Acid Black Cherry Erect Download
Edelira Longinotti
J. ashei and J. pinchotii were analyzed for areas of speciation and possible hybridization. Theirinteractions with each other and with J. virginiana, J. scopulorum, J. monosperma, J. deppeana, and J.flaccida were examined, using both morphological and terpenoid characters.
Reports results of a comparative study of the development of male and female cones in J.seravschanica, J. semiglobosa, J. turkestanica, J. turcomanica, J. communis, and J. virginiana atTashkent. Considerable differences were observed between species in the time of initiation anddifferentiation of cones.
In order to determine the suitability of finely ground woods and barks of Libocedrus decurrens,Taxodium distichum, Sequoia sempervirens, Larix occidentalis, Tsuga canadensis, Abies magnifica, A.concolor, Pseudotsuga taxifolia, Juniperus virginiana, and Picea engelmannii as mulches and soilamendments, their rates of decomposition in soil were determined in the laboratory at two levels of N bymeasuring CO2 evolution for 53-800 days. The woods and barks of all these species were considerablymore resistant to biological attack than was shortleaf pine sawdust. L. decurrens, T. distichum, S.sempervirens, T. canadensis, and J. virginiana were particularly resistant to decomposition. Owing tothe slow rates of decomposition, the soil was able to furnish adequate available N for maximum rates ofdecomposition in all cases, and supplementary N was not needed.
Describes the work of MITOSIS (Montana Interagency Tree or Shrub Improvement Study), a programset up by three agencies (USDA Forest Service, USDA Soil Conservation Service, and the ForestryDivision of the Montana Department of Natural Resources and Conservation) to develop improvedvarieties of trees or shrubs for conservation purposes. Projects include: collection and progeny testingof seed from superior trees and shrubs in shelterbelts; improving the establishment of conifers;standardization of woody plant certification; and evaluation of Rocky Mountain juniper (Juniperusscopulorum) and eastern redcedar (J. virginiana) strains in the Great Plains.
8. Baer, N.W. 1985. Nutrient content in eastern redcedar foliage: seasonal variation. Tech.Bull. 86. Brookings, SD: South Dakota State University, Agriculture Experiment Station. 9 p.
Eastern redcedar seedlings grown at daytime temperatures of 90o F responded differently in top androot growth to four combinations of night temperature and photoperiod. Greatest growth and highesttop/root ratios were obtained by a diurnal fluctuation from 90 to 59o F with a 20-hour photoperiod (long-moderate). A diurnal fluctuation from 90 to 45o F with a 20-hour photoperiod (long-cold) produced thesmallest seedlings with the lowest top/root ratios. Heights and weights at 59o F (moderate) nighttemperature were significantly greater under 20-hour (long) photoperiod than under 14-hour (normal)photoperiod. Variation in growth response within treatment was greatest under the 90 to 45o F (long-cold) and least under the 90 to 80o F (long-hot) temperature regime. Seedling heights and top/rootratios tended to equalize after 6 months in an outdoor environment, but significant differences in totalweight did not change.
Photosynthesis, leaf conductance, water potential, and tissue water relations were examined for 2-to 6-m-tall saplings of species from habitats of varying soil moisture content in the growing seasons of1980 (hot and dry) and 1981 (wet). Drought substantially reduced leaf conductance in all angiospermtrees (Quercus velutina, Q. alba, Q. rubra, Cornus florida, and Acer saccharum), but only slightlyreduced conductance of Juniperus virginiana. C. florida showed the most pronounced response todrought, because of its inability to avoid low water potential; this is attributable to its known habit ofshallow rooting. Differences in drought adaptation were apparent among the broadleaves, withQuercus spp. (adapted to drier sites) showing generally lower osmotic potentials at full turgor andturgor loss point, higher moduli of leaf tissue elasticity, and higher rates of photosynthesis duringdrought, compared with A. saccharum and C. florida. J. virginiana, usually found on very dry sites,showed a different pattern of drought adaptation: an inherently low capacity for water loss, and theability to sustain stomatal opening at low water potentials.
Many of the trends in anatomical variation in different parts of the tree in J. virginiana resembledthose observed in Thuja occidentalis. Similar tendencies were noted in such characters as size of thetracheids, size and distribution of the intertracheary pits, size and number of pits per crossing field,height and distribution of rays, and size of ray cells. Other features usually regarded as valuable forpurposes of identification such as the thickness and character of the walls of the ray and xylemparenchyma cells also varied considerably. Because of such variability, it is clear that the selection ofcharacters that will ultimately prove diagnostic must be held in abeyance until there is more completeknowledge of the range of variation in related forms. An expansion of certain of the rays to amultiseriate condition, such as observed in Thuja occidentalis, was also noted in all three localspecies of Juniperus. All adventitious roots arising from stems or branches connected with rays in thexylem were nearly always of this unusual type.
