• GENERAL BOTANICAL CHARACTERISTICS
• RAUNKIAER LIFE FORM
• REGENERATION PROCESSES
• SITE CHARACTERISTICS
• SUCCESSIONAL STATUS
• SEASONAL DEVELOPMENT

GENERAL BOTANICAL CHARACTERISTICS:

Oceanspray is a native, deciduous, spreading shrub 3 to 20 feet (1-6 m) tall with slender arching branches [40,67,108]. It can range from bushy individuals only 2.5 feet (0.75 m) tall to arborescent coastal forms which may reach heights of approximately 20 feet (6.1 m). Most plants, however, typically grow from 3 to 10 feet (1-3 m) in height [27,53]. The leaves are ovate to ovate-elliptic or oblong, mostly 1.6 to 2.75 inches (4-7 cm) long, and 0.8 to 2.75 inches (2-7 cm) wide with 15 to 25 shallow lobes to deep teeth with prominent veins [108,67]. Oceanspray is a moderately shade tolerant shrub. Flowers form large drooping branched clusters and often persist on branches well into the autumn [40]. Flowers are borne on large, showy, terminal panicles that may reach up to 12 inches (30 cm) in length [10]. The common name oceanspray is derived from these masses of loose, creamy plumes [25].

Oceanspray is host to some saprophytic species. In southwestern British Columbia, oceanspray was found to be a primary host for vesicular-arbuscular mycorrhizae [10] and pine broomrape (Orobanche pinorum), an obligate root parasite, that receives its entire complement of water and nutrition from its host [46].  

RAUNKIAER [91] LIFE FORM:

Phanerophyte

REGENERATION PROCESSES:

Oceanspray produces small, hairy, 1-seeded fruit [66], and preburn regeneration of this species is primarily by wind dispersal of the light seed [114]. Postburn regeneration occurs primarily by root crown sprouts, but may also occur by soil-stored seed [13,103,111,114,82].

An eastern Washington and eastern Oregon study found that production of oceanspray was greatest for heavily clipped (75 to 100%) plants compared with moderately and slightly clipped plants. Much of the new growth was in the form of long, unbranched water sprouts or suckers, originating at various places along the sides of old stems and branches. Clipping, however, suppressed flower production [37]. According to the Wind River Nursery, oceanspray propagates by follicle seed type collected during the summer and stratified on a warm/cool cycle. Stratification of seed in either sand or peat at 41 degrees Fahrenheit (5 ^oC) for 18 weeks appears to be optimum for breaking the dormant condition [101] in an artificial setting. The seeds are then planted in nursery beds in the fall [45].

Although information indicates that postburn seedling establishment is rare [114,82], a northern Idaho study determined oceanspray to be an important early seral shrub species that relies on seedbanks of the forest floor for postburn regeneration. The greatest regenerated seedling covers were found in areas of severe burns and originated from seed in duff and soil seedbanks [77]. Oceanspray in the Oregon Coast Range germinated well (>70%) in both clearcuts and young, unthinned conifer stands; however, survival occurred only in the young stands [105].  

SITE CHARACTERISTICS:

Widely distributed throughout the Pacific Northwest, oceanspray occupies a variety of sites ranging from moist, coastal bluffs and mountains to the dry, coniferous forest types of the Intermountain region [101,52]. Oceanspray occurs mostly in dry environmental zones, from sea level to 5500 feet (1676 m) elevation [66], and exists primarily at the hot, dry end of the moisture gradient in the Pacific Northwest forest complexes [36,87,41,66,108,48,40]. Soils are usually shallow and stony [52,35,51] and have a relatively high pH of 5.8 to 6.8 [80]. This species has an apparent affinity for southern slopes which are usually warmer and drier [80,35,51]; however, rehabilitation of western Oregon clearcuts by oceanspray occurred only on the northern slopes [113].

A grand fir (Abies grandis)/oceanspray association in southwestern Washington is common on exposed, south-facing slopes on either ridgetops or on adjacent steep slopes. Sites having this association remain snow-free much of the year and experience extreme summer drought [107]. The Douglas-fir/oceanspray association in the Oregon Coastal Range most often occurs on relatively steep, south or west facing slopes between 2000-3000 feet (600-900 m) elevation. Soils are generally thin and rocky or deep, heavy clay. The overall environment is hot and dry and the growing season is long with a substantial drought developing by mid-summer. Snowpacks are not generally deep or persistent [48]. A western hemlock-Douglas-fir/oceanspray association is found in some of the hottest and driest sites in the forested western Cascade Mountains. Sites are "always" upper slopes and fairly steep, where drainage and solar input are "excessive." Bare ground and surface rock and gravel are also typical and soils are shallow and stony [44]. Oceanspray has a higher probability of occurring following timber harvest in grand fir or western redcedar (Thuja plicata) than in the western hemlock habitat type [54].

Sites in which oceanspray is commonly found include the following:

Location	Annual Precip.	Elevation	Reference
western WA	57 in (1440 mm)	722 ft (220 m)	[69]
central OR	9.3 in (236 mm)	2400 ft (732 m)	[29]
west-central OR	na	1601 ft (488 m)	[112]
southern OR	41 in (1041 mm)	2543 ft (775 m)	[106]
western CA	20 in (510 mm)	na	[41]
northern ID	36 in (915 mm)	4400 ft (1341 m)	[20]

SUCCESSIONAL STATUS:

Oceanspray occurs in many successional stages. In Glacier Park's cedar-hemlock forests, oceanspray is restricted to climax communities [42], and it is a late successional species in northern Idaho's hemlock habitat types [115]. Following the Sundance fire in northern Idaho, oceanspray was a secondary cover species of the 1st decade's seral vegetation [102]. After shrubfield burns, this shrub regenerates readily from seeds and underground parts, and after approximately 10 years, most of the herbaceous species decline as dense shrub cover develops [100]. Oceanspray is found in approximately 5-fold higher density in immature stands (less than 150 years old) than in old growth stands (greater than 150 years old) in mesic, coniferous forest in northwestern Montana [7]. The individual plants rarely live for more than 30 years [5].

According to the following data, the highest percent coverage of oceanspray occurs approximately 20 years after a disturbance and then declines. Oceanspray was found in five Douglas-fir/salal (Gaultheria shallon) stands in the Cascade Mountain foothills of Washington [69]. The percentage of ground cover of this species is as follows:

SEASONAL DEVELOPMENT:

Oceanspray is usually among the first shrubs to initiate leaves in mid-April on brushfield sites in northern Idaho. Stem elongation begins in mid-May and continues until the end of June [83]. Perfect flower buds appear early in spring, but full flowering does not occur until June or July and may continue in some areas into August [52]. In the northern Rocky Mountains, the flowering period occurs during the middle or latter part of July, with fruit ripening in late August and seed being dispersed from then until the end of November. Change in leaf color usually occurs near the end of September in northern Idaho [83].

Related categories for SPECIES: Holodiscus discolor | Oceanspray