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SPECIES:  Rubus idaeus
American red raspberry. Image by Mary Ellen (Mel) Harte,



SPECIES: Rubus idaeus
AUTHORSHIP AND CITATION: Tirmenstein, D. 1990. Rubus idaeus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: []. Revisions: On 21 August 2018, the common name of this species was changed in FEIS from: red raspberry to: American red raspberry. Images were also added.
ABBREVIATION: RUBIDA SYNONYMS: R. idaeus subsp. sachalinensis (Levl.) Focke = R. i. subsp. strigosus NRCS PLANT CODE: RUID RUIDI RUIDS2 COMMON NAMES: American red raspberry black-haired red raspberry brilliant red raspberry raspberry red raspberry smoothleaf red raspberry wild raspberry wild red raspberry grayleaf raspberry TAXONOMY: The scientific name of American red raspberry is Rubus idaeus L. There are two subspecies [53]: Rubus idaeus subsp. idaeus, American red raspberry Rubus idaeus subsp. strigosus (Michx.) Focke, grayleaf raspberry Numerous American red raspberry hybrids have been reported, although many are infertile [43,104]. This shrub hybridizes with many species in the Rubus genus including R. arcticus, R. ursinus, R. occidentalis, R. rubrisetus, and R. odoratus [49,55,68,104]. American red raspberry has hybridized with thimbleberry (R. parviflorus) in the laboratory [49]. LIFE FORM: Shrub FEDERAL LEGAL STATUS: No special status OTHER STATUS: NO-ENTRY


SPECIES: Rubus idaeus
GENERAL DISTRIBUTION: American red raspberry occurs throughout most of the temperate regions of the world [20].  In North America it grows from Alaska through Canada to Newfoundland, southward to North Carolina and Tennessee in the East, and to Arizona, California, and northern Mexico in the West [36,93,98].  The native American red raspberry is Rubus idaeus subsp. strigosus [36]. R. i. subsp. idaeus grows across northern Europe to northwestern Asia [36].  It is cultivated in Hawaii [109] and throughout much of North America and has naturalized in many locations [36].
Distribution of American red raspberry in North America. Map courtesy of USDA, NRCS. 2018. The PLANTS Database. National Plant Data Team, Greensboro, NC [2018, August 21] [90].

   FRES10  White - red - jack pine
   FRES11  Spruce - fir
   FRES15  Oak - hickory
   FRES17  Elm - ash - cottonwood
   FRES18  Maple - beech - birch
   FRES19  Aspen - birch
   FRES20  Douglas-fir
   FRES21  Ponderosa pine
   FRES22  Western white pine
   FRES23  Fir - spruce
   FRES24  Hemlock - Sitka spruce
   FRES25  Larch
   FRES26  Lodgepole pine
   FRES28  Western hardwoods
   FRES34  Chaparral - mountain shrub
   FRES35  Pinyon - juniper
   FRES37  Mountain meadows
   FRES38  Plains grasslands
   FRES39  Prairie
   FRES44  Alpine

     AK  AL  AZ  AR  CA  CO  CT  DE  GA  HI
     ID  IL  IN  IA  KY  ME  MD  MA  MI  MN
     MO  MT  NV  NH  NJ  NM  NY  NC  ND  OH
     OR  PA  RI  SC  SD  TN  UT  VA  WA  WV
     WI  WY  AB  BC  MB  NB  NF  ON  PQ  SK

    1  Northern Pacific Border
    2  Cascade Mountains
    3  Southern Pacific Border
    5  Columbia Plateau
    8  Northern Rocky Mountains
    9  Middle Rocky Mountains
   10  Wyoming Basin
   11  Southern Rocky Mountains
   12  Colorado Plateau
   13  Rocky Mountain Piedmont
   14  Great Plains
   15  Black Hills Uplift
   16  Upper Missouri Basin and Broken Lands

   K001  Spruce - cedar - hemlock forest
   K002  Cedar - hemlock - Douglas-fir forest
   K004  Fir - hemlock forest
   K011  Western ponderosa forest
   K012  Douglas-fir forest
   K014  Grand fir - Douglas-fir forest
   K015  Western spruce - fir forest
   K016  Eastern ponderosa forest
   K017  Black Hills pine forest
   K018  Pine - Douglas-fir forest
   K020  Spruce - fir - Douglas-fir forest
   K021  Southwestern spruce - fir forest
   K023  Juniper - pinyon woodland
   K025  Alder - ash forest
   K037  Mountain mahogany - oak scrub
   K052  Alpine meadows and barren
   K064  Grama - needlegrass - wheatgrass
   K067  Wheatgrass - bluestem - needlegrass
   K074  Bluestem prairie
   K081  Oak savanna
   K093  Great Lakes spruce - fir forest
   K095  Great Lakes pine forest
   K096  Northeastern spruce - fir forest
   K097  Southeastern spruce - fir forest
   K098  Northern floodplain forest
   K102  Beech - maple forest
   K106  Northern hardwoods
   K107  Northern hardwoods - fir forest
   K108  Northern hardwoods - spruce forest

     1  Jack pine
     5  Balsam fir
    12  Black spruce
    13  Black spruce - tamarack
    15  Red pine
    16  Aspen
    17  Pin cherry
    18  Paper birch
    21  Eastern white pine
    22  White pine - hemlock
    25  Sugar maple - beech - yellow birch
    30  Red spruce - yellow birch
    31  Red spruce - sugar maple - beech
    32  Red spruce
    33  Red spruce - balsam fir
    35  Paper birch - red spruce - balsam fir
    37  Northern white cedar
    39  Black ash - American elm - red maple
    42  Bur oak
    60  Beech - sugar maple
   107  White spruce
   108  Red maple
   109  Hawthorn
   201  White spruce
   202  White spruce - paper birch
   204  Black spruce
   210  Interior Douglas-fir
   211  White fir
   212  Western larch
   213  Grand fir
   215  Western white pine
   217  Aspen
   218  Lodgepole
   222  Black cottonwood - willow
   224  Western hemlock
   226  Coastal true fir - hemlock
   227  Western redcedar - western hemlock
   228  Western redcedar
   229  Pacific Douglas-fir
   230  Douglas-fir - western hemlock
   235  Cottonwood - willow
   236  Bur oak
   237  Interior ponderosa pine
   239  Pinyon - juniper
   252  Paper birch
   253  Black spruce - white spruce
   254  Black spruce - paper birch

American red raspberry is well represented in many plant communities throughout
North America.  It grows within the understory of many quaking aspen
(Populus tremuloides), mixed conifer, cottonwood (Populus spp.), cedar
(Thuja spp.)-hemlock (Tsuga spp.), ponderosa pine (Pinus ponderosa),
spruce (Picea spp.)-fir (Abies spp.), and Douglas-fir (Pseudotsuga
menziesii) forests of the West [6,23,37].  In the Lake States and
Northeast, American red raspberry frequently grows in old-field communities, or in
association with jack pine (Pinus banksiana), white spruce (Picea
glauca), black spruce (P. mariana), red spruce (P. rubens), Atlantic
white-cedar (Thuja occidentalis), balsam fir (Abies balsamea), aspen
(Populus spp.), beech (Fagus spp.), maple (Acer spp.), red pine (Pinus
resinosa), and eastern white pine (P. strobus) [1,3,29,30,34,41,40,77].
It is a common component of northern hardwood forests and often assumes
dominance on sites which have been subject to windthrow, fire, or timber
harvest [100].  American red raspberry is a prominent component of many taiga
communities in Alaska [25] and the Canadian North.

Associated species:  American red raspberry grows with a wide variety of plants
across its extensive geographic range.  The following species are
particularly common plant associates [1,40,12,13,95]:  Canada beadruby
(Maianthemum canadense), thimbleberry, bunchberry (Cornus canadensis),
huckleberry (Vaccinium spp.), fireweed (Epilobium angustifolium),
bluejoint reedgrass (Calamagrostis canadensis), kinnikinnick
(Arctostaphylos uva-ursi), Virginia strawberry (Fragaria virginiana),
green alder (Alnus viridis subsp. crispa), twinflower (Linnaea borealis),
sedges (Carex spp.), prickly rose (Rosa acicularis), twinberry (Lonicera
spp.), lowbush blueberry (Vaccinium angustifolium), bog Labrador tea
(Ledum groenlandica), red currant (Ribes triste), highbush cranberry
(Viburnum edule), and red-osier dogwood (Cornus sericea).

