SPECIES: Symphoricarpos longiflorus
© 1997 Larry Blakely
AUTHORSHIP AND CITATION:
McWilliams, Jack D. 2005. Symphoricarpos longiflorus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/ .
NRCS PLANT CODE :
The currently accepted scientific name for longflower snowberry is Symphoricarpos longiflorus Gray (Caprifoliaceae) [11,22,24,57,58]. There are no recognized varieties or forms.
Because of the paucity of specific information on longflower snowberry, some
reference is made to the genus of snowberries (Symphoricarpos spp.) in
FEDERAL LEGAL STATUS:
Plants database provides a distributional map of longflower snowberry.
The following lists include North American ecosystems, habitat types, and
forest and range cover types in which longflower snowberry may occur. These
lists are not necessarily exhaustive or completely inclusive. More information
is needed regarding areas where longflower snowberry may be part of the flora.
FRES21 Ponderosa pine
FRES30 Desert shrub
FRES34 Chaparral-mountain shrub
STATES/PROVINCES: (key to state/province abbreviations)
In a description of northern Nevada sagebrush plant associations, Zamora and Tueller  list plants occurring with longflower snowberry. Shrubs occurring with longflower snowberry in northern Nevada include low sagebrush (A. arbuscula), big sagebrush (A. tridentata), fringed sagebrush (A. frigida), black sagebrush (A. nova), green rabbitbrush (Chrysothamnus viscidiflorus), antelope bitterbrush (Purshia tridentata), and gray horsebrush (Tetradymia canescens). Grasses associated with longflower snowberry in northern Nevada are bluebunch wheatgrass (Pseudoroegneria spicata), Sandberg bluegrass (Poa secunda), and Idaho fescue (Festuca idahoensis).
Issacson  lists Saskatoon serviceberry (Amelanchier alnifolia), curlleaf mountain-mahogany (Cercocarpus ledifolius), and Idaho fescue as plants associated with longflower snowberry in the pinyon-juniper woodlands of central Nevada and Utah.
Classifications describing plant communities in which longflower snowberry is a dominant species are:
Longflower snowberry is a native, perennial shrub mostly 20 to 39 inches (50-100
cm) tall . Low spreading branches 20 to 39 inches (50-100 cm) long  are
commonly spread at right angles to the stem . Older branches become fibrous and
shreddy , and smaller twigs tend to persist so plants may be "somewhat thorny"
. The deciduous leaves are simple and opposite . Perfect flowers  are solitary
or paired in leaf axils, or in small, terminal, few-flowered racemes  and produce
a berry-like drupe with 2 nutlets
RAUNKIAER  LIFE FORM:
Information concerning regeneration of longflower snowberry is scant. Vines  states longflower snowberry can be propagated by seeds. Bradley and others  describe longflower snowberry has having a root crown and rhizomes that sprout after fire. Presumably, sprouting would occur after other forms of disturbance.
McArthur and others  state all species of snowberry establish readily from seed and cuttings from wild plants and that plants spread rapidly by layering.
Breeding system: Snowberries produce perfect flowers  so are considered monoecious.
Pollination: No information is available on this topic.
Seed production: No information is available on this topic.
Seed dispersal: There are no direct references to seed dispersal of longflower snowberry in the available literature as of this writing (2005). The seeds of longflower snowberry are eaten by birds, especially the gallinaceous birds such as ring-necked pheasants, grouse, and quail . In a study of western snowberry (S. occidentalis), Pelton  concluded that "at least some" of western snowberry nutlets would survive passing through the digestive system of birds, so birds could act as seed dispersal agents. Since the nutlets of longflower snowberry are similar to those of western snowberry, birds likely play a part in seed dispersal of longflower snowberry. McArthur and others  state mice and other small rodents cache seeds of snowberries, and plants are widely established from these caches .
