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John Cardina - One of the best experts on this subject based on the ideXlab platform.
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Environmental factors affecting seed persistence of annual Weeds across the U.S. corn belt
Weed Science, 2005Co-Authors: Adam S. Davis, John Cardina, Karen A. Renner, Frank Forcella, Gregg A. Johnson, George O. Kegode, John L. Lindquist, Edward C. Luschei, Christy L. Sprague, Martin M. WilliamsAbstract:Abstract Weed Seedbanks have been studied intensively at local scales, but to date, there have been no regional-scale studies of Weed seedbank persistence. Empirical and modeling studies indicate that reducing Weed seedbank persistence can play an important role in integrated Weed management. Annual seedbank persistence of 13 summer annual Weed species was studied from 2001 through 2003 at eight locations in the north central United States and one location in the northwestern United States. Effects of seed depth placement, tillage, and abiotic environmental factors on seedbank persistence were examined through regression and multivariate ordinations. All species examined showed a negative relationship between hydrothermal time and seedbank persistence. Seedbank persistence was very similar between the two years of the study for common lambsquarters, giant foxtail, and velvetleaf when data were pooled over location, depth, and tillage. Seedbank persistence of common lambsquarters, giant foxtail, and velvet...
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crop rotation and tillage system effects on Weed Seedbanks
Weed Science, 2002Co-Authors: John Cardina, Catherine P. Herms, Douglas J DoohanAbstract:Abstract We characterized the size and species composition of the Weed seedbank after 35 yr of continuous crop rotation and tillage system treatments at two locations in Ohio. Spring Seedbanks were monitored during 1997, 1998, and 1999 in continuous corn (CCC), corn–soybean (CS), and corn–oats–hay (COH) rotations in moldboard plow (MP), chisel plow (CP), and no-tillage (NT) plots where the same herbicide was used for a given crop each growing season. There were 47 species at Wooster and 45 species at Hoytville, with 37 species occurring at both locations in all 3 yr. Crop rotation was a more important determinant of seed density than was tillage system. Seed density was highest in NT and generally declined as tillage intensity increased. Seeds accumulated near the surface (0 to 5 cm) in NT but were uniformly distributed with depth in other tillage systems. At both locations there was a significant interaction between tillage and rotation for estimates of the total seed density. Seed density was highest in...
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Weed Seedbanks of the U.S. Corn Belt: Magnitude, Variation, Emergence, and Application
Weed Science, 1992Co-Authors: Frank Forcella, Karen A. Renner, Robert G. Wilson, Jack Dekker, Robert G. Harvey, David A. Alm, Douglas D. Buhler, John CardinaAbstract:Seedbanks and seedling emergence of annual Weeds were examined in arable fields at eight locations in the Corn Belt. Seed densities were estimated by direct seed extraction from each of several soil cores in each sampled plot. Average total seedbank densities ranged from 600 to 162 000 viable seed m2 among locations. Coefficients of variation (CV) typically exceeded 50%. CV for seed densities of individual species usually exceeded 100%, indicating strongly aggregated distributions. CV were lower for species with dense seed populations than those with sparse seed populations. Variance of total seedbank densities was unstable when < 10 cores were examined per plot, but stabilized at all locations when 2 15 cores were analyzed, despite a 12-fold difference in plot size and 270-fold difference in seed density among locations. Percentage viable seed that emerged as seedlings in field plots ranged from < 1% for yellow rocket to 30% for giant foxtail. Redroot pigWeed and common lambsquarters were the most frequently encountered species. Emergence percentages of these species were related inversely to rainfall or air temperatures in April or May, presumably because anoxia and/or high temperatures induced secondary dormancy in nondormant seed. From 50 to 90% of total seed in the seedbank were dead. This information can be employed by bioeconomic Weed management models, which currently use coarse estimates of emergence percentages to customize recommendations for Weed control. Nomenclature: Common lambsquarters, Chenopodium album L. #3 CHEAL; giant foxtail, Setaria faberi Herrm. # SETFA; redroot pigWeed, Amaranthus retroflexus L. # AMARE; yellow rocket, Barbarea vulgaris R. Br. # BARVU. 'Received for publication May 23, 1992, and in revised form August 24, 1992. Joint contribution of the U.S. Dep. Agric., Agric. Res. Serv.; Univ. of Illinois; Iowa St. Univ.; Michigan St. Univ.; Univ. of Minnesota; Univ. of Nebraska; Ohio St. Univ.; and Univ. of Wisconsin. Minn. Sci. J. Series No. 19,973. 2Res. Agronomist, USDA-ARS, Morris MN 56267; Professor, Univ. of Nebraska Panhandle Res. & Ext. Cen., Scottsbluff, NE; Assoc. Professor, Michigan St. Univ., E. Lansing, MI; Assoc. Professor, Dep. of Agronomy, Iowa State Univ., Ames, IA; Professor, Dep. of Agronomy, Univ. of Wisconsin, Madison, WI; Res. Agronomist, USDA-ARS, Urbana, IL; Res. Agronomist, USDA-ARS, St. Paul, MN; and Res. Scientist, Dep. of Agronomy, Ohio State Univ., Wooster, OH. 3Letters following this symbol are a WSSA-approved computer code from Composite List of Weeds, Revised 1989. Available from WSSA, 309 West Clark Street, Champaign, IL 61820. 4P. Westra, Colorado State Univ. Unpublished data. 5NC-202 is the official designation for a regional committee composed of the following U.S. states and Canadian province: Colorado, Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, Ontario, South Dakota, and Wisconsin. The committee's assignment is to develop a regional bioeconomic Weed management model for corn and soybean. Additional index words: Buried seed, seedling emergence, soil seed reserve, bioeconomic Weed management models.