American red raspberry occurs as a dominant in a number of plant communities.  It
has been included as a codominant in rocky, high elevation alpine scree
communities with Colorado columbine (Aquilegia coerulea) and
littleflower alumroot (Heuchera parvifolia).  American red raspberry has been
listed as an indicator or dominant member of a plant community in the
following publications:

Plant associations of Region Two: Potential plant communities of
  Wyoming, South Dakota, Nebraska, Colorado, and Kansas [51]
Habitat types on selected parts of the Gunnison and Uncompahgre National
  Forests [56]


SPECIES: Rubus idaeus
IMPORTANCE TO LIVESTOCK AND WILDLIFE: Raspberries provide food and cover for a wide range of wildlife species [10,100].  Some herbivores browse raspberry, but in general, it offers relatively poor forage.  American red raspberry is browsed by moose in Alaska but is not considered to be of primary importance [79].  In some locations, deer, rabbits, mountain beaver, and elk eat the foliage of raspberries [14,91].  Porcupine and beaver occasionally consume buds, twigs, or cambium of species within the genus Rubus [91].  However, thorns generally prevent excessive wildlife use of American red raspberry [95]. In general, raspberries have little forage value for domestic livestock [91]. Fruits of many species within the genus Rubus are eaten by ruffed grouse, blue grouse, sharp-tailed grouse, ring-necked pheasant, greater prairie chicken, California quail, northern bobwhite, gray catbird, northern cardinal, yellow-breasted chat, American robin, thrushes, towhees, brown thrasher, orchard oriole, summer tanager, pine grosbeak, gray (Hungarian) partridge, and band-tailed pigeon [14,91].  Mammals such as the coyote, raccoon, black bear, common opossum, squirrels, Townsend's chipmunk, skunks, red fox, and gray fox also seek out the fruits of many raspberries [14,91].  The eastern chipmunk, western chipmunk, deer mice, and grizzly bear consume American red raspberry fruit where available [59,105].  Flowers of American red raspberry provide nutritious food for bees [40]. PALATABILITY: American red raspberry browse appears to be relatively unpalatable to most ungulates.  However, the fruits are highly palatable to many birds and mammals.  The degree of use shown by livestock and wildlife species for American red raspberry is rated as follows [23]:                        CO       MT       ND       UT       WY Cattle                poor     poor     poor     fair     poor Sheep                 poor     fair     fair     good     fair Horses                poor     poor     poor     poor     poor Pronghorn             poor     ----     ----     poor     poor Elk                   ----     poor     ----     fair     fair Mule deer             ----     fair     ----     good     fair White-tailed deer     fair     ----     ----     ----     ---- Small mammals         good     ----     ----     good     fair Small nongame birds   poor     ----     ----     good     fair Upland game birds     ----     ----     ----     good     fair Waterfowl             ----     ----     ----     poor     poor   NUTRITIONAL VALUE: Browse:  American red raspberry browse is rated as poor in both energy and protein value [23].  Nitrogen, phosphorus, and potassium concentrations are highest in young leaves but decrease as leaves mature [46]. Conversely, calcium and magnesium concentrations are generally highest in mature leaves but lowest in young, developing leaves [46].  Zinc typically increases through the growing season whereas manganese decreases [46].  Levels of nitrogen, phosphorus, potassium, and calcium generally decline as the growing season progresses but may increase in the fall if additional rainfall allows plants to resume growth [46]. Fruit:  Raspberry fruits are sweet and contain relatively high amounts of both mono and disaccharides [88].  Relative glucose, starch, and sugar content has been documented for a number of American red raspberry cultivars [16]. COVER VALUE: Dense American red raspberry thickets serve as favorable nesting habitat for many small birds [14].  Small mammals such as rabbits and squirrels also find shelter in raspberry thickets [91].  The degree to which American red raspberry provides environmental protection during one or more seasons is rated as follows [23]:                       CO      UT      WY Pronghorn            ----    poor    poor Elk                  ----    poor    poor  Mule deer            ----    poor    poor White-tailed deer    ----    ----    poor   Small mammals        fair    fair    fair Small nongame birds  ----    fair    fair Upland game birds    ----    good    fair Waterfowl            ----    poor    poor VALUE FOR REHABILITATION OF DISTURBED SITES: Some ecotypes of American red raspberry have value in reclamation [95].  Suitable ecotypes are rated as having low to moderate value for short-term revegetation, and at least moderate value for long-term revegetation projects [23].  American red raspberry exhibits good potential for erosion control on some sites [10,91,95].  It has been successfully used to stabilize roadcuts and other disturbed sites in Utah and to revegetate bare soils in subalpine zones of Colorado [95].  American red raspberry is recommended for revegetation projects on well-drained sites in interior Alaska where maximum spacing of 3.3 feet by 3.3 feet (1 meter x 1 meter) is suggested [95].  Natural seedling establishment has been observed on many types of harsh sites, such as on tailings and surface soil of oil sand extraction plants in northern Alberta [95].  American red raspberry is capable of establishing on acidic tailings which have been treated with lime and on tar sands [95]. Propagation:  American red raspberry can be propagated through leaf bud cuttings, "rooted handles," stem cuttings, or root cuttings (suckers) [24,67,89,95].  Success of establishment through root cuttings varies according to the cultivar and planting date [89].  However, root cutting success has ranged up to 60 percent in experimental tests [89].  Correct choice of planting dates and techniques are important and significantly influence subsequent growth and establishment [14,89].  In vitro micropropagation techniques have also been developed for mass production of American red raspberry [97]. American red raspberry seedlings may be transplanted, or seed may be sown directly onto disturbed sites.  Seed which has been scarified can be successfully planted in the late summer or fall [10].  Cold treatment is not required for fall seedings.  Previously stratified and scarified seed can be planted in the spring [10].  Good results have been obtained after seeds were planted with a drill and covered with 1/8 to 3/16 inch (0.3-0.5 cm) of soil.  Cleaned seed averages approximately 328,000 per pound (722,467/kg) [10].  Detailed information is available on appropriate methods to obtain and plant American red raspberry seed [95]. OTHER USES AND VALUES: The American red raspberry was traditionally an important food of many Native American peoples.  It was eaten fresh or preserved for winter use [66]. Approximately 0.27 quarts (250 ml) of wild American red raspberry fruit can be hand-harvested within 30 minutes in good stands [66].  The fruit, bark of roots, and stems of raspberries have been used to make various medicinal preparations [10]. The unique edible fruit of the American red raspberry is delicious fresh or preserved.  Raspberries make excellent jams and jellies [93] and provide flavorful additions to pies and other baked goods, candies, and dairy products such as yogurt or ice cream.  Raspberry tea is commercially available and good although mild in flavor.  The raspberry industry in North America is a growing, multimillion dollar business [63].  Five primary regions produce most of the raspberries grown commercially in North America [63]:      1)  Northeast-Atlantic Provinces: southern Quebec through               Pennsylvania      2)  Central Atlantic Region:  Maryland to South Carolina, eastern               Kentucky and Tennessee, northern Georgia and Alabama      3)  Central Great Lakes Region:  Michigan, southern Ontario, Indiana,               Illinois, Ohio to Iowa, Missouri, western Kentucky and               Tennessee      4)  Prairie States Region:  Minnesota, southern Manitoba, eastern North                and South Dakota, and Wisconsin      5)  Pacific Northwest:  southern British Columbia, western Washington               and Oregon Cultivars:  Many cultivars have been developed to meet the needs of raspberry growers in a variety of climatic situations.  Most are derived from the European subspecies idaeus [98].  Desirable traits for red raspberry cultivars include spinelessness, winter hardiness, high fruit yields, resistance to disease, perennial stems, and primocane (or autumn) fruiting [49].  Reviews of particular cultivars document the extreme plasticity of this species and consider the suitability of each to various geographic locations [20,20,22,69,83,67,63,97,16,48]. Cultivars exhibit great genetic variation in time of flowerbud initiation, number of drupelets produced per fruit, time of fruit ripening, amount and timing of root suckering, length of dormancy, winter hardiness, fruit yield, and disease resistance [19,22,48,67,69,71,83,92].  Consequently, care should be taken to select cultivars with desirable traits which would enhance suitability for growth in a specific location [20].  The commonly cultivated loganberry may have been derived from a American red raspberry-trailing blackberry hybrid [17]. Commercial cultivation:  A wide array of studies detail commercial propagation of the American red raspberry.  Traditional techniques include hill culture of canes (stems), removal of weeds, and elimination of intercane suckers to increase fruit yield [64].  Older and weaker canes may be mowed or otherwise pruned annually to improve yield, enhance access to fruit, and to maintain the general health of the cane [67,102].  Trends in American red raspberry propagation include increasing mechanization [63]. Various cultivation techniques have been shown to improve fruit yields [16,65,72].  In some instances, application of nitrogen fertilizers can increase both cane growth and the number of flowers produced per node [67].  However, in other situations fertilizers appear to be of little benefit [33].  Following the addition of nitrogen fertilizer, Lawson and Waister [65] observed increased yields for two years, little effect during the third year, and decreased yields during the next two years. Similarly, irrigation appears to increase yields in some locations while having little effect elsewhere [72]. OTHER MANAGEMENT CONSIDERATIONS: Competition:  American red raspberry typically increases dramatically after fire or timber harvest [27,39].  In many areas this shrub can compete vigorously with conifer seedlings for light, moisture, nutrients, and space [30,34,62,74].  Dense thickets of American red raspberry reportedly suppress the growth of balsam fir (Abies balsamea) and spruce (Picea spp.) seedlings after spruce-fir forests of northern Maine are clearcut [30] and after timber harvest in the boreal forests of Ontario [82]. Raspberries also compete effectively with jack pine (Pinus banksiana) and red pine (P. resinosa) following timber harvest in northeastern Minnesota and Manitoba [3,74].  Graber and Thompson [34] observed that relatively few American red raspberry seeds are present within the soil of northeastern hardwood forest harvested at 100-year intervals.  However, in forests harvested at more frequent intervals, large numbers of red raspberry seed are present and massive simultaneous germination results in intense competition with conifer seedlings [34].   Chemical control:  American red raspberry is susceptible to a number of herbicides [9].  Glyphosate is commonly used as a mid-to-late summer foliar spray [82].  A number of herbicides have been suggested for use in reducing weeds in cultivated American red raspberry patches [8].


