The Botanical Review

, Volume 59, Issue 4, pp 251–272 | Cite as

Tree invasion and establishment in old fields at Hutcheson Memorial Forest

  • Randall W. Myster
Article

Abstract

In this review I present results from pattern analysis and field experiments in New Jersey, United States concerning tree invasion and establishment in old fields. Hutcheson Memorial Forest Center (HMF) is the New Jersey study site and a logical choice to anchor a review of this topic. HMF contains the longest and largest old field permanent plot study in the USA including extensive data concerning tree invasion and establishment. HMF has also been the site of considerable old field tree experimental research. In addition, I review other investigations of old field tree invasion and establishment of the eastern deciduous biome and contrast them with HMF. I identify critical questions concerning tree invasion and establishment, indicate what progress has been made towards answering these questions and propose future experimentation. I also synthesize results into a conceptual model and investigate the relative importance of seed and seedling processes in determining tree dynamics in old fields.

The idea of a possibility or “window” for tree invasion and establishment and its variation form the basis for this review. For example, the temporal variation of windows is reflected in tree establishment patterns at HMF because wind- and bird-dispersed species invaded one year after cessation of cultivation while mammal-dispersed species were not present until year 12. Although analysis of size classes of individual HMF trees imply that windows close quickly, studies are of too short duration to tell definitely. Spatial variation in invasion and establishment pattern includes exponential decline in seed and stem density with distance from forest edge which deteriorates with time as the old field becomes more structurally complex. Additional spatial heterogeneity occurs when seeds and seedlings of bird-dispersed species clump which conversely becomes more pronounced with time. Many of these HMF patterns are seen in other eastern United States old field sites.

When reviewing field experiments from my site and others, I focus on the spatial and temporal variation and the difference between species in the effect of processes on tree seeds and seedlings. I do this because this variation relates directly to the dynamic nature of windows whose quantification is necessary for modeling. Combining my pattern analysis with a survey of variation in seed and seedling mortality caused by different successional processes in old fields, I conclude that seed dispersal, conditions necessary for seed germination and seed and seedling predation are the critical processes controlling and constraining tree invasion and establishment in old fields. Competition and indirect effects of litter and the environment, which modify how these processes affect tree dynamics, are also important. Therefore, processes involving the interaction of species with the environment and with other species form the principal filters on and limitations to tree invasion and establishment and not the non-interactive life-history traits of individual tree species such as growth rate or longevity. The interaction of pattern and process and the affect of many of these processes on old field community structure are also discussed.

Resumen

En este estudio presento los resultados de análisis de patrones y experimentos de campo en New Jersey, Estados Unidos relacionados con la invasión y establecimiento de árboles en campos abandonados. Hutcheson Memorial Forest Center (HMF) en New Jersey es una alternativa lógica para desarrollar este tópico. HMF contiene el area de estudios relacionados con el monitoreo de vegetación en campos abandondos más grande y de más larga historia. HMF también ha sido el sitio de investigatión de arboles en campos abandonados por décadas. También estudie otras investigaciones de invasión y establecimiento de arboles en campos abandonados en un bioma forestal del este y los comparé con los de HMF. Identifico preguntas críticas sobre la invasión y establecimiento de árboles, indico cual es el progreso hecho en contestarlas y propongo experimentos futuros. Finalmente, yo sintetizo los resultados en un modelo conceptual e investigo el papel que juegan los procesos a nivel de semillas y plántulas en la dinámica de arboles en los campos abandonados.

Las ideas de la oportunidad de una invasión y establecimiento de árboles y su tiempo de invasión forman la base para este estudio. Por ejemplo, la variedad del tiempo de invasión se refleja en los patrones de establecimiento de los arboles en HMF. Porque las especies de arboles dispersadas por el viento y aves invadieron un ano despues de la cosecha mientras que las especies dispersadas por mamiferos invadieron despues 12 anos. Aunque el análisis de los tamanos de los árboles en HMF implica que la oportunidad de invasión no dura mucho, es to no se puede con cluir ya que los estudios fueron de muy corta duración. La variación espacial en el patrón de invasión y establecimiento de los arboles tiene una reductión exponencial en la densidad de semillas y tallos de donde termina el bosque. Esta reducción se desvanece según la estructura del campo abandonado se complica can el tiempo. En contraste, un patrón espacial que se hace mas aparente con el tiempo es el amontonamiento de semillas y plántulas dispersas por aves. Muchos de estos patrones son observados en otros campos abandonados en el este de Estados Unidos.

