Fraser Fir Research Articles

Applying Diagnosis and Recommendation Integrated System to Fraser Fir Christmas Trees

Fraser fir [Abies fraseri (Pursh) Poir.] is responsive to nutrient additions. Christmas tree growers are attempting to take advantage of this responsiveness in order to produce higher quality and therefore more valuable trees. The Diagnosis and Recommendation Integrated System (DRIS) was applied to this tree crop to assess its usefulness for diagnosing nutrient needs. Of 12 tree attributes, basal diameter at a given age proved to be the best substitute for yield in DRIS calculations. The basal diameter used to separate highand low-quality populations was 30 mm for trees in 3-yr-old plantations. This number corresponded to the 90th percentile commonly used in other DRIS applications. Significantly different variances in both nutrient and dry-matter ratios between high and low basal diameter indicate that nutrient concentration as well as balance among nutrients influence basal-diameter growth. The DRIS technique appears promising for diagnosing the nutrient needs of this crop. View complete article To view this complete article, insert Disc 5 then click button8

Classification Model to Predict Fraser Fir Christmas Tree Grade

Abstract Objective measures of Christmas tree grade that would better quantify tree responses to cultural treatments were sought. Fraser fir Christmas tree attributes in a 3-year-old plantation were measured and correlated with conventional three-class grade categories, and a discriminate classification model was developed to test the predictability of grade based on tree attributes. Tree attributes best correlated with grade were basal diameter, terminal leader length and total bud and lateral bud frequencies on the terminal leader. Grade prediction based on five easily measured growth attributes produced a discriminate classification success rate of 72%. For. Sci. 36(1):45-53.

Nutrient Concentrations and Their Seasonal Patterns in Fraser Fir and Norway Spruce Grown in Seven Vegetation Management Programs

Fraser fir [Abies fraseri (Pursh) Poir.] and Norway spruce [Picea abies (L.) Karst.] were grown in seven vegetation management programs ranging from 100% cover of grass-dominated vegetation to bare soil on opposing north and south aspects. Concentrations of 13 nutrients were determined at three growth stages during 2 years: active terminal growth, cessation of terminal expansion, and dormancy. Aspect did not affect nutrient concentrations. Vegetation management programs bad a significant impact on nutrient concentration for both species. Nitrogen, Ca, B, Fe, and Mn concentrations during dormancy were negatively correlated with herbaceous biomass. In contrast, N during active growth and P and Mg concentrations during all stages were positively correlated with herbaceous biomass. Vegetation management only affected the seasonal trend of Mo. Seasonal trends varied by nutrient in both species.

Spruce Spider Mite Control with Safer’S Soap, Conventional Pesticides, and Combination Soap and Insecti-Cide Sprays on Fraser Fir in Centre Co., Pa, 1989

Abstract Nineteen treatments were evaluated to control spruce spider mite on heavily infested 5-6 ft Fraser fir Christmas trees. Each treatment was applied to 4 tree replicates. Foliar sprays were applied by using a 412 Solo Master mistblower. 303 ml of each treatment was applied to each replicate (100 gal/acre). Treatments were applied 2 Jun under cloudy skies. The air temperature was 82-88°F, 70% RH, and water pH was 5.0. Samples consisted of randomly removing 4 4-inch twigs from each replicate. Then they were placed in plastic bags and transported in an ice cooler back to the laboratory. Samples from each replicate were then passed through a mite brush, and the total number of viable spruce spider mite life stages (eggs, larvae, nymphs, adults) collected on a 5 inch circular sampling disc positioned directly beneath the brushes were counted with a stereo dissecting microscope. Posttreatment samples were collected 10 d (12 Jun) later.

