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We studied the effects of long-term exposure (nine years) of birch (Betula papyrifera) trees to elevated CO2 and/or O3 on reproduction and seedling development at the Aspen FACE (Free-Air Carbon Dioxide Enrichment) site in Rhinelander, WI. We found that elevated CO2 increased both the number of…
Author(s): Joseph N.T. Darbah, Mark E. Kubiske, Neil Nelson, Elina Oksanan, Elina Vapaavuori, David F. Karnosky
Keywords: seeds, seed quality, seed germination, flower production, seedlings growth and survival, elevated tropospheric ozone and carbon dioxide
Source: Environmental Pollution. 155: 446-452.
Year: 2008
1. Pinus tuedli seeds, developed under ambient or elevated (ambient + 200 Ч1-1) [CO2], were collected from Duke Forest, North Carolina, USA in October 1998. Seeds were germinated in nutrient-deficient soil in either ambient or elevated [COJ (ambient + 200 Ч1-1) greenhouse chambers and allowed to…
Author(s): M. Hussain, M. E. Kubiske, K. F. Connor
Keywords: Elevated CO2, Pinus taeda, seed germination, seed lipids, seed production
Source: Functional Ecology 15, 344-350
Year: 2001
Variation in speed of seed germination was investigated among ponderosa pine trees representing 225 locations in central Oregon. Results suggested that at least some of the geographic variation is related to the severity of summer drought. In general, germination speed was greater in locations with…
Author(s): John C. Weber, Frank C. Sorensen
Keywords: Geographic variation, seed germination, ponderosa pine, adaptation, drought, central Oregon
Source: Res. Pap. PNW-RP-444. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 12 p
Year: 1992
Hundred-seed weights from 15 trees in each stand averaged 330 mg; 100-seed weights differed significantly among trees within stands and among stands. Germination of filled seed averaged 95 percent; germination differed significantly among trees within stands, but not among stands. Detailed seed…
Author(s): Richard M. Jeffers
Keywords: Pinus banksiana, seed weight, seed germination, varation, seed quality
Source: Research Note NC-328. St. Paul, MN: U.S. Dept. of Agriculture, Forest Service, North Central Forest Experiment Station
Year: 1985
The 38 papers in this proceedings are divided into six sections; the first includes an overview paper and documentation of the first Shrub Research Consortium Distinguished Service Award. The next four sections cluster papers on restoration and revegetation, soil and microsite requirements,…
Author(s): Ann L. Hild, Nancy L. Shaw, Susan E. Meyer, D. Terrance Booth, E. Durant McArthur
Keywords: wildland shrubs, seed, soil, restoration, rehabilitation, seed bank, seed germination, biological soil crusts
Source: Proc. RMRS-P-31. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 216 p.
Year: 2004
Longleaf pine, although widely distributed in the presettlement forests of the southern Coastal Plain, now occupies less than 10 percent of its original range. It is a highly desirable species because it resists fire, insects, and disease and produces excellent quality solid-wood products.…
Author(s): James P. Barnett, John M. McGilvray
Keywords: Nursery practices, Pinus palustris Mill, planting techniques, seed germination
Source: Gen. Tech. Rep. SRS-14. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 36 p.
Year: 1997
Tree improvement programs have influenced significantly the quality of southern pine seeds produced when compared to collections from native stands. Seed orchard management practices such as fertilization can increase seed size and reduce seed dormancy. These result in the need for less complex…
Author(s): James P. Barnett
Keywords: Pinus spp, seed germination, seed dormancy, seed storage, cone maturity
Source: The Forestry Chronicle, Vol. 72, NO. 5
Year: 1996
Rangeland seedings of spiny hopsage (Gruyia spinosa [Hook.] Moq.) may be made with either bracted utricles or seeds. Problems have resulted from inconsistent use of terminology describing these 2 structures and the fact their germination and seedling emergence is not the same with similar…
Author(s): Nancy L. Shaw, Emerenciana G. Hurd, Marshall R. Haferkamp
Keywords: chenopod, diaspore, Grayia spinosa, seed germination, utricle
Source: Journal of range management. 49(6): 551-553
Year: 1996
Germination and early growth on rotten wood and duff under several shade levels were observed for Douglas-fir, Sitka spruce, western hemlock, western redcedar, lodgepole pine, Pacific silver fir, and red alder. Nutrients were more abundant in duff than in rotten wood. Seedlings usually were larger…
Author(s): Don Minore
Keywords: seed germination, growth factors
Source: Res. Pap. PNW-RP-135. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 21 p
Year: 1972
Lomatium dissectum (Apiaceae) is a perennial, herbaceous plant of wide distribution in Western North America. At the time of dispersal, L. dissectum seeds are dormant and have under-developed embryos. The aims of this work were to determine the requirements for dormancy break and germination, to…
Author(s): Melissa Scholten, Jacklyn Donahue, Nancy L. Shaw, Marcelo D. Serpe
Keywords: Apiaceae, cold stratification, Lomatium dissectum, morphophysiological dormancy, secondary dormancy, seed germination
Source: Annals of Botany 103: 1091-1101.
Year: 2009