Cuando reviso los experimentos en el campo de HMF y de otros lugares, enfoco el efecto que tienen la variedad en tiempo y espacio de la invasión y la diferencia entre las especies de árboles en los proceso a nivel de semillas y plántulas. Esta variedad se relaciona directamente con la naturaleza dinámica de las oportunidades de invasión cuya cuantificación es necesaria para hacer el modelo. Combiné mi análisis de los patrones con un estudio de variación en la mortalidad de las semillas y plántulas causadas por diferentes procesos sucesivos en campos abandonados. Concluí que la dispersión de semillas, las condiciones críticas para la germination de semillas y el consumo de semillas y plántulas son los procesos críticos que controlan la invasión y establecimiento de árboles en los campos abandonados. La competencia entre plantas y los efectos indirectes del ambiente y de la capa de vegetación muerta en el suelo, modifican cómo los procesos de dispersión, germinación y consumo afectan la dinámica de los árboles. Por lo tanto, son las interacciones de las especies con el ambiente u otras especies las que controlan la invasión y establecimiento de árboles y no las características de las diferentes especies tales como el incremento en crecimiento o longetividad. Las interacciones de patrones y procesos con la estructura de la comunidad en campos abandonados estan discutidos también.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Literature Cited

  1. Alexander, R.E. 1969. Seedfall and establishment in clearcut openings: A case history. USDA Forest Service Research Paper RM-53, Fort Collins, Colorado.Google Scholar
  2. Armesto, J.J. &S.T.A. Pickett. 1985. The effect of intensity of disturbance on old-field species richness. Ecology66: 230–240.CrossRefGoogle Scholar
  3. Bahari, Z.A., Pallardy, S.G. &W.C. Parker. 1985. Photosynthesis, water relations and drought adaptation in six woody species of Oak-Hickory forests in Central Missouri. Forest Sci.31: 557–569.Google Scholar
  4. Bard, G.E. 1952. Secondary succession on the Piedmont of New Jersey. Ecol. Monogr.22: 195–215.CrossRefGoogle Scholar
  5. Barnes, B.V. 1966. The clonal growth habit of American aspen. Ecology47: 439–447.CrossRefGoogle Scholar
  6. Barnett, R.J. 1977. The effect of burial by squirrels on germination and survival of Oak and Hickory nuts. Amer. Midl. Naturalist98: 319–330.CrossRefGoogle Scholar
  7. Bazzaz, F.A. 1968. Succession on abandoned fields in the Shawnee Hills, southern Illinois. Ecology49: 924–936.CrossRefGoogle Scholar
  8. — 1979. The physiological ecology of plant succession. Annu. Rev. Ecol. Syst.10: 351–371.CrossRefGoogle Scholar
  9. Beckwith, S.L. 1954. Ecological succession on abandoned farmlands and its relationship to wildlife management. Ecol. Monogr.24: 349–376.CrossRefGoogle Scholar
  10. Berkowitz, A.R., C.D. Canham &V.R. Kelly. 1990. Net effects of oldfield vegetation on tree seedling growth and survival. Bull. Ecol. Soc. Amer.71: 90–91.Google Scholar
  11. Billings, W.D. 1938. The structure and development of oldfield shortleaf pine stands and certain associated physical properties of the soil. Ecol. Monogr.8: 437–499.CrossRefGoogle Scholar
  12. Bonck, J. &W.T. Penfound. 1945. Plant succession on abandoned farmland in the vicinity of New Orleans, Louisiana. Amer. Midl. Naturalist33: 520–529.CrossRefGoogle Scholar
  13. Bormann, F.H. 1953. Factors determining the role of loblolly pine and sweetgum in early oldfield succession in the Piedmont of North Carolina. Ecol. Monogr.23: 339–358.CrossRefGoogle Scholar
  14. Buell, M.F., H.F. Buell, J.A. Small &T.G. Siccama. 1971. Invasion of trees in secondary succession on the New Jersey piedmont. Bull. Torrey Bot. Club.98: 67–74.CrossRefGoogle Scholar
  15. Burton, P.J. 1989. Constraints to tree invasion on a nutrient rich site during old-field succession. Ph.D. dissertation. University of Illinois, Urbana.Google Scholar
