@article{riar_spears_burns_jordan_zhang_rufty_2014, title={Persistence of Benghal dayflower (Commelina benghalensis) in sustainable agronomic systems: Potential impacts of hay bale storage, animal digestion, and cultivation}, volume={38}, DOI={10.1080/21683565.2013.839486}, abstractNote={Experiments were conducted to evaluate factors affecting persistence of the invasive, federal noxious weed Benghal dayflower in sustainable agronomic systems. Seeds were exposed to a range of temperatures simulating those found in hay bales in the field and periodically tested for viability over 21 days. Seeds were nonviable after one day at 65 °C and after 14 days at 50 or 45 °C. A second series of experiments examined the effects of simulated rumen digestion on germination and viability of Benghal dayflower seeds and the response was compared to that with seeds of five other common weed species. Time courses revealed that seeds from the other weeds were acutely damaged by digestion and viability depressed after 48 and 96 h, but germination of Benghal dayflower seeds was increased at 48 h, and only a slight decrease occurred after 96 h. In the third experimental series, stem fragments of Benghal dayflower were buried in soil at 2 and 6 cm depths and exposed to aerial temperatures of 20, 25, 30, and 35 °C for 30 days. Root development occurred at both depths, but leaf development was restricted at 6 cm and subterranean spathe development was not found at 2 cm. Temperatures higher than 25 °C favor regeneration at both depths. The results, collectively, show the difficulty encountered when trying to control or eradicate Benghal dayflower in sustainable farming systems. Farms must avoid using fresh hay as animal feed when Benghal dayflower is present in hay fields, as little restraint on seed viability will be exerted during digestion and generation of manure. Cultivation is unlikely to be an effective control strategy during summer months when Benghal dayflower is growing most aggressively, because soil temperatures are optimal for vegetative regeneration.}, number={3}, journal={Agroecology and Sustainable Food Systems}, author={Riar, M. K. and Spears, J. F. and Burns, J. C. and Jordan, D. L. and Zhang, C. X. and Rufty, T. W.}, year={2014}, pages={283–298} }
 @article{clewis_jordan_spears_wilcut_2007, title={Influence of environmental factors on cutleaf eveningprimrose (Oenothera laciniata) germination, emergence, development, vegetative growth, and control}, volume={55}, ISSN={["1550-2759"]}, DOI={10.1614/WS-06-089}, abstractNote={Abstract Laboratory and greenhouse studies were conducted to determine the effect of temperature, solution pH, water stress, and planting depth on cutleaf eveningprimrose germination and emergence. Field studies were conducted to measure growth parameters of cutleaf eveningprimrose throughout the fall season. When treated with constant temperature, cutleaf eveningprimrose germinated over a range of 15 to 32 C, with the optimum germination occurring at 24 C. Onset, rate, and total germination were greatest in an alternating 20/35 C temperature regime. Germination decreased as solution pH increased, with greatest germination occurring at solution pH of 4. Germination decreased when cutleaf eveningprimrose seed was subjected to increased water stress. Emergence was optimum when seed were buried at depths of 0.5 cm. Germination decreased with increasing burial depth, and no seed emerged from a depth of 10 cm. Cutleaf eveningprimrose control was maximized when 2,4-D was applied in mixture with glyphosate or pa...}, number={3}, journal={WEED SCIENCE}, author={Clewis, S. B. and Jordan, D. L. and Spears, J. F. and Wilcut, J. W.}, year={2007}, pages={264–272} }
 @article{burke_thomas_burton_spears_wilcut_2006, title={A seedling assay to screen aryloxyphenoxypropionic acid and cyclohexanedione resistance in johnsongrass (Sorghum halepense)}, volume={20}, ISSN={["0890-037X"]}, DOI={10.1614/WT-05-160.1}, abstractNote={A seedling bioassay was developed for the rapid diagnosis of resistance to clethodim and fluazifop-P in johnsongrass. The assay was based on differences in the coleoptile length of susceptible (S) and resistant (R) seedlings exposed to clethodim and fluazifop-P in petri dishes for 5 d. Bioassay concentrations of 0.09 mg/L clethodim and 0.18 mg/L fluazifop-P were chosen as discriminant based on rate responses of each biotype to increasing herbicide dose. At 5 d after treatment (DAT), the amounts of clethodim required to reduce coleoptile length by 50% ( GR 50 ) for the R and S seedlings were 462.5 and 24.8 mg/L, respectively, resulting in an R:S ratio of 18.7. The fluazifop GR 50 values for the R and S seedlings were 618.7 and 17.5 mg/L, respectively, resulting in a R:S ratio of 35.4.}, number={4}, journal={WEED TECHNOLOGY}, author={Burke, Ian C. and Thomas, Walter E. and Burton, James D. and Spears, Janet F. and Wilcut, John W.}, year={2006}, pages={950–955} }