Cardina John - One of the best experts on this subject based on the ideXlab platform.
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Environmental factors affecting seed persistence of annual Weeds across the U.S. corn belt
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Davis, Adam S, Forcella Frank, Renner, Karen A., Cardina John, Johnson, Gregg A., Kegode George, Lindquist, John L., Luschei, Edward C, Sprague, Christy L, Williams, Martin M.Abstract:Weed Seedbanks have been studied intensively at local scales, but to date, there have been no regional-scale studies of Weed seedbank persistence. Empirical and modeling studies indicate that reducing Weed seedbank persistence can play an important role in integrated Weed management. Annual seedbank persistence of 13 summer annual Weed species was studied from 2001 through 2003 at eight locations in the north central United States and one location in the northwestern United States. Effects of seed depth placement, tillage, and abiotic environmental factors on seedbank persistence were examined through regression and multivariate ordinations. All species examined showed a negative relationship between hydrothermal time and seedbank persistence. Seedbank persistence was very similar between the two years of the study for common lambsquarters, giant foxtail, and velvetleaf when data were pooled over location, depth, and tillage. Seedbank persistence of common lambsquarters, giant foxtail, and velvetleaf from October 2001 through 2002 and October 2002 through 2003 was, respectively, 52.3% and 60.0%, 21.3% and 21.8%, and 57.5% and 57.2%. These results demonstrate that robust estimates of seedbank persistence are possible when many observations are averaged over numerous locations. Future studies are needed to develop methods of reducing seedbank persistence, especially for Weed species with particularly long-lived seeds
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Weed Seed Bank Emergence across the Corn Belt
Iowa State University Digital Repository, 1997Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Harvey, Robert G., Cardina John, Kremer, Robert J., Anderson, Randy L., Alm David, Clay Sharon, Buhler, Douglas D.Abstract:Field experiments, conducted from 1991 to 1994, generated information on Weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of Weed Seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartWeed, 25.1 (65); common purslane, 15.4 (135); common ragWeed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigWeed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotWeed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June
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Weed Seedbanks of the U.S. Corn Belt: Magnitude, Variation, Emergence, and Application
Iowa State University Digital Repository, 1992Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Dekker, Jack H., Harvey, Robert G., Alm, David A., Buhler, Douglas D., Cardina JohnAbstract:Seedbanks and seedling emergence of annual Weeds were examined in arable fields at eight locations in the Corn Belt. Seed densities were estimated by direct seed extraction from each of several soil cores in each sampled plot. Average total seedbank densities ranged from 600 to 162 000 viable seed m⁻² among locations. Coefficients of variation (CV) typically exceeded 50%. CV for seed densities of individual species usually exceeded 100%, indicating strongly aggregated distributions. CV were lower for species with dense seed populations than those with sparse seed populations. Variance of total seedbank densities was unstable when \u3c 10 cores were examined per plot, but stabilized at all locations when ≥ 15 cores were analyzed, despite a 12-fold difference in plot size and 270-fold difference in seed density among locations. Percentage viable seed that emerged as seedlings in field plots ranged from \u3c 1% for yellow rocket to 30% for giant foxtail. Redroot pigWeed and common lambsquarters were the most frequently encountered species. Emergence percentages of these species were related inversely to rainfall or air temperatures in April or May, presumably because anoxia and/or high temperatures induced secondary dormancy in nondormant seed. From 50 to 90% of total seed in the seedbank were dead. This information can be employed by bioeconomic Weed management models, which currently use coarse estimates of emergence percentages to customize recommendations for Weed control
Forcella Frank - One of the best experts on this subject based on the ideXlab platform.