Since snowberries produce drupes as a fruit, it is reasonable to assume wind plays little role in longflower snowberry seed dispersal. Pelton , in a discussion of western snowberry, states, "Wind is probably of very minor importance in dispersal."
Seed banking: There is no information in the literature concerning longflower snowberry and seed banking. Snowberries in general have a tough seed coat and a partially developed embryo, which sometimes delays germination . This delay in germination may provide a small, temporary seed bank. Morgan and Neuenschwander  reported finding seeds of both common snowberry (S. albus) and creeping snowberry (S. mollis) in the seed bank after clearcutting and broadcast burning in northern Idaho. The authors comment that seeds of neither species had been reported in previous seed bank studies.
Germination: As of this writing (2005), there is no information available concerning germination of longflower snowberry seeds. Stanton  discusses germination of mountain snowberry (S. oreophilus), a plant very similar to longflower snowberry, and states mountain snowberry has a seed germination rate of 67% to 78%.
Seedling establishment/growth: No information is available on this topic.
Bradley and others  state longflower snowberry has a root crown and rhizomes that sprout after
fire. Additionally, all species of snowberry spread rapidly by
Longflower snowberry has narrow ecological boundaries and is usually found on xeric sites . Longflower snowberry is common on dry, rocky soils in desert areas of southern Utah . In the White Mountains of California, longflower snowberry occurs on granitic substrate at an elevation from 9,500 to 10,000 feet (2,896-3,048 m) .
Reported elevational ranges for longflower snowberry in some states where it occurs are:
|Arizona||4,000 to 8,000 feet (1,219-2,498 m)|||
|California||4,429 to 5,249 feet (1,350-1,600 m)|||
|4,500 to 10,000 feet (1,392-3,048 m)|||
|Colorado||about 5,000 feet (1,524 m)|||
|Nevada||3,800 to 7,500 feet (1,158-2,286 m)|||
|New Mexico||6,000 to 8,000 feet (1,829-2,438 m)|||
|Texas||5,000 to 6,500 feet (1,524-1,981 m)|||
|Utah||3,002 to 9,514 feet (915-2,900 m)|||
Stanton  describes the minimum mean annual precipitation for longflower
snowberry occurrence as 8 to 9 inches (203-229 mm).
Bradley and others  describe postfire successional patterns in late-successional juniper woodlands in western Utah, and longflower snowberry is listed as an understory shrub in these woodlands. After fire the shrub stage of succession occurs in mid- to late-seral development but before the late-successional stage of a closed juniper woodland.
Flowering dates for longflower snowberry are:
|Arizona||April to August |
|Nevada||May to June |
|New Mexico||May to August |
|Texas||May to August [42,57]|
Fire regimes: Bradley and others  place longflower snowberry within a fire group in Utah that consists of late-successional stands dominated by pinyon, juniper or both. In the presettlement era, fire was a relatively common event in pinyon-juniper stands. Fire increased productivity of understory species like longflower snowberry. Specific fire history studies of pinyon-juniper are few, with none focusing on Utah, but the literature contains studies of fire history of pinyon-juniper stands in other areas.
Leopold  suggests fire occurred at intervals of 10 to 30 years for Colorado pinyon-alligator juniper (P. edulis-J. deppeana) in Arizona. On 4 study sites in the climax western juniper (J. occidentalis) stands of southwestern Idaho, fire-free intervals were 23, 18, 8, and 11 years between the years 1840 and 1910 . Moir  believed that Mexican pinyon (P. cembroides) stands in the Chisos Mountains of Texas could be maintained in a "natural" condition by fire occurring every "50 years or so."