 @article{wilson_burton_spears_york_2006, title={Doveweed (Murdannia nudiflora) germination and emergence as affected by temperature and seed burial depth}, volume={54}, ISSN={["1550-2759"]}, DOI={10.1614/WS-06-091.1}, abstractNote={Doveweed is becoming more common in agronomic crops in North Carolina. Laboratory and greenhouse experiments were conducted to determine the effect of temperature and seed burial depth on doveweed germination and emergence. Germination of lightly scarified seed at constant temperature was well described by a Gaussian model, which estimated peak germination at 28 C. Similar maximum percentage of germination was observed for optimal treatments under both constant and alternating temperatures. Among alternating temperatures, a 35/25 C regime gave greatest germination (77%). In spite of similar average daily temperatures, germination was greater with alternating temperature regimes of 40/30 and 40/35 C (65 and 30%, respectively) than constant temperatures of 36 and 38 C (4 and 0%, respectively). No germination was observed at 38 C constant temperature or for alternating temperature regimes of 20/10 and 25/15 C. Light did not enhance germination. Greatest emergence occurred from 0 to 1 cm, with a reduction in emergence as depth increased to 4 cm. No emergence occurred from 6 cm or greater depth. This information on seedbank dynamics may aid in developing tools and strategies for management.}, number={6}, journal={WEED SCIENCE}, author={Wilson, David G., Jr. and Burton, Michael G. and Spears, Janet E. and York, Alan C.}, year={2006}, pages={1000–1003} }
 @article{thomas_burke_spears_wilcut_2006, title={Influence of environmental factors on slender amaranth (Amaranthus viridis) germination}, volume={54}, DOI={10.1614/ws-05-54.2.316}, abstractNote={Germination response of slender amaranth to temperature, solution pH, moisture stress, and depth of emergence was evaluated under controlled environmental conditions. Results indicated that 30 C was the optimum constant temperature for germination. Germination of slender amaranth seed at 21 d was similar, with 35/25, 35/20, 30/25, and 30/20 alternating temperature regimes. As temperatures in alternating regimes increased, time to onset of germination decreased and rate of germination increased. Slender amaranth germination was greater with acidic than with basic pH conditions. Germination declined with increasing water stress and was completely inhibited at water potentials below −0.6 MPa. Slender amaranth emergence was greatest at depths of 0.5 to 2 cm, but some seeds emerged from as deep as 6 cm. Information gained in this study will contribute to an integrated control program for slender amaranth.}, number={2}, journal={Weed Science}, author={Thomas, W. E. and Burke, I. C. and Spears, J. F. and Wilcut, J. W.}, year={2006}, pages={316–320} }
 @article{lanier_jordan_spears_wells_johnson_2005, title={Peanut response to inoculation and nitrogen fertilizer}, volume={97}, number={1}, journal={Agronomy Journal}, author={Lanier, J. E. and Jordan, D. L. and Spears, J. F. and Wells, R. and Johnson, P. D.}, year={2005}, pages={79–84} }
 @article{lancaster_jordan_spears_york_wilcut_monks_batts_brandenburg_2005, title={Sicklepod (Senna obtusifolia) control and seed production after 2,4-DB applied alone and with fungicides or insecticides}, volume={19}, ISSN={["1550-2740"]}, DOI={10.1614/WT-04-227R}, abstractNote={Experiments were conducted during 1999, 2002, and 2003 to evaluate sicklepod control by 2,4-DB applied alone or in mixture with selected fungicides and insecticides registered for use in peanut. The fungicides boscalid, chlorothalonil, fluazinam, propiconazole plus trifloxystrobin, pyraclostrobin, or tebuconazole and the insecticides acephate, carbaryl, esfenvalerate, fenpropathrin, lambda-cyhalothrin, methomyl, or indoxacarb applied in mixtures with 2,4-DB did not reduce sicklepod control by 2,4-DB compared with 2,4-DB alone. The fungicide azoxystrobin reduced control in some but not all experiments. Sicklepod control was highest when 2,4-DB was applied before flowering regardless of fungicide treatment. Seed production and germination were reduced when 2,4-DB was applied 81 to 85 d after emergence when sicklepod was flowering. Applying 2,4-DB before flowering and at pod set and pod fill did not affect seed production.