SPECIES: Rubus idaeus
GENERAL BOTANICAL CHARACTERISTICS: American red raspberry is a deciduous, erect or arching, thicket-forming shrub which grows from 1.6 to 9.8 feet (0.5-3 m) in height [36,80,86,93].  The total height and extent of growth is largely attributable to climatic factors [101].  Woody stems are bristly or prickly with shreddy, exfoliating yellow-brown bark [36,93].  Leaves are alternate and pinnately compound in leaflets of three to five [86,93].  Leaves are green and glabrous to hairy above but white or gray, hairy to glabrate and greenish beneath [98].  Small showy perfect white flowers are borne in clusters of one to four in a compound cyme [36,55,80,93]. Fruit of the American red raspberry is made up of many to several, red or pinkish-purple drupelets [80,98].  Aggregates of drupelets are commonly referred to as a "berry." American red raspberry is made up of mostly biennial canes (stems) on a long-lived perennial rootstock [45,99].  This rootstock initially forms from seedling establishment or the production of root suckers [99], which gradually separate from parent plants as the connecting root tissue dies [45].  Sterile first-year stems, or primocanes, develop from buds at or below the ground surface and generally bear only leaves [36,99].  During the second year, lateral branches, known as floricanes, develop in the axils of the primocanes which produce both leaves and fruit [36,100].  A "typical" raspberry rootstock system is made up of at least one floricane and several primocanes [99].  It should be noted that some commercially grown strains of American red raspberry are primocane-fruiting; that is, they are capable of bearing fruit during the fall of the first year of development [21,92].  Primocane-fruiting appears to be absent entirely or represents an atypical situation in native-growing populations of American red raspberry. RAUNKIAER LIFE FORM: Hemicryptophyte REGENERATION PROCESSES: American red raspberry reproduces through seed and also regenerates vegetatively. It is capable of forming dense thickets through sprouting.  Reproductive versatility is well represented in the Rubus genus, with sexual reproduction, parthenogenesis (development of the egg without fertilization), pseudogamy (a form of apomixis in which pollination is required), and parthenocarpy (production of fruit without fertilization) occurring widely [17].  The following types of reproduction have been documented within the genus:  (1) sexual reproduction, (2) nonreduction at meiosis on the female, male, or both sides, (3) apomixis with segregation, (4) apomixis without segregation, and (5) haploid parthenogenesis [17].  These modes of asexual reproduction are important because they help contribute to the vigorous, aggressive spread of red raspberry. American red raspberry is capable of vigorous sprouting after disturbance [18] but also expands in clonal area through vegetative regeneration [95,100].  Natural vegetative regeneration occurs through root sprouts or "suckers" [95,100,101], "stolons" [95], "rhizomes" [39,52], and basal stem buds or root crowns [45,95,101].  The precise mode of vegetative regeneration depends on the type and severity of disturbance.  Dense raspberry thickets form from the roots or stems of parent plants which separate to form individual plants with the deterioration of connecting tissue [45].  American red raspberry allocates most energy to vegetative regeneration on recently disturbed sites with favorable growing conditions [99].  With time, initially elevated nutrient levels decline, and shading increases.  As growing conditions deteriorate, American red raspberry shifts its reproductive effort to the production of large numbers of seed [39,100]. American red raspberry sprouts readily from portions of aboveground stems which survive disturbance [52].  Many raspberry species are capable of rooting from the stem nodes, and layering has been widely reported in the red raspberry [95].  This shrub is also capable of sprouting from axillary buds located "well above the ground level" [45].  Root crown or stembase sprouting is an important regenerative mode, which in the raspberry gives rise to biennial stems even in the absence of disturbance [36,45]. American red raspberry typically sprouts from the root crown if aerial foliage is cut late in the growing season [95].  In related species such as salmonberry (R. spectabilis), apical dominance exerted by extant root crowns inhibits sprouting from belowground structures such as roots or rhizomes [106]. Root "suckering" is a normal, on-going process in American red raspberry stands [45,101].  However, particularly vigorous root suckering is often observed after the aboveground vegetation is damaged or destroyed.  This shrub regenerates from buds located on the larger main roots as well as those present on lateral roots which are often located fairly close to the soil surface [52,101].  The mean depth of these underground regenerative structures (root buds) was estimated at 2.4 inches (6 cm) in a New Brunswick study [28].  During the first 2 to 3 years after establishment, root suckers fill in spatial gaps in the clone [100]. Root sucker mortality is generally high during the third and fourth years because of intense intraspecific competition for sunlight, space, and nutrients which result in "self thinning" of stands [45,100]. Suckering ability declines with age, with production decreasing from an average of 1.5 per square foot (16.0/sq m) in 3-year-old stands to 0.77 per square foot (8.25/sq m) in 4-year-old stands [100].  Although relatively few root suckers actually reach the canopy, survival rates of those that do is high [100].  Most root suckers live for only 1 or 2 months [100].  Several researchers report that American red raspberry is capable of sprouting from rhizomes after fire or other disturbance [39,52]. However, others have observed that American red raspberry lacks rhizomes with any regenerative capability [28].  The term "rhizome" may have been loosely applied to rhizomelike roots which do possess the ability to sprout. Geographic or genetic differences in American red raspberry morphology and physiology are also possible. Seed:  Immature fruit, commonly referred to as "berries," are pink and hard [10].  Ripe fruit is generally red, but less commonly white or yellow [43].  Several to many small individual drupelets form an aggregate fruit [10,98].  Fruit size appears to be related to soil moisture [72], although significant genotypic variation has also been noted in the size and number of fruits produced annually [22]. Decreased stored nutrient availability and water stress can influence overall fruit production [16].  It is estimated that 70 to 90 percent of American red raspberry flowers eventually mature into fruit which results in an abundance of seed [99].  Whitney [100] observed that 77 percent of all plants flowered, with 85 percent of those flowering producing seed. Most species of raspberry produce good seed crops nearly every year [10], but seed production does vary annually in the American red raspberry according to climatic factors and the age of the cane.  Whitney [100] observed average seed production of 65 seeds per square foot (700 seeds/ sq m) in 2-year-old canes, with maximum production of 1,301 seeds per square foot (14,000 seeds/sq m) in 4-year-old canes.  Annual seed production averaged 604 seeds per square foot (6,500 seeds/sq m) over a 4-year period [100]. Pollination:  American red raspberry is primarily pollinated by bees, although flies and beetles also pollinate some flowers [40].  Under natural conditions, it is almost exclusively self-incompatible [55] which contributes to morphological variability. Germination:  Seed of the American red raspberry is relatively large [31], with viability averaging up to 92 to 99 percent in laboratory tests [95].  Red raspberry seeds have a hard, thick, impermeable coat and dormant embryo [10].  Seeds have the ability to become dormant a second time in response to environmental factors [50].  Consequently, germination is often slow.  Most raspberry seeds require, as a minimum, warm stratification at 68 to 86 degrees F (20 to 30 degrees C) for 90 days, followed by cold stratification at 36 to 41 degrees F (2 to 5 degrees C) for an additional 90 days [10].  Cold stratification alone is insufficient to induce germination in American red raspberry [59].  Laboratory tests indicate that exposure to sulfuric acid solutions or sodium hyperchlorite prior to cold stratification can improve germination [10,43,50,95].  Evidence suggests that the digestive enzymes of mammals can also enhance germination, with seeds eaten by chipmunks and deer mice exhibiting better germination than untreated seeds [59].  Sowing seeds at greater depths with subsequent exposure to light can produce better germination than shallow plantings, presumably because of greater soil moisture [50].  Results of specific germination tests have been documented in a number of studies [10,50,59]. Seed banking:  American red raspberry amasses large numbers of seed which persist in the soil until favorable germination conditions are encountered [31,35,100].  Often, many seeds remain buried in the soil of stands which lack any sign of the parent plants [31].  American red raspberry seed can remain viable for 60 to 100 years or more [62,73,100].  