  16. — &F.A. Bazzaz. 1991. Tree seedling emergence on interactive temperature and moisture gradients and in patches of old-field vegetation. Amer. J. Bot.78: 131–149.CrossRefGoogle Scholar
  17. Byrd, M.A. 1956. Relation of ecological succession to farm game in Cumberland County in the Virginia Piedmont. J. Wildlife Managern.20: 188–195.CrossRefGoogle Scholar
  18. Canham, C.D. &D.M. Wood. 1988. Variation in rates of tree seedling invasion in shrub and herb communities of southeastern New York. Bull. Ecol. Soc. Amer.69: 91.Google Scholar
  19. — &J.D. Hill. 1990. Demographic consequences of herbivory and dieback for tree seedling invasion in oldfields. Bull. Ecol. Soc. Amer.71: 113.Google Scholar
  20. Christensen, N.L. 1977. Changes in structure, pattern and diversity associated with climax forest maturation in piedmont, North Carolina. Amer. Midl. Naturalist97: 176–188.CrossRefGoogle Scholar
  21. Coile, T.S. 1940. Soil changes associated with loblolly pine succession on abandoned agricultural land of the Piedmont Plateau. Bull. School Forest. Duke Univ.5: 1–85.Google Scholar
  22. Connell, J.H. &R.O. Slatyer. 1977. Mechanisms of succession in natural communities and their role in community stability and organization. Amer. Naturalist111: 1119–1144.CrossRefGoogle Scholar
  23. Crafton, W.M. &B.W. Wells. 1934. The oldfield prisere: an ecological study. J. Elisha Mitchell Sci. Soc.49: 225–246.Google Scholar
  24. Davison, S.E. 1981. Tree seedling survivorship at Hutcheson Memorial Forest New Jersey. William L. Hutcheson Mem. Forest Bull.6: 4–7.Google Scholar
  25. Debussche, M., J. Escarre, &J. Lepart, 1980. Changes in Mediterranean shrub communities withCytisus purgens andGenista scoparius. Vegetatio43: 73–82.CrossRefGoogle Scholar
  26. De Steven, D. 1991a. Experiments on mechanisms of tree establishment in successional old fields:seedling emergence. Ecology72: 1066–1075.CrossRefGoogle Scholar
  27. —. 1991b. Experiments on mechanisms of tree establishment in successional old fields: seedling survival and growth. Ecology72: 1076–1088.CrossRefGoogle Scholar
  28. Drew, W.B. 1942. The vegetation of abandoned cropland in Cedar Creek area, Boone and Callaway Counties, Missouri. University Missouri College Agricultural Exp. Sta. Res. Bull. 344.Google Scholar
  29. Drury, W.H. &I.C.T. Nisbet. 1973. Succession. J. Arnold Arbor.54: 331–368.Google Scholar
  30. Duncan, W.H. 1935. Root systems of woody plants of oldfields of Indiana. Ecology16: 554–567.CrossRefGoogle Scholar
  31. Egler, F.E. 1954. Vegetation science concepts I. Initial floristic composition, a factor in oldfield vegetation development. Vegetatio4: 412–417.CrossRefGoogle Scholar
  32. Eissenstat, D.M. &J.E. Mitchell. 1983. Effects of seedling grass and clover on growth and water potential of Douglas-fir seedlings. Forest Sci.29: 166–179.Google Scholar
  33. Facelli, J.M. &W.C. Carson. 1991. Spatial patterns of litter accumulation in a New Jersey oldfield. Bull. Torrey Bot. Club.118: 62–66.CrossRefGoogle Scholar
  34. — &S.T.A. Pickett. 1989. The effects of litter and competition on the establishment of woody seedlings during oldfield succession. Bull. Ecol. Soc. Amer.70: 108.Google Scholar
  35. — &S.T.A. Pickett. 1991. Interactions after death: effects of litter on plant competition and woody seedling predation. Bull. Ecol. Soc. Amer.72: 110.Google Scholar
  36. Finegan, B. 1984. Forest succession. Nature312: 109–114.CrossRefGoogle Scholar
  37. Fisher, R.F., R.A. Woods &M.R. Glavicic. 1978. Allelopathic effects of goldenrod and aster on young sugar maple. Canad. J. Forest Res.8: 1–9.CrossRefGoogle Scholar
  38. Frank, R.M. &L.O. Safford. 1970. Lack of viable seeds on the forest floor after clearcutting. J. Forest (Washington)68: 776–778.Google Scholar
  39. Fowells, H.A. 1965. Silvics of forest trees of the United States. Agriculture Handbook 271. Forest Service, U.S.D.A. Washington, D.C.Google Scholar
  40. Gant, R.E. &E.E.C. Clebsch. 1975. The allelopathic influences ofSassafras albidum in oldfield succession in Tennessee. Ecology56: 604–615.CrossRefGoogle Scholar