}, number={2}, journal={WEED TECHNOLOGY}, author={Lancaster, SH and Jordan, DL and Spears, JE and York, AC and Wilcut, JW and Monks, DW and Batts, RB and Brandenburg, RL}, year={2005}, pages={451–455} }
 @article{lanier_jordan_barnes_matthews_grabow_griffin_bailey_johnson_spears_wells_2004, title={Disease management in overhead sprinkler and subsurface drip irrigation systems for peanut}, volume={96}, ISSN={["1435-0645"]}, DOI={10.2134/agronj2004.1058}, abstractNote={Experiments were conducted during 2001 and 2002 at one location in North Carolina to compare development of early leaf spot (Cerco-spora arachidicola Hori), pod yield, and market grade characteristics when peanut (Arachis hypogea L.) was grown under overhead sprinkler irrigation (OSI) and subsurface drip irrigation (SDI) and fungicides were not applied or applied biweekly or based on weather advisories. Incidence of early leaf spot was lower when peanut was grown under SDI compared with OSI when fungicides were not applied. Fewer fungicide applications were needed when applications were based on weather advisories rather than when applied biweekly. There was no difference in early leaf spot control or leaf defoliation resulting from disease when fungicides were applied regardless of irrigation system or fungicide application approach. Pod yield was higher in 2001 under SDI compared with OSI when fungicides were not applied; yield was similar in 2002. Disease severity was much higher in 2001 than in 2002 and most likely explains differences in pod yield between years. No difference in yield was noted when fungicides were applied, regardless of irrigation system. The percentage of extra large kernels (%ELK) was lower in 1 of 2 yr under SDI compared with OSI. There were no differences in percentages of fancy pods (%FP), sound splits (%SS), and other kernels (%OK) among irrigation systems and fungicide programs. In a separate experiment where fungicides were applied biweekly, pod yield, %FP, and %ELK were similar under SDI and OSI but greater than nonirrigated peanut. The %OK was lower when peanut was irrigated.}, number={4}, journal={AGRONOMY JOURNAL}, author={Lanier, JE and Jordan, DL and Barnes, JS and Matthews, J and Grabow, GL and Griffin, WJ and Bailey, JE and Johnson, PD and Spears, JF and Wells, R}, year={2004}, pages={1058–1065} }
 @article{lanier_jordan_spears_wells_johnson_barnes_hurt_brandenburg_bailey_2004, title={Peanut response to planting pattern, row spacing, and irrigation}, volume={96}, ISSN={["1435-0645"]}, DOI={10.2134/agronj2004.1066}, abstractNote={Experiments were conducted from 1999 through 2002 in North Carolina to compare interactions of planting pattern, plant population, and irrigation on peanut (Arachis hypogaea L.) pod yield and market grade characteristics. In additional experiments, pod yield and severity of tomato spotted wilt tospovirus associated with the cultivars NC-V 11, NC 12C, VA 98R, and Perry were compared in single row (rows spaced 91 cm apart) and standard twin row (two rows spaced 18 cm apart on 91-cm centers) planting patterns when peanut was dug and vines inverted on two digging dates spaced 10 to 16 d apart. In a third set of experiments, pod yield, market grade characteristics, and severity of tomato spotted wilt tospovirus were compared when the cultivars NC-V 11 and Perry were planted in single row, standard twin row, and narrow twin row (two rows spaced 18 cm apart on 46-cm centers) planting patterns. Peanut pod yield was higher in standard twin row planting patterns than when grown in single row planting patterns in some but not all experiments. Planting peanut in the narrow twin row pattern did not increase peanut pod yield over the standard twin row planting pattern. Less tomato spotted wilt was observed in standard or narrow twin row planting patterns compared with single row planting patterns. Planting peanut in single rows spaced 46 cm apart did not improve yield over peanut planted in single rows spaced 91 cm apart or the standard twin row planting pattern, regardless of irrigation treatment.}, number={4}, journal={AGRONOMY JOURNAL}, author={Lanier, JE and Jordan, DL and Spears, JF and Wells, R and Johnson, PD and Barnes, JS and Hurt, CA and Brandenburg, RL and Bailey, JE}, year={2004}, pages={1066–1072} }