Cloud chemistry measurements and estimates of acidic deposition on an above cloudbase coniferous forest

The wet, dry and cloud water deposition of acidic substances on the forest canopy are considered as major mechanisms for pollutant induced forest decline at high elevations. Direct cloud capture plays a predominant role of intercepting acidic substances in above cloud-base forests. We conducted a field study at Mt. Mitchell, North Carolina (35°44′05″N, 82°17′15″W; 2038 m MSL)—the highest peak in the eastern U.S.—during May–September 1986 and 1987 in order to analyze the chemistry of clouds in which the red spruce and Fraser fir stands stay immersed. It was found that Mt. Mitchell was exposed to cloud episodes 71% of summer days, the cloud immersion time being 28% for 1986 (a record drought summer in southeastern U.S.) and 41% for 1987. Sulfate, NO 3 − , NH 4 + and H + ions were found to be the major constituents of the cloud water, which was collected atop a 16.5 m tall meteorological tower situated among 6–7 m tall Fraser fir trees. The initiation of precipitation in clouds invariably diluted the cloud water acidity. The cloud water pH during short episodes (8 h duration or less), which resulted from the orographic lifting mechanisms, was substantially lower than that during long episodes, which were associated with meso-scale and synoptic-scale disturbances. Sulfate accounted for 65% acidity in cloud water, on the average, and contributed 2–3 times more than the NO 3 − . Inferential micrometeorological models were used to determine deposition of SO 4 2− and NO 3 − on the forest canopy and the hydrological input due to direct cloud capture mechanism. The cloud water deposition ranged between 32 and 55 cm a −1 in contrast to the bulk precipitation which was about 130 cm a −1 as measured by an on-site NADP (National Atmospheric Deposition Program) collector. For S compounds, wet, dry and cloud water deposition accounted for 19%, 11% and 70%, respectively for 1986, and 16%, 8% and 76%, respectively for 1987. For N compounds, dry deposition contributed 35% and 23% for 1986 and 1987, respectively, whereas, cloud water deposition contributed 50% and 65% for 1986 and 1987, respectively. Our estimates are compared with the reported literature values for the other sites.

Survey of diseases and insects of Fraser fir and red spruce in the southern Appalachian Mountains

AbstractDisease and insect surveys of three Southern Appalachian spruce‐fir ecosystems were conducted between 1985–1988. Visual tree decline was correlated with the presence of fungal pathogens and insect pests. Fungi were isolated from tree cankers, necrotic roots and diseased foliage; while insect incidence and impact was assessed visually. With the exception of damage to Fraser fir inflicted by the balsam wooly adelgid, little significant pathology or insect infestation was noted. This survey indicates that major diseases and insect damage, particularly on red spruce, appear not be primarily causal in the observed forest decline.

Role of air pollution in forest decline in Eastern North America

Evidence for and against three general mechanisms by which air pollution stress may cause or contribute to forest decline in eastern North America is examined. These mechanisms are (1) soil acidification, cation nutrient depletion, and subsequent Al toxicity, (2) direct and indirect effects of gaseous pollutants on the physiology and growth of forest trees; and (3) excess nitrogen deposition and subsequent soil acidification or physiological injury. Recent studies have revealed reductions in base saturation in some sites (both polluted and pristine), but the consequences of these changes to forest health and nutrition are not resolved. Aluminum toxicity may contribute to forest decline in red spruce (Picearubens L.) in high-elevation sites, but the data are contradictory. In forested landscapes in which regional decline (reduced tree growth and/or dieback) is reported, O3 is the only gaseous pollutant documented as a contributing factor in the eastern North America. Whereas this secondary pollutant exhibits a regional distribution and occurs at potentially phytotoxic levels, a linkage between O3 and forest decline is substantive only for loblolly pine (Pinustaeda Sarg.) in the southeast. Studies in high elevations do not support the hypothesis that O3 or hydrogen peroxide directly affects the growth of red spruce or fraser fir (Abiesfraseri Poir.).However, preliminary data link chronic-level O3 exposure with indirect effects, principally changes in drought tolerance in low-elevations (e.g., P. taeda) nd winter hardiness in high elevations (e.g., P. rubens).The emerging data on the role of air pollution as an environmental stress indicate that indirect effects (i.e., responses in which pollution alters the plant's ability to compete for limited resources or withstand other environmental stresses) are more important than direct effects (e.g., foliar necrotic lesions). Nitrogen saturation has been offered as an hypothesis for P. rubens decline, but no experimental data exist supporting this hypothesis.