Seeds are less likely to germinate when fresh [50,62], and may reach maximum viability at 50 to 100 years of age [34].  In a New Hampshire study, approximately 90 percent of Rubus (R. idaeus and R. alleghaniensis) seed germinated during the first summer after disturbance in 38-, 95-, and > 200-year-old stands, whereas only 60 percent of those in 5-year-old stands germinated [34].  More than 4,048,583 Rubus seeds per acre (10 million/ha) have been found in the soil of 5-year-old beech (Fagus spp.)-birch (Betula spp.)-maple (Acer spp.) stands [34].  Numbers declined to 48,588 per acre (120,000/ha) in 200-year-old stands [34]. Annual reductions in stored seed have been attributed to: (1) degeneration resulting in death, (2) fungi or animal predation, and (3) annual germination of some seeds.  Fyles [31] reported 237 to 1,883 seeds per foot square (22-175/m sq) in organic soil and 0 to 2,582 per foot square (0-240 m sq) in mineral soil of upland coniferous forests of central Alberta.  Distribution of germinating seeds by stand age in beech-birch-maple forests of New Hampshire were as follows [34]:                            stand age in years                           5       38        95        200 + #seeds/m sq.            1,016    286        68        12 Seed dispersal:  American red raspberry seed is readily dispersed by birds and mammals [87,100].  After they mature, the highly sought-after fruit rarely remains on the plants for long [10].  Birds have been observed to deposit 2,429 to 2,834 viable seeds per acre (6,000 to 7,000/ha) annually in beech-birch-maple forests of New Hampshire [34].  Mammals such as mice and chipmunks may be important dispersal agents in some areas [59]. Seedling establishment:  Most seedlings germinate during the first year after disturbance [99,100] and produce stands which are primarily even aged.  In many instances, as much as 70 to 90 percent of all individuals establish during the first year after disturbance [100]. Researchers have observed minimal recruitment in the second, third, and fourth years after fire [100].  Little seedling establishment occurs beneath the shade of a closed forest canopy [100]. SITE CHARACTERISTICS: American red raspberry grows across a wide range of sites throughout most of the world's temperate regions [20].  It commonly occurs in clearings or borders in boreal forests, in ravines, on bluffs and streambanks of prairie regions, and on talus or scree above timberline [39,86,93,95]. Soil:  Raspberries are tolerant of a wide range of soil pH and texture but do require adequate soil moisture [14].  American red raspberry grows on imperfectly to well-drained sandy loam to silty clay loam, but best growth occurs on moderately well-drained soils [95].  Although red raspberry grows well on barren and infertile soils, it reportedly has a relatively high demand for soil nutrients and is most abundant on nutrient-rich soils [39].  This shrub is moderately tolerant of acidic soils [95]. Elevation:  Generalized elevational ranges for selected locations are as follows [23,98]:                from 6,500 to 11,700 feet (1,981 to 3,569 m) in CO                     2,400 to 7,000 feet (732 to 2,134 m) in MT                     5,500 to 9,600 feet (1,676 to 3,420 m) in UT                     6,500 to 11,000 feet (1,981 to 3,355 m) in WY SUCCESSIONAL STATUS: American red raspberry vigorously invades and colonizes many types of disturbed sites [62,95,100].  It is generally considered a pioneer or early seral species [35] which flourishes and completes its life cycle during the first years after disturbance [100].  This shade-intolerant species often dominates sites during early successional stages but decreases as the canopy closes [62,100].  Although the plants themselves remain prominent for only a relatively brief period, viable seeds can persist for 60 years or more in the soil or duff [73].  Widespread germination after disturbance frequently leads to the development of even-aged stands [100].  In many areas, American red raspberry is absent beneath the canopy of mature forests but persists in forest openings [39].  Whitney [99] reports that few stands of American red raspberry persist for longer than 5 to 12 years. American red raspberry invades black and white spruce stands in Alaska during the first years after disturbance but declines as taller shrubs and trees become established [29,39].  In many northern black spruce forests, red raspberry is present only in early successional stages [29].  On mesic and submesic sites in sub-boreal forests of British Columbia it typically increases during the first 10 years after timber harvest or fire but is virtually eliminated within 14 years because of rapid increases in shade [39].  American red raspberry often dominates jack pine stands of Minnesota within 5 years after disturbance [2,39] and subsequently declines as the canopy develops.  In parts of western Montana, red raspberry initially grows rapidly but begins to decline within 3 to 4 years after disturbance as nutrient levels decrease [18].  American red raspberry can persist for up to 4 or 5 years in northern hardwood forests as long as stands remain relatively open [47,73].  In birch-maple forests of New Hampshire, American red raspberry reaches peak abundance in the second through fourth years after disturbance [100].  However, it rarely persists for more than 10 years [100].  American red raspberry is subsequently replaced by species such as aspen, chokecherry (Prunus spp.), and birch [100]. SEASONAL DEVELOPMENT: American red raspberry is typically biennial, with each shoot passing through well-defined phenological stages during its 2-year lifespan [45]. Vegetative shoots develop from the roots or stems of parent plants, or as seedlings, during the first year [45,99,100,101].  Lateral flowering stalks (floricanes) are produced during the second year [22,99,100]. Floricanes leaf out early and exhibit rapid growth [99].  After producing fruit in late summer, the leaves of floricanes senesce and the cane gradually dies [99].  Stages of the 2-year growth cycle of red raspberry are detailed below [45]:                                                     YEAR 1        Phases               phase 1:  initiation of root buds                  phase 2:  subterranean suckering           phase 3:  emergent suckers; elongation slows or stops           as sucker reaches surface; leaves form a rosette           at or above the soil surface. phase 4:  1st winter dormancy-most leaves shed                                 YEAR 2 phase 5:  elongating shoot; rapid elongation.      phase 6:  initiation of flower buds; shoot stops             elongation at end of growing season.            secondary rosettes form; axillary meristems           initiate flower primordia; dormant fruit buds;           leaves become senescent and fall. phase 7:  breaking dormancy of flower buds; require           cold to break dormancy; buds grow in spring           (some cultivars produce fruit before dormancy). phase 8:  flowering and fruiting; basal buds elongate           into a vegetative replacement shoot which           repeats the biennial cycle. phase 9:  senescence and death.  (after fruiting the           shoot dies back "to the position from which           a replacement shoot has grown"). Flowering:  Flowerbud initiation is influenced by temperature, genetics (cultivar), and geographic location [21,48,69,92].  Flowering is also related to the age and vigor of the plant and the date at which vegetative growth terminates [16,67].  Flowerbud initiation is triggered by low temperatures and short days and generally begins in late summer or autumn [16,21].  Flowerbud initiation can be induced by exposure to temperatures of 55 degrees F (12.8 degrees C) at 9 hour days or 50 degrees F (10.0 degrees C) at 16 hour days [21].  Although flowerbud initiation occurs over winter in most red raspberries, initiation in primocane-fruiting cultivars begins in summer [92].  Bud break typically occurs in early spring [16].  Evidence suggests that higher spring temperatures may promote earlier and more rapid flowering [67]. Fruiting:  Fruit maturation begins soon after flowering [88].  Timing of flowerbud initiation largely determines fruiting season [21], although fruiting dates also vary according to cultivar and geographic location [21].  Annual variation in fruit ripening has also been reported [21]. Both flowering and fruiting proceeds from the top of the floricane downward [22].  After maturation, fruit spoils rapidly [88]. Generalized fruiting and flowering dates by geographic location are as follows [21,23,36,54,80,84,86,88,93]:      location        flowering             fruiting        AK            June-July             July-September        AZ            June-July             -----        BC            -----                 July-August        CO            June-July             -----      East            -----                 July-October  Great Plains        May-July              -----        MT            June-August           -----     NC, SC           June-August           July-August (or later)        ND            June                  -----   New England        ----                  late June-August   nc Plains          June-July             July-August        UT            May-July              -----        WY            June-August           -----