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Environmental factors affecting seed persistence of annual Weeds across the U.S. corn belt
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Davis, Adam S, Forcella Frank, Renner, Karen A., Cardina John, Johnson, Gregg A., Kegode George, Lindquist, John L., Luschei, Edward C, Sprague, Christy L, Williams, Martin M.Abstract:Weed Seedbanks have been studied intensively at local scales, but to date, there have been no regional-scale studies of Weed seedbank persistence. Empirical and modeling studies indicate that reducing Weed seedbank persistence can play an important role in integrated Weed management. Annual seedbank persistence of 13 summer annual Weed species was studied from 2001 through 2003 at eight locations in the north central United States and one location in the northwestern United States. Effects of seed depth placement, tillage, and abiotic environmental factors on seedbank persistence were examined through regression and multivariate ordinations. All species examined showed a negative relationship between hydrothermal time and seedbank persistence. Seedbank persistence was very similar between the two years of the study for common lambsquarters, giant foxtail, and velvetleaf when data were pooled over location, depth, and tillage. Seedbank persistence of common lambsquarters, giant foxtail, and velvetleaf from October 2001 through 2002 and October 2002 through 2003 was, respectively, 52.3% and 60.0%, 21.3% and 21.8%, and 57.5% and 57.2%. These results demonstrate that robust estimates of seedbank persistence are possible when many observations are averaged over numerous locations. Future studies are needed to develop methods of reducing seedbank persistence, especially for Weed species with particularly long-lived seeds
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Weed Seed Bank Emergence across the Corn Belt
Iowa State University Digital Repository, 1997Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Harvey, Robert G., Cardina John, Kremer, Robert J., Anderson, Randy L., Alm David, Clay Sharon, Buhler, Douglas D.Abstract:Field experiments, conducted from 1991 to 1994, generated information on Weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of Weed Seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartWeed, 25.1 (65); common purslane, 15.4 (135); common ragWeed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigWeed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotWeed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June
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Weed Seedbanks of the U.S. Corn Belt: Magnitude, Variation, Emergence, and Application
Iowa State University Digital Repository, 1992Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Dekker, Jack H., Harvey, Robert G., Alm, David A., Buhler, Douglas D., Cardina JohnAbstract:Seedbanks and seedling emergence of annual Weeds were examined in arable fields at eight locations in the Corn Belt. Seed densities were estimated by direct seed extraction from each of several soil cores in each sampled plot. Average total seedbank densities ranged from 600 to 162 000 viable seed m⁻² among locations. Coefficients of variation (CV) typically exceeded 50%. CV for seed densities of individual species usually exceeded 100%, indicating strongly aggregated distributions. CV were lower for species with dense seed populations than those with sparse seed populations. Variance of total seedbank densities was unstable when \u3c 10 cores were examined per plot, but stabilized at all locations when ≥ 15 cores were analyzed, despite a 12-fold difference in plot size and 270-fold difference in seed density among locations. Percentage viable seed that emerged as seedlings in field plots ranged from \u3c 1% for yellow rocket to 30% for giant foxtail. Redroot pigWeed and common lambsquarters were the most frequently encountered species. Emergence percentages of these species were related inversely to rainfall or air temperatures in April or May, presumably because anoxia and/or high temperatures induced secondary dormancy in nondormant seed. From 50 to 90% of total seed in the seedbank were dead. This information can be employed by bioeconomic Weed management models, which currently use coarse estimates of emergence percentages to customize recommendations for Weed control
Buhler, Douglas D. - One of the best experts on this subject based on the ideXlab platform.
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Weed Seed Bank Emergence across the Corn Belt
Iowa State University Digital Repository, 1997Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Harvey, Robert G., Cardina John, Kremer, Robert J., Anderson, Randy L., Alm David, Clay Sharon, Buhler, Douglas D.Abstract:Field experiments, conducted from 1991 to 1994, generated information on Weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of Weed Seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartWeed, 25.1 (65); common purslane, 15.4 (135); common ragWeed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigWeed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotWeed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June
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Weed Seedbanks of the U.S. Corn Belt: Magnitude, Variation, Emergence, and Application
Iowa State University Digital Repository, 1992Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Dekker, Jack H., Harvey, Robert G., Alm, David A., Buhler, Douglas D., Cardina JohnAbstract:Seedbanks and seedling emergence of annual Weeds were examined in arable fields at eight locations in the Corn Belt. Seed densities were estimated by direct seed extraction from each of several soil cores in each sampled plot. Average total seedbank densities ranged from 600 to 162 000 viable seed m⁻² among locations. Coefficients of variation (CV) typically exceeded 50%. CV for seed densities of individual species usually exceeded 100%, indicating strongly aggregated distributions. CV were lower for species with dense seed populations than those with sparse seed populations. Variance of total seedbank densities was unstable when \u3c 10 cores were examined per plot, but stabilized at all locations when ≥ 15 cores were analyzed, despite a 12-fold difference in plot size and 270-fold difference in seed density among locations. Percentage viable seed that emerged as seedlings in field plots ranged from \u3c 1% for yellow rocket to 30% for giant foxtail. Redroot pigWeed and common lambsquarters were the most frequently encountered species. Emergence percentages of these species were related inversely to rainfall or air temperatures in April or May, presumably because anoxia and/or high temperatures induced secondary dormancy in nondormant seed. From 50 to 90% of total seed in the seedbank were dead. This information can be employed by bioeconomic Weed management models, which currently use coarse estimates of emergence percentages to customize recommendations for Weed control
Renner, Karen A. - One of the best experts on this subject based on the ideXlab platform.