 @article{burke_thomas_spears_wilcut_2003, title={Influence of environmental factors on after-ripened crowfootgrass (Dactyloctenium aegyptium) seed germination}, volume={51}, ISSN={["0043-1745"]}, DOI={10.1614/0043-1745(2003)051[0342:IOEFOA]2.0.CO;2}, abstractNote={Laboratory and greenhouse studies were conducted to determine the effect of temperature, pH, water stress, and planting depth on crowfootgrass germination. When treated with constant temperature, crowfootgrass germinated over a range of 15 to 40 C, with the optimum germination occurring at 30 C (42%). Onset, rate, and total germination (94%) were greatest in an alternating 20 and 35 C temperature regime. Germination decreased as pH increased, with greatest germination occurring at pH 4 and 5. Germination was reduced when seed was subjected to water stress, and no germination occurred below −0.8 mPa. Emergence was similar when seed were placed on the soil surface or buried at depths of 0.5 or 1 cm. Germination decreased with burial depth, and no seed emerged from 10 cm. These data suggest that crowfootgrass may emerge later in the season with warmer temperatures and after a precipitation event, and may emerge rapidly. These attributes could contribute to poor control later in the season by soil-applied herbicides or allow crowfootgrass to emerge after final postemergence treatments are made.}, number={3}, journal={WEED SCIENCE}, author={Burke, IC and Thomas, WE and Spears, JF and Wilcut, JW}, year={2003}, pages={342–347} }
 @article{burke_thomas_spears_wilcut_2003, title={Influence of environmental factors on broadleaf signalgrass (Brachiaria platyphylla) germination}, volume={51}, ISSN={["1550-2759"]}, DOI={10.1614/0043-1745(2003)051[0683:IOEFOB]2.0.CO;2}, abstractNote={Abstract Laboratory and greenhouse studies were conducted to determine the effect of temperature, solution pH, water stress, and planting depth on broadleaf signalgrass germination. Broadleaf signalgrass seed required removal of the husk for germination. When treated with constant temperature, broadleaf signalgrass germinated over a range of 20 to 35 C, with optimum germination occurring at 30 and 35 C. Onset, rate, and total germination (87%) was greatest in an alternating 20/30 C temperature regime. Germination decreased as solution pH increased, with greatest germination occurring at pH values of 4 and 5. Germination decreased with increasing water potential, and no germination occurred below − 0.8 mPa. Emergence was above 42% when seed were placed on the soil surface or buried 0.5 cm deep. Germination decreased with burial depth, but 10% of broadleaf signalgrass seed emerged from 6.0-cm depth. No seed emerged from 10-cm depth. These data suggest that broadleaf signalgrass may emerge later in the seaso...}, number={5}, journal={WEED SCIENCE}, author={Burke, IC and Thomas, WE and Spears, JF and Wilcut, JW}, year={2003}, pages={683–689} }
 @article{beam_jordan_york_isleib_bailey_mckemie_spears_johnson_2002, title={Influence of prohexadione calcium on pod yield and pod loss of peanut}, volume={94}, DOI={10.2134/agronj2002.9550}, abstractNote={We wish to report an error that occurred on page 333 of the above paper, which appeared in the March–April 2002 issue. In Table 1, data in the “0 g ha−1” row were incorrectly transposed with data in the “140 + 140 g ha−1” row for pod loss and percent pod loss. Combined yield and maximum yield are correct as presented.}, number={2}, journal={Agronomy Journal}, author={Beam, J. B. and Jordan, D. L. and York, A. C. and Isleib, T. G. and Bailey, J. E. and McKemie, T. E. and Spears, J. F. and Johnson, P. D.}, year={2002}, pages={331–336} }