Ice damage in spruce–fir forests of the Black Mountains, North Carolina

Spruce–fir ecosystem monitoring was initiated in 1985 in the southern Appalachians, United States, after reports of a red spruce (Picearubens Sarg.) decline in the northeast. Ice storms during the winter of 1986–1987 had a severe impact on spruce–fir forests in the Black Mountains of North Carolina, the location of Mount Mitchell, the highest peak in eastern North America. Mortality rates were higher for red spruce than for Fraser fir (Abiesfraseri (Pursh.) Poir.), 8.1 and 2.4%, respectively. Recent ice damage was apparent in 12.4% of surviving overstory stems, with red spruce having a 17% average decrease in height. Frequency of damage to stems tended to increase with increasing elevation. Little is known about the successional dynamics of southern high elevation montane second-growth forests. Our results suggest that ice storms may be an important cause of damage and mortality.

Influence of Growth Medium pH on the Growth of Container-grown Fraser Fir Seedlings

Abstract Seedlings of Fraser fir (Abies fraseri (Pursh) Poir.) were grown in sphagnum peat amended with 0 to 8 kg dolomitic limestone/m3 (0 to 13.5 lb/yd3). Initial pH ranged from 3.9 to 6.7. Best growth (21.2 cm (8.3 in) mean height at 19 months) was achieved with 1 and 2 kg/m3 (1.7 and 3.4 lb/yd3), with initial mean pH 4.2 and 4.5. Seedlings grown in media amended with 4 and 8 kg/m3 (6.7 and 13.5 lb/yd3) grew more slowly (17.4 (6.9 in) and 9.5 cm (3.7 in) in 19 months), and many were chlorotic, with poorly formed, blackened roots. At the conclusion of the first growth cycle (10 months), the slowest growth occurred in the most heavily limed peat (8 kg/m3 (13.5 lb/yd3), initial pH 6.8). Slower growth at 4 kg/m3 (6.7 lb/yd3, initial pH 5.0) became evident only after three growth cycles. Seedlings grew best within a fairly narrow range of pH (4.2 to 4.5), which is considerably more acidic than is generally recommended for conifers.

Spatial and Temporal Variability of Foliar Nutrient Levels in Fraser Fir Christmas Trees

Abstract The variation of Fraser fir (Abies fraseri [Pursh] Poir.) foliar nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) levels within plantations, the tree crown, and season of the year was studied. Extensive variation in nutrient concentrations existed. The data show that use of foliar nutrient levels for diagnosing nutrient sufficiency without regard to this variation could cause erroneous fertilization prescriptions. Recommended foliar sampling technique consists of sampling current-year's tissue from 2- or 3-yr-old south-facing branches in October. For. Sci 35(2): 632-639.

Biomass and Nutrient Accumulation in Fraser-fir Christmas Trees

Abstract Accumulation of biomass and nutrients was examined in a chronosequence of fraser-fir [Abies fraseri (Pursh) Poir.] Christmas trees. Estimated above-ground biomass of fraser-fir (2.4 to 2.7 m tall, 4444 trees/ha) after 7 years in the field was 40 t·ha-1, including foliage at 17 t·ha-1. At harvest, trees of this size removed 499 kg N, 33 kg P, 156 kg K, 160 kg Ca, and 26 kg Mg/ha. Foliage made up 46% and 42% of the total dry weight for 1.5- and 2.6-m trees, respectively. Forty-three percent to 63% of the above-ground nutrient content, depending on the element, was in foliage.

Plant Community Characteristics Associated with the Endangered Northern Flying Squirrel, Glaucomys sabrinus, in the Southern Appalachians

-Overstory and understory vegetation and physical parameters were sampled at sites where two endangered subspecies of the northern flying squirrel Glaucomys sabrinus are known to occur in the southern Appalachians. The 13 sites were disjunct, occurring at high elevations in mesic communities. Picea rubens was always present in the canopy (191173 trees/ha); the northernmost sites had greater densities of P. rubens and Betula lutea, while the southern sites had greater densities of Abies fraseri and Fagus grandifolia. Cluster analysis of overstory importance value data indicated the more southern sites and the more northern sites differed in species composition. In comparison the understory was highly variable among sites, both in species composition and percent cover and was therefore considered to be a poor indicator of suitable habitat for populations of G. sabrinus. Site characteristics indicate that the endangered populations of G. sabrinus may be restricted to patches of suitable habitat which remain at only a limited number of sites at high elevations in the southern Appalachian Mountains.