  41. Gholz, H.L., G.M. Hawk, A. Campbell, K. Cromack &A. T. Brown. 1985. Early vegetation recovery and element cycles on a clearcut watershed in western Oregon. Canad. J. Forest Res.15: 400–409.CrossRefGoogle Scholar
  42. Gifford, G. 1966. Aspen root studies on three sites in northern Utah. Amer. Midl. Naturalist75: 132–141.CrossRefGoogle Scholar
  43. Gill, D.S. &P.L. Marks. 1991. Tree and shrub seedling colonization of old fields in central New York. Ecol. Monogr.61: 183–205.CrossRefGoogle Scholar
  44. Gleason, H.A. 1927. Further views on the succession concept. Ecology8: 299–326.CrossRefGoogle Scholar
  45. Grime, J.P. 1979. Plant strategies and vegetation processes. Wiley, New York.Google Scholar
  46. Gross, K.L. 1980. Colonization by Verbascum thapsus (Mullein) of an oldfield in Michigan: experiments of the effects of vegetation. J. Ecol.68: 919–927.CrossRefGoogle Scholar
  47. Grubb, P.J. 1977. The maintenance of species-richness in plant communities: the importance of the regeneration niche. Biol. Rev. Cambridge Philos. Soc.52: 107–145.CrossRefGoogle Scholar
  48. Hanson, J.C., J.A. Bailey, &R.J. Siglin. 1969. Activity and use of habitat by radio-tagged cottontails during winter. Trans. Illinois State Acad. of Sci.62: 294–302.Google Scholar
  49. Harper, J.L. 1977. Population biology of plants. Academic Press, New York.Google Scholar
  50. Harrison, J.S. &P.A. Werner. 1982. Colonization by oak seedlings into a heterogeneous successional habitat. Canad. J. Bot.62: 559–563.Google Scholar
  51. Hill, J.D. &C.D. Canham. 1989. Demography of tree seedling invasion of old-field communities along utility right-of-ways in southeastern New York. Bull. Ecol. Soc. Amer.70: 142.Google Scholar
  52. Holthuijzen, A.M.A. &T.L. Sharik. 1985. Colonization of abandoned pastures by eastern red cedar (Juniperus virginiana L.). Canad. J. Forest Res.15: 1065–1068.CrossRefGoogle Scholar
  53. Horn, H.S. 1974. The ecology of secondary succession. Annual Rev. Ecol. Syst.5: 25–37.CrossRefGoogle Scholar
  54. Hughes, J.W. &T.J. Fahey. 1988. Seed dispersal and colonization in a disturbed northern hardwood forest. Bull. Torrey Bot. Club.115: 89–99.CrossRefGoogle Scholar
  55. Huston, M.A. &D.L. Deanglis 1987. Size bimodality in monospecific plant populations: a critical review of potential mechanisms. Amer. Naturalist129: 678–707.CrossRefGoogle Scholar
  56. Johnstone, I.M. 1988. Plant invasion windows: a time-based classification of invasion potential. Biol. Rev. (London)61: 369–394.Google Scholar
  57. Keever, C. 1979. Mechanisms of plant succession on old fields of Lancaster County Pennsylvania. Bull. Torrey Bot. Club.106: 299–308.CrossRefGoogle Scholar
  58. Korstian, C.F. 1927. Factors controlling germination and early survival in Oaks. Bull. Yale Univ. School Forest. 19.Google Scholar
  59. Livingston, R.B. &M.U. Allessio. 1968. Buried viable seed in successional field and forest stands, Harvard Forest, Massachusetts. Bull. Torrey Bot. Club.95: 58–69.CrossRefGoogle Scholar
  60. Louda, S.M. 1982. Distribution ecology: Variation in plant recruitment over a gradient in relation to insect seed predation. Ecol. Monogr.52: 25–41.CrossRefGoogle Scholar
  61. Lutz, H.J. 1928. Trends and silvicultered significance of upland forest succession in southern New England. Bull. Yale Univ. School Forest.22: 1–68.Google Scholar
  62. Matheron, G. 1963. Principles of Geostatistics. Econ. Geol.58: 1246–1266.CrossRefGoogle Scholar
  63. McCarthy, B.C. &J.M. Facelli. 1990. Microdisturbances in old fields and forests: Implications for woody seedling establishment. Oikos58: 27–33.CrossRefGoogle Scholar
  64. McCormick, J. 1968. Succession. VIA 1, pages 22–35, 131–132. Student Publication, Graduate School of Fine Arts, University Pennsylvania.Google Scholar
  65. McDonnell, M.J. &H.F. Buell. 1984. Patterns of woody plant establishment over 20 years of old field succession in central New Jersey. Bull. Ecol. Soc. Amer.65: 66.Google Scholar