Seeds of J. virginiana possess dormant embryos that require a period of 3 months at 5o C to after-ripen; 1o C is less effective and 10o C is totally ineffective. A large percent of seeds haveimpermeable coats, which may be made permeable by exposure to moisture at a temperature of 25oC for 2-8 weeks or by soaking for 30 minutes in concentrated H2SO4. Such treatment should precedestratification.
A comparative study was made of the lignification of the walls of ray parenchyma cells andmembranes of bordered pits in specimens of Pinus sylvestris, P. strobus, Larix decidua, andJuniperus virginiana using light microscopy, histochemical tests, micro-autoradiography, and UVmicrospectrophotometry. It was shown that lignification in ray parenchyma cell walls of pines of thesubgenus Haploxylon may occur during heartwood formation. In other species investigated,lignification of these cells occurred at the cambial zone. Incrustation of pit membranes by polyphenolsalso occurs during heartwood formation.
A series of tests on the water conductivity and measurements of the tracheids of stems ofJuniperus horizontalis and J. virginiana yielded the following facts: (1) No significant difference existsbetween the specific conductivity of these two species when taken from approximately the samehabitat. Therefore, the creeping habit of J. horizontalis apparently has no direct relation to the specificwater-conductivity of its stem. (2) The values for specific water-conductivity of both species aredefinitely low, and accordingly the dimensions of the tracheids and their lumen areas as seen intransverse view are also small. The deviations are negligibly small and compensatingly distributed. (3) The growth rate, as determined from transverse sections, varies in the two species. In seasons ofsevere drought it is apparently quite similar in both species, while under more favorable conditions J.virginiana grows much faster.
Concentrations of chlorophyll a and b were determined in 1g of leaf material taken from a maturetree at weekly intervals over the period November 1967 to October 1969. A multiple regressionanalysis was made to determine the relations between chlorophyll concentrations and temperature,precipitation, cloud cover, and dry weight, and the results are briefly discussed.
Significant positive correlations were found between the concentrations of chlorophyll a andchlorophyll b, and between chlorophyll and dry weight; and negative regressions of chlorophyll ontemperature and on total radiation. Seasonal differences are discussed.
Investigations on leaves of Abies concolor, Juniperus virginiana, Picea pungens, Pinus banksiana,P. laricio, P. strobus, P. sylvestris, and Thuja orientalis showed that photosynthetic cells decreased insize and increased in frequency from the basal to the apical parts. The stomatal frequency increasedin the same direction. This bears out the observations made by Zalenski and others on plants ingeneral.
Growth rings from Juniperus virginiana were examined from 10 trees at each of three sitesdistributed along an ecotonal transect in west-central Oklahoma. Tree rings were examined todetermine the utility of eastern redcedar as a source of surrogate climatic data. False rings werecommon, and some were correlative amongst the three study sites. In spite of a westward-increasingtendency of partial false rings, the combination of correlative true annual rings, correlative false rings,and fire scars provided some useful data for identifying the presence of past droughts on the GreatPlains.
The factors responsible for delayed germination of eastern redcedar (Juniperus virginiana) seedare the waxy coat and a resting condition of the embryo. The waxy coat can be removed by soakingseeds for several hours in alcohol, or by pouring warm water over the seeds and bringing it to the boil,repeating the operation twice. In order to overcome the resting condition of the embryo, seed shouldbe stratified from about the middle of December to the middle of March, and then sown in well-prepared seedbeds of sandy soil.
The seasonal trends in the calcium content of the foliage of Fagus grandifolia, Magnoliaacuminata, Populus tremuloides, Juniperus virginiana, and Pinus strobus, were studied. In all casesthe calcium content, expressed either on a percentage or on an absolute-amount basis, was found toincrease progressively throughout the growing season. The calcium content of the foliage ofevergreen trees increased throughout the growing season but remained fairly constant during thewinter months. The longer the foliage of a single species remained on the tree, the higher was itscalcium content. The calcium content of mature foliage of 27 forest trees was determined and theywere grouped accordingly: (1) Species averaging more than 2.0 percent of calcium in their foliage -tulip poplar, redcedar, basswood, black locust, mockernut hickory, bitternut hickory, white cedar,hophornbeam, trembling aspen, white ash, and black cherry. (2) Species whose foliage containedfrom 1.0 to 2.0 percent of calcium - shagbark hickory, American elm, sugar maple, Norway spruce,white oak, red oak, yellow birch, chestnut oak, white pine, and balsam fir. (3) Species whose foliagecontained less than 1.0 percent of calcium - red maple, red pine, hemlock, beech, scotch pine, andred spruce.
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