Nitrogen mineralization in high-elevation forests of the appalachians. II. Patterns with stand development in fir waves

Wave-like patterns of mortality and regeneration of balsam fir (Abies balsamea {L.} Mill.) and Fraser fir (A. fraseri {Pursh.} Poir.) forests at high elevations in the Appalachian Mountains offer a unique opportunity to study the effects of stand development on nitrogen cycling. We sampled two fir waves, one with Fraser fir on Mt. LeConte in the Great Smoky Mountains National Park, and one with balsam fir on Whiteface Mountain in New York. Net nitrogen mineralization for 3 summer months at Mt. LeConte was high in the dead fir zone (47 kg-N/ha), lower in the regeneration and juvenile zones (24 and 21 kg-N/ha), and highest in the mature zone (61 kg-N/ha). This sampling period probably accounted for about 60% of the annual total. The pattern was similar in the balsam fir wave on Whiteface Mountain, with N mineralization rates of 39 and 33 kg-N/ha over 2 months for the regenerating and juvenile zones, and 43 and 54 kg-N/ha for the mature and dead zones. Throughfall nitrogen followed a fairly similar pattern, with rates ranging from 4.5 to 10 kg-N/ha for 2 or 3 months across all zones at both sites. Tension-free lysimeters indicated very little leaching of nitrogen below 30 cm depth (the maximum was 2.6 kg-N/ha), but these estimates may be low. We conclude that nitrogen mineralization is high at all stages of stand development, perhaps exceeding the uptake capacity of the trees. Rates of nitrogen leaching may be high in these ecosystems and should receive further attention.

Structure and function of flexure wood in Abies fraseri.

Wood produced during flexure in one-year-old leaders of Abies fraseri (Pursh) Poir. (Fraser fir) was analyzed anatomically and radio-densitometrically. More xylem cells were produced in stems subjected to flexing than in stems that were not flexed. The lumens of tracheids produced in response to flexure were smaller than the lumens of tracheids in normal wood. This was manifest as an increase in the cell wall area/cell lumen area ratio. Microfibril orientation in flexure-induced wood approached the less extreme values found in compression wood. The growth ring composed of flexure-induced wood also had a greater density than normal wood. Compression wood, as defined by cellular characteristics observed in transverse section, was absent in flexed stems. Detailed analysis of the anatomical structure, wood density and biomechanical properties of flexure-induced wood indicated that it has more in common with compression wood than with normal wood.

Nitrogen mineralization in high elevation forests of the Appalachians. I. Regional patterns in southern spruce-fir forests

Annual and seasonal rates of net nitrogen mineralization were determined for 19 sites in the spruce-fir forests of the Southern Appalachian Mountains. These sites included high and low elevation stands of red spruce (Picea rubens Sarg.) and Fraser fir (Abies fraseri (Pursh.) Poir.) on east and west exposures on Whitetop Mountain, Virginia; Mt. Mitchell, North Carolina; and Clingman's Dome in the Great Smoky Mountains National Park. Mineralization rates were determined using in situ soil incubations in PVC tubes with ion exchange resin bags placed in the bottom of the tubes to collect leachate. Throughfall was collected in resin bags placed in the top of the tubes. Average initial NH4-N + NO3-N ranged from 0.6 to 4.8 kg N/ha across all plots, and average mineralization rates ranged from 26 to 180 kg-N ha−1 yr−1. Throughfall ranged from 18 to 32 kg-N ha−1 yr−1 with NH4-N accounting for about two-thirds of the throughfall N across all sites. Throughfall and mineralization rates were not related to elevation or exposure. The high rates of N mineralization and relatively high nitrate concentrations indicate that leaching losses of nitrogen and associated cations could be substantial.