SPECIES: Rubus idaeus
FIRE ECOLOGY OR ADAPTATIONS: The life cycle of American red raspberry is integrally associated with disturbances such as fire.  In many areas of vigorous fire suppression, both plant vigor and abundance have decreased [66].  American red raspberry typically flourishes, completes its life cycle and declines within the early years after disturbance [73].  As shade levels increase in the postfire community and soil nitrate levels drop (generally during the first 5 years after fire), American red raspberry shifts resource allocation from vegetative growth to seed production [39,99]. Although the plants themselves soon senesce and die, viable seed persists for decades [62,73], germinating in great numbers after the next fire [100] creates favorable conditions for growth and establishment.  Seed is effectively scarified by heat [78,94], and exposed mineral soil serves as a favorable substrate for early growth and development [26].  Underground regenerative structures appear to be well protected from the damaging effects of heat [28,52], and reestablishment is typically rapid where plants were present in the preburn community. FIRE REGIMES: Find 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". POSTFIRE REGENERATION STRATEGY:    Tall shrub, adventitious-bud root crown    Rhizomatous shrub, rhizome in soil    Geophyte, growing points deep in soil    Ground residual colonizer (on-site, initial community)    Initial-offsite colonizer (off-site, initial community)


SPECIES: Rubus idaeus
IMMEDIATE FIRE EFFECT ON PLANT: American red raspberry is described as "resistant" to fire [39,103].  However, foliage is extremely susceptible to fire-induced mortality [52].  In an Alberta study, all aboveground stems were completely killed wherever supplemental fuels contributed to relatively intense fires [52].  Where fuels were reduced and fires less intense, the stems of many plants were only partially killed [52].  However, all aerial stems experienced at least partial mortality, regardless of fire intensity. Belowground regenerative structures appear to be relatively resistant to fire [39].  Johnston and Woodard [52] observed belowground mortality only on plots with high surface fuel loadings (3.94 or 9.65 kg/m sq). Here, tissue mortality extended as far as 0.4 to 1.2 inches (1-3 cm) below the duff surface.  Raspberry is capable of sprouting from lateral buds on relatively shallow roots.  These roots, which are small and succulent, are poorly protected by duff and can be damaged by fires of high intensity and severity [52].  However, at least some regenerative structures typically grow to 2 inches (5 cm) below the soil surface, and many are apparently unharmed by fires of even high intensity and severity [52].  In general, the effects of fire on American red raspberry are much less pronounced wherever nutrients and water are abundant [39]. The long-lived seed of American red raspberry is generally unharmed by fire when protected by overlying soil [39,78,94]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT: In an Alberta study, both dead and live woody stems remained where fuel loadings of 0.00, 0.17, and 0.87 kg/m sq were recorded [52].  However, all foliage was completely consumed on plots with fuel loadings of 3.94 and 9.65 kg/m sq [52]. PLANT RESPONSE TO FIRE: American red raspberry is well adapted to reoccupy a site quickly after fire. This common "fire follower" is favored by increased amounts of nitrates present on burned sites and generally exhibits rapid and vigorous postfire growth through sprouting and/or seedling establishment [4,95]. Vegetative response:  American red raspberry typically sprouts readily after fire wherever present in preburn communities [18,95].  Most belowground regenerative structures appear to be well protected from the damaging effects of heat [52].  Postfire sprouting of root buds is commonly observed.  Although more shallow root buds may be damaged or killed by heat, root bud depths can range from 1.9 to 2.4 inches (5-6 cm) or greater [28,52] and many escape serious damage.  Postfire sprouting from rhizomes may also occur [39], although a number of researchers have reported no evidence of any rhizomes with regenerative capabilities in the American red raspberry [28].  Where light fires damage but do not kill the aboveground foliage, aerial stems generally sprout and quickly resume growth [52].  Consequently, American red raspberry is reported to be "rejuvenated" by fire [103]. Johnston and Woodard [52] reported that fire intensity and severity had little effect on the sprouting ability of American red raspberry in aspen communities of east-central Alberta.  Both the number of sprouts produced per plant and total biomass appeared unaffected by fire intensity and severity.  However, the height growth of individual sprouts was greatest after fires of low severity.  Thus, although high severity fires reduced the rate of sprout growth, they did not affect the number of sprouts produced by each plant [52]. Seedling establishment:  Rapid postfire establishment through on-site seed is common in the American red raspberry [95].  Long-lived seed, which is produced in abundance, accumulates in seed banks in the soil or duff [35,38].  Germination is enhanced by exposure to heat [78,94], and large numbers of seed germinate soon after disturbance [100].  Mineral soil creates a favorable seedbed [26] and elevated nitrate levels enhance early seedling growth.  Most germination occurs within the first year after fire [38].  Limited evidence suggests that fires of high intensity and severity may promote American red raspberry seedling establishment more than light fires. Bock and Bock [6] observed vigorous seedling establishment after crown fires in ponderosa pine forest of the southern Black Hills.  However, large increases in American red raspberry did not occur after lighter, cooler ground fires in the same area [6,7].  Extremely light fires may provide insufficient heat scarification and do little to prepare a seedbed. Postfire recovery:  Postfire recovery of American red raspberry is generally rapid, with vigorous expansion in cover during early seral stages.  This shade-intolerant species [95,100] declines as tree cover increases [29]. In many communities, American red raspberry begins to decline within only 3 or 4 years after fire [18,103].  It is important to note that many variables can significantly influence the speed of postfire recovery and subsequent persistence within the community.  Such variables may include season of burn, fire intensity and severity, site characteristics, genetic variation, and climatic factors.  Specific postfire response of American red raspberry by community is discussed in the 'Successional Status' slot. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE: In some areas, significant differences in postfire recovery of red raspberry have been noted after fires of varying intensity and severity. The following data document postfire recovery in ponderosa pine stands of the southern Black Hills of South Dakota [7,6]: ------------------------------------------------------------------------                   # of stems per subplot fire type       preburn     1st year     2nd year      5th year   light burn       0            0          0.07         ---   crown fire      ---          ---         0.01        116.8                        # of individuals fire type               1st year     2nd year     3rd year     5th year   cool ground fire          0            0           3           ---   hot crown fire           ---          ---         ---         4,672 ------------------------------------------------------------------------     For further information on American red raspberry response to fire, see Fire Case Studies. Hamilton's Research Papers (Hamilton 2006a, Hamilton 2006b) also provide information on prescribed fire and postfire response of plant community species, including American red raspberry, that was not available when this species review was originally written. FIRE MANAGEMENT CONSIDERATIONS: Fire generally benefits animals that consume the fruits of species within the genus Rubus [58].


SPECIES: Rubus idaeus
FIRE CASE STUDY CITATION: Tirmenstein, D., compiler. 1990. Effects of prescribed fire on American red raspberry on Elk Island, Alberta. In: Rubus idaeus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: []. REFERENCE: Johnston, Mark; Woodard, Paul. 1985. The effect of fire severity level on postfire recovery of hazel and raspberry in east-central Alberta. Canadian Journal of Botany. 63: 672-677. [52]. SEASON/SEVERITY CLASSIFICATION: May 5, 1980/variable STUDY LOCATION: The study site is located in Elk Island National Park, approximately 23 miles (37 km) east of Edmonton, Alberta. PREFIRE VEGETATIVE COMMUNITY: Preburn overstory vegetation was made up of quaking aspen (Populus tremuloides) and balsam poplar (P. balsamifera), which ranged from 50 to 70 years of age.  Understory vegetation was dominated by American red raspberry (Rubus idaeus), beaked hazelnut (Corylus cornuta), strawberry (Fragaria spp.), fleabane (Erigeron spp.), and reedgrass (Calamagrostis spp.). TARGET SPECIES PHENOLOGICAL STATE: not reported. SITE DESCRIPTION:      Soil - orthic gray luvisol      Elevation - not reported      Topography - not reported      Size of treated area - 9.9 acres (4 ha)      Weather conditions - dry FIRE DESCRIPTION: Seven artificial fuel beds (24 x 24 inches [60 x 60 cm]) were constructed of varying amounts of excelsior, or excelsior mixed with white spruce slats.  The prescribed head fire did not spread to the beds because of discontinuous fuels.  The beds were ignited with matches after the passage of the flame front.  Specific weather and fire behavior characteristics were as follows:      Fire weather:      Dry bulb temperature (C) - 14.5      Relative humidity (%) - 33      Wind speed at 10 m (kh/h) - 6      Fine fuel moisture code - 88      Duff moisture code - 57      Drought code - 106      Initial spread index - 4      Buildup index - 58      Fire weather index - 12      Estimated fire behavior characteristics recorded for the seven      fuel beds ignited with matches -           fuel loading     flame length     frontal fire     residence time      (kg/m sq.)       (m)              intensity        (minutes)                                        (kW/m)      0.17             0.5                  57            1.5      0.87             1                   258            2      0.87             1                   258            2      3.94             1.5                 622            4      3.94             1.5                 622            4      9.65             1.5               1,162           10      9.65             2.5               1,905           10     FIRE EFFECTS ON TARGET SPECIES: All aboveground American red raspberry stems were killed where fuels were added. On fuel-free plots, only portions of the aboveground stems were killed. Plants sprouted from underground regenerative structures where aboveground mortality was complete, but from both aboveground and belowground tissues where portions of the aerial stems were killed. Depth of underground regenerative structures ranged from 0 to 2 inches (0-5 cm), with mortality of tissues occasionally extending to 0.4 to 1.2 inches (1-3 cm) below the duff surface.  Portions of most deeper "rhizomes" apparently survived.  American red raspberry also reproduces through lateral buds located on small, shallow, succulent, poorly protected roots which can be damaged by fires of high intensity. The number of sprouts produced per plant did not vary according to burn treatment.  Height growth and the number of leaves did vary by treatment, indicating that American red raspberry recovery may be affected by fire intensity and severity.  Specific recovery rate data for red raspberry were as follows:   date     response                     fuel loading (kg/m sq.)            parameter              0.00    0.17    0.87    3.94    9.65   July 4   #sprouts/plot          5       4       4       4       5            ht. growth/sprout(cm)  52.0    32.7    17.4    12.2    8.8            avg. # leaves/sprout   --      8       6       5       3   July 22  #sprouts/plot          6       4       5       4       7            ht. growth/sprout(cm)  58.7    36.5    19.5    16.1    12.8            avg. # leaves/sprout   --      8       6       5       5   Aug. 1   #sprouts/plot          3       4       4       4       7            ht. growth/sprout(cm)  58.4    36.8    19.1    16.2    13.5            avg. # leaves/sprout   --      8       6       5       5   Aug. 16  #sprouts/plot          3       4       5       4       7            ht. growth/sprout(cm)  60.0    37.2    21.0    16.7    13.5            avg. # leaves/sprout   --      7       7       6       6   Aug. 30  #sprouts/plot          3       2       4       3       7            ht. growth/sprout(cm)  60.2    37.0    20.8    16.8    13.8            avg. # leaves/sprout   --      7       6       5       6 Mean abovegrd. ovendry biomass            (grams/plot)           2.5     4.1     5.0     4.6     4.4 FIRE MANAGEMENT IMPLICATIONS: American red raspberry may be somewhat susceptible to high intensity fires because of shallow, fairly poorly protected root buds.  This study suggests that hot prescribed fires may be useful in reducing red raspberry in some carefully selected instances.