 @article{susko_mueller_spears_2001, title={An evaluation of methods for breaking seed dormancy in kudzu (Pueraria lobata)}, volume={79}, ISSN={["0008-4026"]}, DOI={10.1139/b00-153}, abstractNote={We evaluated several methods for breaking dormancy in seeds of the invasive weed Pueraria lobata (Willd.) Ohwi (kudzu). Seedlings from untreated seeds emerged from late March to early October 1999 in trays placed outdoors under natural weather conditions; mean cumulative percentage emergence was low (11%). In growth chamber experiments, germination percentages of untreated seeds ranged from 6 to 17%. All hand-scarified seeds germinated, whereas only 6% of intact seeds germinated. Other dormancy-breaking methods that produced higher germination percentages included exposure to ethyl alcohol for 6-12 h (24-86%), exposure to concentrated sulfuric acid for 1-2 h (65-81%), and exposure to moist heat for 5-300 s (30-80%). The influence of temperature on germination percentages of seeds following dry heat treatments depended on the duration of exposure. At 60 and 80°C, germination percentages increased with longer exposures to dry heat and were greatest after 720 min (27 and 60%, respectively). At 100°C, percent germination was greatest when seeds were exposed to dry heat for only 10 min (93%). Cold stratification at 5°C for 0-6 weeks did not increase seed germination percentages after exposure to a range of alternating thermoperiods. Similarly, dry storage at room temperature for 0, 200, or 400 days did not affect germination percentages in light or dark treatments.Key words: Pueraria lobata, physical dormancy, germination, phenology, acid scarification, warm stratification, cold stratification.}, number={2}, journal={CANADIAN JOURNAL OF BOTANY-REVUE CANADIENNE DE BOTANIQUE}, author={Susko, DJ and Mueller, JP and Spears, JF}, year={2001}, month={Feb}, pages={197–203} }
 @article{jordan_beam_johnson_spears_2001, title={Peanut response to prohexadione calcium in three seeding rate-row pattern planting systems}, volume={93}, ISSN={["0002-1962"]}, DOI={10.2134/agronj2001.931232x}, abstractNote={Peanut (Arachis hypogaea L.) in the USA is generally grown in single rows spaced 91 to 102 cm apart. Research suggests that pod yield can be increased by growing peanut in twin rows (18-23 cm spacing) on beds spaced 91 to 102 cm apart. Prohexadione Ca (Ca salt of 3,5-dioxo-4-propionylcyclohexanecarboxylic acid) increases row visibility and in some instances increases pod yield and improves market grade factors. Research was conducted to determine response of peanut grown in three seeding rate-row pattern planting systems (single rows at a seeding rate of 120 kg ha -1 or twin rows spaced 18 cm apart on beds spaced 91 cm apart at seeding rates of 145 and 190 kg ha -1 ) to prohexadione Ca applied at 50% row closure. Row visibility increased and main stem height was shorter at the end of the season when prohexadione Ca was applied in most environments and for most seeding rate-row pattern combinations when compared with nontreated peanut. Pod yield and gross economic value increased 160 kg ha -1 and $96 ha -1 , respectively, when prohexadione Ca was applied irrespective of the seeding rate-row pattern combination or environment. Prohexadione Ca also increased the percentage of extra large kernels (% ELK) but did not affect percentages of sound mature kernels (SMK), other kernels (OK), sound splits (SS), or total sound mature kernels (TSMK). Seeding rate-row pattern combination affected pod yield, market grade, and gross economic value although a consistent trend was not apparent.}, number={1}, journal={AGRONOMY JOURNAL}, author={Jordan, DL and Beam, JB and Johnson, PD and Spears, JF}, year={2001}, pages={232–236} }
 @article{wilcut_askew_bailey_spears_isleib_2001, title={Virginia market-type peanut (Arachis hypogaea) cultivar tolerance and yield response to flumioxazin preemergence}, volume={15}, ISSN={["1550-2740"]}, DOI={10.1614/0890-037X(2001)015[0137:VMTPAH]2.0.CO;2}, abstractNote={Field studies were conducted in 1996 and 1997 to evaluate response of eight peanut cultivars to flumioxazin applied preemergence (PRE) at 71 g ai/ha. Peanut cultivars evaluated include ‘NC 12C’, ‘NC 7’, ‘VAC 92R’, ‘NC-V 11’, ‘NC 10C’, ‘AT VC 1’, ‘NC 9’, and the experimental breeding line ‘N9001OE’. Visible injury 3 wk after planting in 1996 was 3% or less regardless of cultivar. In 1997, all cultivars were injured 15 to 28% with flumioxazin PRE, except VC 1, which was injured 45%. No visible injury was observed at 5 and 9 wk after planting. Flumioxazin did not influence the incidence of early leaf spot, late leaf spot, southern stem rot, cylindrocladium black rot, or tomato spotted wilt virus. Flumioxazin did not affect percentage of extra-large kernels, sound mature kernels, other kernels, and total yield.Nomenclature: Flumioxazin; peanut, Arachis hypogaea L., ‘NC 12C’, ‘NC 7’, ‘VAC 92R’, ‘NC-V 11’, ‘NC 10C’, ‘AT VC 1’, ‘NC 9’, ‘N9001OE’.Additional index words: Disease interaction, Cylindrocladium crotalariae (Loos) Bell and Sobers, Cercospora arachidicola Hori, Cercosporidium personatum (Berk. and Curt.), Sclerotium rolfsii Sacc., grade parameters, extra-large kernels, sound mature kernels, sound splits, total kernels, other kernels, fancy pods.Abbreviations: CBR, cylindrocladium black rot; DAP, days after planting; ELK, extra-large kernels; PPI, preplant incorporated; PRE, preemergence; SMK, sound mature kernels; SS, sound splits; TMSK, total sound mature kernels; TSWV, tomato spotted wilt virus; WAP, weeks after planting.}, number={1}, journal={WEED TECHNOLOGY}, author={Wilcut, JW and Askew, SD and Bailey, WA and Spears, JF and Isleib, TG}, year={2001}, pages={137–140} }
 @article{bailey_wilcut_spears_isleib_langston_2000, title={Diclosulam does not influence yields in eight virginia market-type peanut (Arachis hypogaea) cultivars}, volume={14}, ISSN={["1550-2740"]}, DOI={10.1614/0890-037x(2000)014[0402:ddniyi]2.0.co;2}, abstractNote={Abstract: Field studies were conducted in 1996 and 1997 to evaluate response of eight peanut cultivars to diclosulam applied preplant incorporated at 36 g ai/ha in a weed-free environment. Peanut cultivars evaluated included ‘NC 12C’, ‘NC 7’, ‘VAC 92R’, ‘NC-V 11’, ‘NC 10C’, ‘AT VC 1’,‘NC 9’, and the experimental breeding line N90010E. Visible injury 3 wk after planting was less than 5% regardless of cultivar. No injury was observed at 21 d after planting. Diclosulam did not influence the incidence of early leaf spot, late leaf spot, southern stem rot, cylindrocladium black rot, or tomato spotted wilt virus. Diclosulam did not affect percentage of extra large kernels, sound mature kernels, other kernels, and yield. Nomenclature: Diclosulam; peanut, Arachis hypogaea L. NC 12C, NC 7, VAC 92R, NC-V 11, NC 10C, AT VC 1, NC 9, N90010E. Additional index words: Disease interaction, cylindrocladium black rot, Cylindrocladium crotalariae (Loos) Bell et Sobers, early leaf spot, Cercospora arachidicola Hori, late lea...}, number={2}, journal={WEED TECHNOLOGY}, author={Bailey, WA and Wilcut, JW and Spears, JF and Isleib, TG and Langston, VB}, year={2000}, pages={402–405} }
 @article{mueller_hall_spears_penny_2000, title={Winter establishment of eastern gamagrass in the southern Piedmont}, volume={92}, ISSN={["0002-1962"]}, DOI={10.2134/agronj2000.9261184x}, abstractNote={Eastern gamagrass [Tripsacum dactyloides (L.)] has the potential to contribute as a warm-season component in grazing systems and conservation plantings, but its seeds exhibit a strong dormancy that reduce germination and successful stand establishment. A 3-yr study was conducted on Typic Hapudult soils to determine the influence of fungicide seed treatment [Captan (N-trichloromethylthio-4-cyclohexene-1,2-dicarboximide), 5.6 g a.i. kg−1 seed] and winter planting date (November–February) on germination, stand establishment, and herbage mass of eastern gamagrass. Eastern gamagrass was planted with and without fungicide seed treatment at monthly intervals between November and May. The May plantings (stratified and nonstratified seeds) served as controls. Fungicide seed treatment had no effect on initial or subsequent stands of eastern gamagrass. Winter plantings resulted in initial stands that were equal or superior to stands established from planting stratified seeds in May (5.9 vs. 3.4 plants m−2, respectively). Significant seed carry-over effects were observed from spring (April and May) plantings, with an average of 8.8 seedlings m−2 germinating in spring of the second year compared with 1.7 seedlings m−2 for winter treatments. Herbage mass for spring plantings (March, April, and May) was depressed up to 75% compared with winter plantings. Planting in November, December, or January is an effective alternative to planting stratified seeds in May in the southern Piedmont.}, number={6}, journal={AGRONOMY JOURNAL}, author={Mueller, JP and Hall, TS and Spears, JF and Penny, BT}, year={2000}, pages={1184–1188} }
 @article{spears_tekrony_egli_1997, title={Temperature during seed filling and soybean seed germination and vigour}, volume={25}, number={2}, journal={Seed Science and Technology}, author={Spears, J. F. and Tekrony, D. M. and Egli, D. B.}, year={1997}, pages={233–244} }