our native tall alder
Liriodendron tulipifera, tulip tree magnolia family--Magnoliaceae
Liriodendron tulipifera, tulip tree Native to eastern United States Tallest deciduous tree in the world—200+ ft. in the wild Yellow fall color, even in S. Calif.
Flowers not showy, as carried high on tree; but beautiful up close. Starts blooming when years old Likes deep rich soil, roots shallow so cannot garden under them Susceptible to Ganoderma root/butt rot fungus. Liriodendron tulipifera, tulip tree
Because of its tall, straight trunk and wood that is soft, lightweight, straight-grained, resistant to splitting, and easily worked, Native Americans and early pioneers frequently hollowed out a single log to make a long dugout canoe. Its wood is sold commercially as “yellow poplar,” & used for furniture, musical instruments, interior finishes, shingles, & boats. Liriodendron tulipifera, tulip tree
ID—tall straight growth, 4-lobed leaves like no other. ‘tulipfera’ means ‘tulip bearing’
Magnolia family (Magnoliaceae) Ancient flowering plant group; some of the earliest fossil flowers found look like magnolias
Magnolia x soulangeana ‘Rustica Rubra’; RR saucer magnolia More pix
Magnolia x soulangeana ‘Rustica Rubra’ Saucer Magnolia x ft; Value: spectacular bloom in deep pink before leaves; this form with spectacular fruits (pendent, rose pink, with red “seeds”) attractive to birds Hybrid of M. denudata and M. liliiflora
Magnolia x soulangeana ‘Rustica Rubra’ Saucer Magnolia Fruit a follicle, shaped like misshapen sausage from side; this is a view from below
What’s a follicle? A follicle is a dry fruit, developing from a single pistil, opening along one side; magnolia fruit is an aggregate of follicles (this magnolia fruit is typical of bull bay magnolia, not typical of saucer magnolia)
Wistaria sinensis, Chinese wisteria
VIGOROUS vine, beautiful but messy Invasive into moist areas Most common wisteria in West Leaves with 9-13 leaflets Notice the direction of twining for ID:Counterclockwise= W. sinensis; Clockwise= W. floribunda Plant toxic (esp seeds) Prune in winter
Celtis australis hackberry
Lagerstroemia indica Crape Myrtle
Colorful and long lasting flowers Blooms in the summer and autumn Panicles of crinkled flowers with crepe-like texture
Lagerstroemia indica Crape Myrtle Bark shed throughout the year
Lagerstroemia indica Crape Myrtle From China and Korea Huge variety of cultivars Best in mild climates that are not overly humid such as inland California and Texas
Crataegus phaenopyrum Washington Hawthorn
Crategus phaenopyrum Washington Hawthorn White to red flowers Dense growth Menacing thorns can make an inpenetrable hedge
Crategus phaenopyrum Washington Hawthorn Red pea-sized fruits are relished by birds. Can be cooked into jellies and jams.
Malus zumi Radiant Crabapple
Many different cultivars Hardier and more tolerant of wet soil than other stonefruit Most useful and least troublesome of flowering trees They can tolerate the heat
Spiraea japonica Goldflame
Spiraea japonica Glodflame New growth is bronze-red turning bright yellow, then eventually mid-green Dark pink flowers produced mid to late summer Easy to grow Enjoys sunny spot in moist well-drained soil