SPECIES: Rubus idaeus
REFERENCES: 1.  Ahlgren, Clifford E. 1959. Some effects of fire on forest reproduction        in northeastern Minnesota. Journal of Forestry. 57: 194-200.  [208] 2.  Ahlgren, Clifford E. 1966. Small mammals and reforestation following        prescribed burning. Journal of Forestry. 64: 614-618.  [206] 3.  Ahlgren, Clifford E. 1976. Regeneration of red pine and white pine        following wildfire and logging in northeastern Minnesota. Journal of        Forestry. 74: 135-140.  [7242] 4.  Ahlgren, I. F.; Ahlgren, C. E. 1960. Ecological effects of forest fires.        Botanical Review. 26: 458-533.  [205] 5.  Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals,        reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's        associations for the eleven western states. Tech. Note 301. Denver, CO:        U.S. Department of the Interior, Bureau of Land Management. 169 p.        [434] 6.  Bock, Jane H.; Bock, Carl E. 1984. Effects of fires on woody vegetation        in the pine-grassland ecotone of the southern Black Hills. American        Midland Naturalist. 112(1): 35-42.  [477] 7.  Bock, Jane H.; Bock, Carl E. [n.d.]. Some effects of fire on vegetation        and wildlife in ponderosa pine forests of the southern Black Hills.        Final Report. Contracts CX-1200-9-B034, CX-1200-0-B018, CX-1200-1-B022;        Grant No. RM-80-105 GR. Unpublished report on file with: U.S. Department        of Agriculture, Forest Service, Intermountain Research Station, Fire        Sciences Lab, Missoula, MT. 58 p.  [479] 8.  Bonanno, A. Richard                                             .x.        1987. Raspberry and blackberry weed management in Michigan. In: 117th        annual report, Michigan State Horticulture Society: 177-182.  [7059] 9.  Bovey, Rodney W. 1977. Response of selected woody plants in the United        States to herbicides. Agric. Handb. 493. Washington, DC: U.S. Department        of Agriculture, Agricultural Research Service. 101 p.  [8899] 10.  Brinkman, Kenneth A. 1974. Rubus L.  blackberry, raspberry. In:        Schopmeyer, C. S., ed. Seeds of woody plants in the United States.        Agriculture Handbook No. 450. Washington, DC: U.S. Department of        Agriculture, Forest Service: 738-743.  [7743] 11.  Chrosciewicz, Z. 1976. Burning for black spruce regeneration on a        lowland cutover site in southeastern Manitoba. Canadian Journal of        Forest Research. 6(2): 179-186.  [7280] 12.  Chrosciewicz, Z. 1978. Slash and duff reduction by burning on clear-cut        jack pine sites in central Saskatchewan. Information Report NOR-X-200.        Edmonton, AB: Forestry Service, Fisheries and Environment Canada,        Northern Forest Research Centre. 12 p.  [7288] 13.  Chrosciewicz, Z. 1978. Large-scale operational burns for slash disposal        and conifer reproduction in central Saskatchewan. Information Report        NOR-X-201. Edmonton, AB: Forestry Service, Fisheries and Environment        Canada, Northern Forest Research Centre. 11p.  [7289] 14.  Core, Earl L. 1974. Brambles. In: Gill, John D.; Healy, William M.,        compilers. Shrubs and vines for Northeastern wildlife. Gen. Tech. Rep.        NE-9. Broomall, PA: U.S. Department of Agriculture, Forest Service:        16-19.  [8923] 15.  Corns, Ian G. W. 1989. Ecosystems with potential for aspen management.        Managing for aspen--a shared responsibility: Proceedings of the Joint        TechnicalSession of the Forest Ecology, Silviculture and Tree        Improvement Forest Management, and Forest Economics and Policy Working        Groups; September 1988; Prince Albert, SK. In: The Forestry Chronicle.        February: 16-22.  [6919] 16.  Crandall, P. C.; Allmendinger, D. F.; Biderbost, K. A. 1974. Influence        of cane number and diameter, irrigation, and carbohydrate reserves on        the fruit number of red raspberries. Journal of the American        Horticultural Society. 99(6): 524-526.  [6652] 17.  Crane, M. B. 1940. Reproductive versatility in Rubus. I. Morphology and        inheritance. Journal of Genetics. 40: 109-118.  [8443] 18.  Crane, Marilyn F. 1982. Fire ecology of Rocky Mountain Region forest        habitat types. Final Report Contract No. 43-83X9-1-884. Missoula, MT:        U.S. Department of Agriculture, Forest Service, Region 1. 272 p. On file        with: U.S. Department of Agriculture, Forest Service, Intermountain        Research Station, Fire Sciences Laboratory, Missoula, MT.  [5292] 19.  Dale, A. 1979. Varietal differences in the relationships between some        characteristics of red raspberry fruiting laterals and their position on        the cane. Journal of the Horticultural Society. 54(4): 257-265.  [6983] 20.  Dale, Adam; Daubeny, Hugh A. 1985. Genotype-environmental interactions        involving British and Pacific Northwest red raspberry cultivars.        HortScience. 20(1): 68-69.  [6834] 21.  Dale, Adam; Daubeny, Hugh A. 1987. Flower-bud initiation in red        raspberry (Rubus idaeus L.) in two environments. Crop Research. 27:        61-66.  [6980] 22.  Dale, A.; Topham, Pauline B. 1980. Fruiting structure of the red        raspberry:  multivariate analysis of lateral characteristics. Journal of        the Horticultural Society. 55(4): 397-408.  [6982] 23.  Dittberner, Phillip L.; Olson, Michael R. 1983. The plant information        network (PIN) data base: Colorado, Montana, North Dakota, Utah, and        Wyoming. FWS/OBS-83/86. Washington, DC: U.S. Department of the Interior,        Fish and Wildlife Service. 786 p.  [806] 24.  Doran, William L. 1957. Propagation of woody plants by cuttings.        Experiment Station Bul. No. 491. Amherst, MA: University of        Massachusetts, College of Agriculture. 99 p.  [6399] 25.  Dyrness, C. T.; Viereck, L. A.; Van Cleve, K. 1986. Fire in taiga        communities of interior Alaska. In: Forest ecosystems in the Alaskan        taiga. New York: Springer-Verlag: 74-86.  [3881] 26.  Dyrness, C. T.; Viereck, L. A.; Foote, M. J.; Zasada, J. C. 1988. The        effect on vegetation and soil temperature of logging flood-plain white        spruce. Res. Pap. PNW-RP-392. Portland, OR: U.S. Department of        Agriculture, Forest Service, Pacific Northwest Research Station. 45 p.        [7471] 27.  Eyre, F. H., ed. 1980. Forest cover types of the United States and        Canada. Washington, DC: Society of American Foresters. 148 p.  [905] 28.  Flinn, Marguerite A.; Wein, Ross W. 1977. Depth of underground plant        organs and theoretical survival during fire. Canadian Journal of Botany.        55: 2550-2554.  [6362] 29.  Foote, M. Joan. 1983. Classification, description, and dynamics of plant        communities after fire in the taiga of interior Alaska. Res. Pap.        PNW-307. Portland, OR: U.S. Department of Agriculture, Forest Service,        Pacific Northwest Forest and Range Experiment Station. 108 p.  [7080] 30.  Fox, Thomas R. 1986. Raspberry (Rubus idaeus L.) competition effects on        balsam fir (Abies balsamea (L.) Mill.) seedlings in northern Maine. Tree        Planter's Notes. 37(2): 20-23.  [6825] 31.  Fyles, James W. 1989. Seed bank populations in upland coniferous forests        in central Alberta. Canadian Journal of Botany. 67: 274-278.  [6388] 32.  Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others].        1977. Vegetation and environmental features of forest and range        ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of        Agriculture, Forest Service. 68 p.  [998] 33.  Goode, J. E. 1970. Nitrogen nutrition and susceptibility of Malling        Jewel raspberries to infection by spur blight (Didymella applanata).        Plant Pathology. 19: 108-110.  [6591] 34.  Graber, Raymond E.; Thompson, Donald F. 1978. Seeds in the organic        layers and soil of four beech-birch-maple stands. Res. Pap. NE-401.        Broomall, PA: U.S. Department of Agriculture, Forest        Service,Northeastern Forest Experiment Station. 8 p.  [5983] 35.  Granstrom, Anders. 