Effects of Frequency of Chemical Weed Control on Growth and Quality of Christmas Trees1

Abstract Effective weed control is essential to the production of high-quality Christmas trees on most planting sites. Many growers use herbicides applied along rows of trees, in combination with mowing between rows, to control competing grasses and broadleaved weeds. This study evaluated one-time, biannual, and annual applications of herbicide during a 6-year period on growth and quality of different Christmas tree species planted on moderately dry and moist planting sites. Increased height growth from more frequent applications was limited primarily to the drier site, and even on that site rotation length would have been reduced by only 1 year. Christmas tree quality, as reflected by foliage density and tree weights, generally improved on both areas as herbicides were applied more frequently. Colorado spruce, Douglas-fir, and Fraser fir benefited more than Scotch and white pines. North. J. Appl. For. 6:15-17, March 1989.

A DRIS application to Fraser Fir Christmas Trees

Abstract A study developing a DRIS application to evaluate foliar nitrogen (N), phosphorus (P.), potassium (K), calcium (Ca), and magnesium (Mg) nutrition, was conducted on a 3‐year‐old Fraser fir [Abies fraseri(Pursh) Poir.] Christmas tree plantation in Watauga county, North Carolina. Preliminary DRIS norms and index equations were developed from premium grade Christmas trees for the five nutrients analyzed. In contrast to most crops where growth or yield are assessed. Fraser fir Christmas tree performance was evaluated by conventional grading procedures based on tree quality. Preliminary evaluation of DRIS performance on the 79‐tree data set suggested that assessments of nutritional balance as well as an examination of individual nutrient concentrations are needed to diagnose the nutrient status of Fraser Fir Christmas trees

Foliar elemental composition of spruce-fir in the southern blue ridge province

Data are presented for what we believe to be the first assessment of the elemental foliar status of red spruce (Picea rubens Sarg.) and Fraser fir [Abies fraseri (Pursh.) Poir.] trees in the high elevation forests of the southern Appalachian mountans.

Spruce Spider Mite Control on Fraser Fir, State College, 1987

Abstract Fraser fir (1-2 m high) growing at a Christmas tree plantation in State College, Pa., were used to evaluate acaricides against spruce spider mites. Treatments were assigned to heavily infested trees at random and consisted of 4 single-tree replicates. Pretreatment counts indicated 182 mites/single-tree sample. Treatments were applied with a KWH backpack mistblower operating at half throttle on setting 3 for 40 s, delivering 910 ml of finished spray/tree. The first application was made to all trees 21 May under cloudy skies, 18°C, and 8-16 km/h breeze. A second spray was applied to some of the trees 2 Jun under partly sunny skies, 27°C, and 0-16 km/h breeze. Treatments were evaluated 1, 2, 4, and 8 wk after the second application by removing four 10-15-cm-long lateral branch tips from each of the 4 replicates/treatment. Samples were transported in coolers or insulated boxes and shipped by overnite carrier. All samples were immediately processed by passing them through a mite brush 6 times to dislodge mites to a rotating glass plate coated with Tween 20. The number of live mites was counted with the aid of a dissecting microscope.

Spruce Spider Mite Control with Insecticidal Soap and Conventional Pesticides on Fraser Fir in Centre County, 1987

Abstract Eighteen treatments were evaluated to control spruce spider mites on heavily infested 5-6-ft Fraser fir Christmas trees. Each treatment was applied to 4-tree replicates. Foliar sprays were applied by using a CO2 sprayer with one 8004VS Teejet nozzle operating at 28 psi and mounted on the end of a 24-inch boom. 940 ml of each treatment was applied to each replicate. Treatments were applied 13 May under clear, sunny skies. The air temperature was 85°F and 70% RH. Samples consisted of randomly removing four 4-inch twigs from each replicate. The twigs were placed in plastic bags and transported in an ice cooler to the laboratory. Samples from each replicate were then passed through a mite brush, and the number of viable spruce spider mite life stages (larvae, nymphs, adults) collected on a 5-inch sampling disk positioned directly beneath the brushes was counted with a stereo dissecting microscope. Posttreatment samples were collected 29 May and 11 Jun.