The following list provides fire return intervals for plant communities and ecosystems where longflower snowberry is important. It may not be inclusive. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes".
|Community or Ecosystem||Dominant Species||Fire Return Interval Range (years)|
|silver sagebrush steppe||Artemisia cana||5-45 [19,43,61]|
|sagebrush steppe||Artemisia tridentata/Pseudoroegneria spicata||20-70 |
|basin big sagebrush||Artemisia tridentata var. tridentata||12-43 |
|mountain big sagebrush||Artemisia tridentata var. vaseyana||15-40 [2,9,34]|
|Wyoming big sagebrush||Artemisia tridentata var. wyomingensis||10-70 (40**) [56,64]|
|California montane chaparral||Ceanothus and/or Arctostaphylos spp.||50-100 |
|curlleaf mountain-mahogany*||Cercocarpus ledifolius||13-1,000 [3,47]|
|mountain-mahogany-Gambel oak scrub||Cercocarpus ledifolius-Quercus gambelii||< 35 to < 100|
|blackbrush||Coleogyne ramosissima||< 35 to < 100|
|western juniper||Juniperus occidentalis||20-70|
|Rocky Mountain juniper||Juniperus scopulorum||< 35|
|pinyon-juniper||Pinus-Juniperus spp.||< 35 |
|Mexican pinyon||Pinus cembroides||20-70 [35,53]|
|Colorado pinyon||Pinus edulis||10-400+ [15,17,26,39]|
|Jeffrey pine||Pinus jeffreyi||5-30 |
|interior ponderosa pine*||Pinus ponderosa var. scopulorum||2-30 [1,4,30]|
|Arizona pine||Pinus ponderosa var. arizonica||2-15 [4,10,48]|
|oak-juniper woodland (Southwest)||Quercus-Juniperus spp.||< 35 to < 200 |
|interior live oak||Quercus wislizenii||< 35 |
Longflower snowberry is browsed by deer and livestock and the seeds are eaten by birds, especially the gallinaceous birds such as ring-necked pheasants, grouse and quail . Sage-grouse in Nevada utilize longflower snowberry as both juveniles and adults . The American pika and various ground squirrels also eat the seeds .
Kufeld and others  provide a literature review of plants utilized by Rocky Mountain mule deer. Longflower snowberry is used "lightly" in all seasons but winter, when it is not utilized. Limited summer use of longflower snowberry by pronghorns in Utah has been observed .Palatability/nutritional value: Longflower snowberry is considered "largely unpalatable" to livestock in the desert regions of Nevada and Utah , and is rated as fair in both energy and protein content . Plummer and others  give palatability of longflower snowberry an overall rating of fair, a winter rating of poor, summer rating of fair, and a spring rating of very good in a discussion of shrubs used in restoring Utah big game range.
Cover value of longflower snowberry for big game is limited by its size
(see General Botanical Characteristics).
However, it provides fair cover for both upland game birds and small nongame birds and good cover
for small mammals in Utah . It is reasonable to assume that longflower snowberry provides this
same cover value for birds and small mammals in other areas where it occurs.
VALUE FOR REHABILITATION OF DISTURBED SITES:
Longflower snowberry has limited range (see General Distribution) with relatively narrow environmental constraints (see Site Characteristics). Within these limits longflower snowberry is "vitally important" for rehabilitation of disturbed sites because no substitute with similar attributes has been found . McArthur and others  describe longleaf snowberry as having the same adaptive attributes as mountain snowberry but in more xeric sites. These attributes include erosion control on roadcuts and fills as well as mine spoils, especially in pinyon-juniper sites in Utah and Nevada. Plummer and others  also describe longflower snowberry as having the same adaptive properties as mountain snowberry.
Vines  states longflower snowberry can be propagated by seeds and softwood or hardwood cuttings.
McArthur and others  state all species of snowberry establish readily from seed, wildings, and nursery
stock and that plants spread rapidly by layering.
There is little in the available literature concerning alternative uses of longflower snowberry. McArthur and others  state snowberries are well suited as an ornamental on roadsides and recreational areas.
OTHER MANAGEMENT CONSIDERATIONS:
The fruit of longflower snowberry contains saponin, but in such small quantities that poisoning rarely occurs .
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