1982. Seed banks in five boreal forest stands        originating between 1810 and 1963. Canadian Journal of Botany. 60:        1815-1821.  [5940] 36.  Great Plains Flora Association. 1986. Flora of the Great Plains.        Lawrence, KS: University Press of Kansas. 1392 p.  [1603] 37.  Haeussler, S.; Pojar, J.; Geisler, B. M.; [and others]. 1985. A guide to        the interior cedar-hemlock zone, northwestern transitional subzone        (ICHg), in the Prince Rupert Forest Region, British Columbia. Land        Management Report Number 26; ISSN 0702-9861. Victoria, BC: British        Columbia, Ministry of Forests. 263 p.  [6930] 38.  Hamilton, Evelyn H. 1988. Impacts of prescribed burning on        soil-vegetation relationships in the sub-boreal spruce zone. In: Feller,        M. C.; Thomson, S. M., eds. Wildlife and range prescribed burning        workshop proceedings; 1987 October 27-28; Richmond, BC. Vancouver, BC:        The University of British Columbia, Faculty of Forestry: 171-184.        [3110] 39.  Bare, B. Bruce. 1982. The economics of true fir management. In: Oliver,        Chadwick Dearing; Kenady, Reid M., eds. Proceedings of the biology and        management of true fir in the Pacific Northwest symposium; 1981 February        24-26; Seattle-Tacoma. Contribution No. 45. Seattle, WA: University of        Washington, College of Forest Resources: 9-14.  [6760] 40.  Hansen, Richard W.; Osgood, Eben A. 1983. Insects visiting flowers of        wild red raspberry in spruce-fir forested areas of eastern Maine.        Entomological News. 94(4): 147-151.  [7001] 41.  Hansen, H. L.; Krefting, L. W.; Kurmis, V. 1973. The forest of Isle        Royale in relation to fire history and wildlife. Tech. Bull. 294;        Forestry Series 13. Minneapolis, MN: University of Minnesota,        Agricultural Experiment Station. 44 p.  [8120] 42.  Hansen, Paul L.; Hoffman, George R.; Steinauer, Gerry A. 1984. Upland        forest and woodland habitat types of the Missouri Plateau, Great Plains        Province. In: Noble, Daniel L.; Winokur, Robert P., eds. Wooded draws:        characteristics and values for the Northern Great Plains: Symposium        proceedings; 1984 June 12-13; Rapid City, SD. Great Plains Agricultural        Council Publ. No. 111. Rapid City, SD: South Dakota School of Mines and        Technology, Biology Department: 15-26.  [1078] 43.  Heit, C. E. 1967. Propagation from seed. Part 7: Germinating six        hardseeded groups. American Nurseryman. 125(12): 10-12; 37-41; 44-45.        [1120] 44.  Hogdon, A. R.; Steele, Frederic. 1966. Rubus subgenus Eubatus in New        England: a conspectus. Rhodora. 68: 474-513.  [6213] 45.  Hudson, J. P. 1959. Effects of environment on Rubus idaeus L.  I.        Morphology and development of the raspberry plant. Journal of        Horticultural Science. 34: 163-169.  [6607] 46.  Hughes, Megan; Chaplin, M. H.; Dixon, A. R. 1979. Elemental composition        of red raspberry leaves as a function of time of season and position on        cane. HortScience. 14(1): 46-47.  [6833] 47.  Hughes, Jeffrey W.; Fahey, Timothy J.; Bormann, F. Herbert. 1988.        Population persistence and reproductive ecology of a forest herb: Aster        acuminatus. American Journal of Botany. 75(7): 1057-1064.  [8972] 48.  Jennings, D. L.; Cormack, M. R. 1969. Factors affecting the water        content and dormancy of overwintering raspberry canes. Horticultural        Research. 9: 18-25.  [6655] 49.  Jennings, D. L.; Ingram, Ruth. 1983. Hybrids of Rubus parviflorus        (Nutt.) with raspberry and blackberry, and the inheritance of        spinelessness derived from this species. Crop Research. 23(2): 95-101.        [7029] 50.  Jennings, D. L.; Tulloch, M. M. 1964. Studies on factors which promote        germination of raspberry seeds. Journal of Experimental Botany. 16(47):        329-340.  [6535] 51.  Johnston, Barry C. 1987. Plant associations of Region Two: Potential        plant communities of Wyoming, South Dakota, Nebraska, Colorado, and        Kansas. 4th ed. R2-ECOL-87-2. Lakewood, CO: U.S. Department of        Agriculture, Forest Service, Rocky Mountain Region. 429 p.  [3519] 52.  Johnston, Mark; Woodard, Paul. 1985. The effect of fire severity level        on postfire recovery of hazel and raspberry in east-central Alberta.        Canadian Journal of Botany. 63: 672-677.  [6277] 53.  Kartesz, John T. 1994. A synonymized checklist of the vascular flora of        the United States, Canada, and Greenland. Volume II--thesaurus. 2nd ed.        Portland, OR: Timber Press. 816 p.  [23878] 54.  Kearney, Thomas H.; Peebles, Robert H.; Howell, John Thomas; McClintock,        Elizabeth. 1960. Arizona flora. 2d ed. Berkeley, CA: University of        California Press. 1085 p.  [6563] 55.  Keep, Elizabeth. 1968. Incompatibility in Rubus with special reference        to R. idaeus L. Canadian Journal of Genetic Cytology. 10: 253-262.        [6654] 56.  Komarkova, Vera. 1986. Habitat types on selected parts of the Gunnison        and Uncompahgre National Forests. Final Report Contract No. 28-K2-234.        Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky        Mountain Forest and Range Experiment Station. 270 p.  [1369] 57.  Kooiman, Marianne; Linhart, Yan B. 1986. Structure and change in        herbaceous communities of four ecosystems in the  Front Range, Colorado,        U.S.A. Arctic and Alpine Research. 18(1): 97-110.  [4076] 58.  Kramp, Betty A.; Patton, David R.; Brady, Ward W. 1983. The effects of        fire on wildlife habitat and species. RUN WILD: Wildlife/ habitat        relationships. Albuerque, NM: U.S. Department of Agriculture, Forest        Service, Southwestern Region, Wildlife Unit Technical Report. 29 p.        [152] 59.  Krefting, Laurits W.; Roe, Eugene I. 1949. The role of some birds and        mammals in seed germination. Ecological Monographs. 19(3): 269-286.        [8847] 60.  Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation        of the conterminous United States. Special Publication No. 36. New York:        American Geographical Society. 77 p.  [1384] 61.  Larsen, J. A. 1929. Fires and forest succession in the Bitterroot        Mountains of northern Idaho. Ecology. 10: 67-76.  [6990] 62.  Lautenschlager, R. A. 1987. Interactions among red rapsberries and        northern forest trees. Proceedings of the Annual Meetings Northeastern        Weed Science Soc. 41: 186-187.  [7007] 63.  Lawrence, F. J. 1980. The current status of red raspberry cultivars in        the United States and Canada. Fruit Varieties Journal. 34(4): 84-89.        [6984] 64.  Lawson, H. M.; Waister, P. D. 1972. The effects of soil cultivation        techniques on the growth and yield of the raspberry crop. Weed Research.        12: 96-106.  [6604] 65.  Lawson, H. M.; Waister, P. D. 1972. The response to nitrogen of a        raspberry plantation under contrasting systems of management for weed        and sucker control. Horticultural Research. 12: 43-55.  [6653] 66.  Lepofsky, Dana; Turner, Nancy J.; Kuhnlein, Harriet V. 1985. Determining        the availability of traditional wild plant foods: an example of Nuxalk        foods, Bella Coola, British Columbia. Ecology of Food and Nutrition. 16:        223-241.  [7002] 67.  Lockshin, L. S.; Elfving, D. C. 1981. Flowering response of 'Heritage'        red raspberry to temperature and nitrogen. HortScience. 16(4): 527-528.        [6824] 68.  Longley, Albert E. 1924. Cytological studies in the genus Rubus.        American Journal of Botany. 11: 249-282.  [6249] 69.  Luby, J. J.; Hoover, E. E.; Bedford, D. S.; Munson, S. T.; Gray, W. H.;        Wildung, D. K.; Stushnoff, C. 1987. 'Redwing' raspberry. HortScience.        22(4): 681-682.  [2957] 70.  Lyon, L. Jack; Stickney, Peter F. 1976. Early vegetal succession        following large northern Rocky Mountain wildfires. In: Proceedings, Tall        Timbers fire ecology conference and Intermountain Fire Research Council        fire and land management symposium; 1974 October 8-10; Missoula, MT. No.        14. Tallahassee, FL: Tall Timbers Research Station: 355-373.  [1496] 71.  Mackenzie, K. A. D. 1979. The structure of the fruit of the red        raspberry (Rubus idaeus L.) in relation to abscission. Annals of Botany.        43(3): 355-362.  [6822] 72.  MacKerron, D. K. L. 1982. Growth and water use in the red raspberry        (Rubus idaeus L.) I.  Growth and yield under differenct levels of soil        moisture stress. Journal of Horticultural Science. 57(3): 295-306.        [6979] 73.  Marks, P. L. 1974. The role of pin cherry (Prunus pensylvanica L.) in        the maintenance of stability in northern hardwood ecosystems. Ecological        Monographs. 44: 73-88.  [4144] 74.  McRae, D. J. 1979. Prescribed burning in jack pine logging slash: a        review. Report 0-X-289. Sault Ste. Marie, ON: Canadian Forestry Service,        Great Lakes Forest Research Centre. 57 p.  [7290] 75.  Munz, Philip A. 1973. A California flora and supplement. Berkeley, CA:        University of California Press. 1905 p.  [6155] 76.  Ohmann, Lewis F.; Ream, Robert R. 1971. Wilderness ecology: virgin plant        communities of the Boundary Waters Canoe Area. Res. Pap. NC-63. St.        Paul, MN: U.S. Department of Agriculture, Forest Service, North Central        Forest Experiment Station. 55 p.  [9271] 77.  Ohmann, Lewis F.; Cushwa, Charles T.; Lake, Roger E.; [and others].        1973. Wilderness ecology: the upland plant communities, woody browse        production, and small mammals of two adj. 33-year-old wildfire areas in        northeastern Minnesota. Gen. Tech. Rep. NC-7. St. Paul, MN: U.S.        Department of Agriculture, Forest Service, North Central Forest        Experiment Station. 30 p.  [6862] 78.  Parminter, John. 1983. Fire history and fire ecology in the Prince        Rupert Forest region. In: Trowbridge, R. L.; Macadam, A., eds.        Prescribed fire--forest soils: Symposium proceedings; 1982 March 2-3;        Smithers, BC. Land Management Report Number 16. Victoria, BC: Province        of British Columbia, Ministry of Forests: 1-35.  [8849] 79.  Peek, J. M. 1974. A review of moose food habits studies in North        America. Le Naturaliste Canadien. 101: 195-215.  [7420] bsp;      the vascular flora of the Carolinas. Chapel Hill, NC: The University of        North Carolina Press. 1183 p.  [7606] 81.  Raunkiaer, C. 1934. The life forms of plants and statistical plant        geography. Oxford: Clarendon Press. 632 p.  [2843] 82.  Roy, D. N.; Konar, S. K.; Banerjee, S.; [and others]. 1989. Uptake and        persistence of the herbicide glyphosate (Vison) in fruit of wild        blueberry and red raspberry. Canadian Journal of Forestry. 19: 842-847.        [8907] 83.  Sanford, J. C.; Ourecky, D. K.; Reich, J. E. 1985. 'Titan' red        raspberry. HortScience. 20(6): 1133-1134.  [6832] 84.  Seymour, Frank Conkling. 1982. The flora of New England. 2d ed.        Phytologia Memoirs 5. Plainfield, NJ: Harold N. Moldenke and Alma L.        Moldenke. 611 p.  [7604] 85.  Siccama, T. G. 1974. Vegetation, soil, and climate on the Green        Mountains of Vermont. Ecological Monographs. 44: 325-249.  [6859] 86.  Stephens, H. A. 1973. Woody plants of the North Central Plains.        Lawrence, KS: The University Press of Kansas. 530 p.  [3804] 87. Sundance Forest Fire, northern Idaho. Gen. Tech. Rep. INT-197. Ogden,        UT: U.S. Department of Agriculture, Forest Service, Intermountain        Research Station. 26 p.  [2255] 88.  Stiles, Edmund W. 1980. Patterns of fruit presentation and seed        dispersal in bird-disseminated woody plants in the Eastern deciduous        forest. American Naturalist. 116(5): 670-688.  [6508] 89.  Torre, Louis C.; Barritt, Bruce H. 1979. Red raspberry establishment        from root cuttings. Journal of the American Society for Horticultural        Science. 104(1): 28-31.  [7028] 90.  U.S. Department of Agriculture, Natural Resources Conservation Service. 2018. PLANTS Database, [Online]. U.S. Department of Agriculture, Natural Resources Conservation Service (Producer). Available:  [34262] 91.  Van Dersal, William R. 1938. Native woody plants of the United States,        their erosion-control and wildlife values. Washington, DC: U.S.        Department of Agriculture. 362 p.  [4240] 92.  Temperature and development of red raspberry flower buds. Journal of the        American Horticultural Society. 104(1): 61-62.  [6976] 93.  Viereck, Leslie A.; Little, Elbert L., Jr. 1972. Alaska trees and        shrubs. Agric. Handb. 410. Washington, DC: U.S. Department of        Agriculture, Forest Service. 265 p.  [6884] 94.  Viereck, Leslie A.; Schandelmeier, Linda A. 1980. Effects of fire in        Alaska and adjacent Canada--a literature review. BLM-Alaska Tech. Rep.        6. Anchorage, AK: U.S. Department of the Interior, Bureau of Land        Mangement, Alaska State Office. 124 p.  [7075] 95.  Watson, L. E.; Parker, R. W.; Polster, D. F. 1980. Manual of plant        species suitablity for reclamation in Alberta. Vol. 2. Forbs, shrubs and        trees. Edmonton, AB: Land Conservation and Reclamation Council. 537 p.        [8855] 96.  Weber, M. G. 1987. Decomposition, litter fall, and forest floor nutrient        dynamics in relation to fire in eastern Ontario jack pine ecosystems.        Canadian Journal of Forest Research. 17: 1496-1506.  [7240] 97.  Welander, Margareta. 1985. In vitro culture of raspberry (Rubus idaeus)        for mass propagation. Journal of Horticultural Science. 60(4): 493-499.        [6981] 98.  Welsh, Stanley L.; Atwood, N. Duane; Goodrich, Sherel; Higgins, Larry        C., eds. 1987. A Utah flora. Great Basin Naturalist Memoir No. 9. Provo,        UT: Brigham Young University. 894 p.  [2944] 99.  Whitney, Gordon G. 1982. The productivity and carbohydrate economy of a        developing stand of Rubus idaeus. Canadian Journal of Botany. 60:        2697-2703.  [6534] 100. Whitney, Gordon G. 1986. A demographic analysis of Rubus idaeus and        Rubus pubescens. Canadian Journal of Botany. 64: 2916-2921.  [120] 101. Williams, I. H. 1959. Effects of environment on Rubus idaeus L.  II.        Field observations on the variety Malling Promise. Journal of        Horticultural Science. 34: 170-175.  [6606] 102. Williamson, B.; Lawson, H. M.; Woodford, J. A. T.; Hargreaves, A. J. ;        [and others].. 1979. Vigour control, an integrated approach to cane,        pest and disease management in red raspberry (Rubus idaeus). Annal of        Applied Biology. 92: 359-368.  [6536] 103. Wright, Henry A. 1973. Fire as a tool to manage tobosa grasslands. In:        Proceedings--annual tall timbers fire ecology conference; 1972 June 8-9;        Lubbock, TX. Number 12. Tallahassee, FL: Tall Timbers Research Station:        153-167.  [2612] 104. Yarnell, S. H. 1936. Chromosome behavior in blackberry-raspberry        hybrids. Journal of Agricultural Research. 52(5): 385-396.  [6201] 105. Zager, Peter Edward. 1980. The influence of logging and wildfire on        grizzly bear habitat in northwestern Montana. Missoula, MT: University        of Montana. 131 p. Dissertation.  [5032] 106. Zasada, John; Tappeiner, John; Maxwell, Bruce. 1989. Manual treatment of        Salmonberry or which bud's for you?. Cope Report, Coastal Oregon        Productivity Enhancement Program. 2(2): 7-9.  [7060] 107. Stickney, Peter F. 1989. Seral origin of species originating in northern        Rocky Mountain forests. Unpublished draft on file at: U.S. Department of        Agriculture, Forest Service, Intermountain Research Station, Fire        Sciences Laboratory, Missoula, MT; RWU 4403 files. 7 p.  [20090] 108. U.S. Department of the Interior, National Biological Survey. [n.d.]. NP        Flora [Data base]. Davis, CA: U.S. Department of the Interior, National        Biological Survey.  [23119] 109. St. John, Harold. 1973. List and summary of the flowering plants in the        Hawaiian islands. Hong Kong: Cathay Press Limited. 519 p.  [25354]

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