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Environmental factors affecting seed persistence of annual Weeds across the U.S. corn belt
DigitalCommons@University of Nebraska - Lincoln, 2005Co-Authors: Davis, Adam S, Forcella Frank, Renner, Karen A., Cardina John, Johnson, Gregg A., Kegode George, Lindquist, John L., Luschei, Edward C, Sprague, Christy L, Williams, Martin M.Abstract:Weed Seedbanks have been studied intensively at local scales, but to date, there have been no regional-scale studies of Weed seedbank persistence. Empirical and modeling studies indicate that reducing Weed seedbank persistence can play an important role in integrated Weed management. Annual seedbank persistence of 13 summer annual Weed species was studied from 2001 through 2003 at eight locations in the north central United States and one location in the northwestern United States. Effects of seed depth placement, tillage, and abiotic environmental factors on seedbank persistence were examined through regression and multivariate ordinations. All species examined showed a negative relationship between hydrothermal time and seedbank persistence. Seedbank persistence was very similar between the two years of the study for common lambsquarters, giant foxtail, and velvetleaf when data were pooled over location, depth, and tillage. Seedbank persistence of common lambsquarters, giant foxtail, and velvetleaf from October 2001 through 2002 and October 2002 through 2003 was, respectively, 52.3% and 60.0%, 21.3% and 21.8%, and 57.5% and 57.2%. These results demonstrate that robust estimates of seedbank persistence are possible when many observations are averaged over numerous locations. Future studies are needed to develop methods of reducing seedbank persistence, especially for Weed species with particularly long-lived seeds
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Weed Seed Bank Emergence across the Corn Belt
Iowa State University Digital Repository, 1997Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Harvey, Robert G., Cardina John, Kremer, Robert J., Anderson, Randy L., Alm David, Clay Sharon, Buhler, Douglas D.Abstract:Field experiments, conducted from 1991 to 1994, generated information on Weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of Weed Seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartWeed, 25.1 (65); common purslane, 15.4 (135); common ragWeed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigWeed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotWeed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June
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Weed Seedbanks of the U.S. Corn Belt: Magnitude, Variation, Emergence, and Application
Iowa State University Digital Repository, 1992Co-Authors: Forcella Frank, Wilson, Robert G., Renner, Karen A., Dekker, Jack H., Harvey, Robert G., Alm, David A., Buhler, Douglas D., Cardina JohnAbstract:Seedbanks and seedling emergence of annual Weeds were examined in arable fields at eight locations in the Corn Belt. Seed densities were estimated by direct seed extraction from each of several soil cores in each sampled plot. Average total seedbank densities ranged from 600 to 162 000 viable seed m⁻² among locations. Coefficients of variation (CV) typically exceeded 50%. CV for seed densities of individual species usually exceeded 100%, indicating strongly aggregated distributions. CV were lower for species with dense seed populations than those with sparse seed populations. Variance of total seedbank densities was unstable when \u3c 10 cores were examined per plot, but stabilized at all locations when ≥ 15 cores were analyzed, despite a 12-fold difference in plot size and 270-fold difference in seed density among locations. Percentage viable seed that emerged as seedlings in field plots ranged from \u3c 1% for yellow rocket to 30% for giant foxtail. Redroot pigWeed and common lambsquarters were the most frequently encountered species. Emergence percentages of these species were related inversely to rainfall or air temperatures in April or May, presumably because anoxia and/or high temperatures induced secondary dormancy in nondormant seed. From 50 to 90% of total seed in the seedbank were dead. This information can be employed by bioeconomic Weed management models, which currently use coarse estimates of emergence percentages to customize recommendations for Weed control