  66. — &E.W. Stiles. 1983. The structural complexity of oldfield vegetation and the recruitment of bird-dispersed plant species. Oecologia56: 109–116.CrossRefGoogle Scholar
  67. — &J. Koch. 1990. The effect of corridor width on dispersal dynamics of tree seeds. Bull. Ecol. Soc. Amer.71: 246.Google Scholar
  68. McIntosh, R.P. 1980. The relationship between succession and the recovery process in ecosystems, pages 11–62.in J. Cairns (ed.) The recovery process in damaged ecosystems. Ann Arbor Science Publishers, Inc. Ann Arbor, Mich.Google Scholar
  69. McQuilken, W.E. 1940. The natural establishment of pine in abandoned fields in the Piedmont Plateau region. Ecology21: 135–147.CrossRefGoogle Scholar
  70. Meadows, M.A. 1988. Effects of mammalian herbivores on natural densities of woody seedlings in an old-field plant community. Bull. Ecol. Soc. Amer.69: 229.Google Scholar
  71. —,R. Waynor &S.T.A. Pickett. 1989. Effect ofSylvilagus floridanus herbivory on woody seedling survival in an oldfield community patch. Bull. Ecol. Soc. Amer.70: 200.Google Scholar
  72. Miles, J. 1979. Vegetation dynamics. John Wiley and Sons, New York.Google Scholar
  73. Myster, R.W. &B.C. McCarthy. 1989. Effects of herbivory and competition on survival ofCarya tomentosa (Juglandaceae) seedlings. Oikos56: 145–148.CrossRefGoogle Scholar
  74. — &S.T.A. Pickett. 1988. Individualistic patterns of annuals and biennials in early successional old fields. Vegetatio78: 53–60.CrossRefGoogle Scholar
  75. — &S.T.A. Pickett. 1989. The Buell successional study at Hutcheson Memorial Forest Center. Permanent Plotter3: 2–3 (Published as part of the Newsletter of the Vegetation Section, Ecological Society of America. Tempe, Arizona).Google Scholar
  76. — &S.T.A. Pickett. 1990. Initial conditions, history and successional pathways in ten contrasting old fields. Amer. Midl. Naturalist124: 231–238.CrossRefGoogle Scholar
  77. — &S.T.A. Pickett. 1992a. Effects of payability and dispersal mode on spatial patterns of trees in old fields. Bull. Torrey Bot. Club.119: 145–151.CrossRefGoogle Scholar
  78. — &S.T.A. Pickett. 1992b. Dynamics of associations between plants in ten old fields during 31 years of succession. J. Ecol.80: 291–302.CrossRefGoogle Scholar
  79. — &S.T.A. Pickett. 1993. Effects of litter, distance, density and vegetation patch type on postdispersal tree seed predation in old fields. Oikos66: 381–388.CrossRefGoogle Scholar
  80. Newman, J.A., G.M. Recer, S.M. Zwicker, &T. Caraco. 1988. Effects of predation hazard on foraging constraints: patch-use strategies in grey squirrels. Oikos53: 93–97.CrossRefGoogle Scholar
  81. Noble, I.R. &R.O. Slatyer. 1980. The use of vital attributes to predict successional changes in plant communities subject to recurrent disturbances. Vegetatio43: 5–21.CrossRefGoogle Scholar
  82. Olmsted, C.E. 1937. Vegetation of certain sand plains of Connecticut. Bot. Gaz.99: 209–300.CrossRefGoogle Scholar
  83. Oosting, H.J. 1942. An ecological analysis of the plant communities of Piedmont, North Carolina. Am. Midl. Naturalist28: 1–126.CrossRefGoogle Scholar
  84. — &M.E. Humphreys. 1940. Buried viable seeds in a successional series of old field and forest soils. Bull. Torrey Bot. Club.67: 254–273.CrossRefGoogle Scholar
  85. Ormsbee, P., F.A. Bazzaz, &W.R. Boggess. 1976. Physiological ecology ofJuniperus virginiana in old fields. Oecologia23: 75–82.Google Scholar
  86. Parrish, J.A.D. &F.A. Bazzaz. 1982. Niche responses of early and late successional tree seedlings on three resource gradients. Bull. Torrey Bot. Club.109: 451–456.CrossRefGoogle Scholar
  87. Pickett, S.T.A. 1976. Succession: An evolutionary interpretation. Amer. Naturalist110: 107–119.CrossRefGoogle Scholar
  88. —. 1982. Population patterns through twenty years of old field succession. Vegetatio49: 45–59.CrossRefGoogle Scholar
  89. —,S.L. Collins &J.J. Armesto. 1987. Models, mechanisms and pathways of succession. Bot. Rev.53: 335–371.Google Scholar
  90. — &J.S. Kempf. 1980. Branching patterns in forest shrubs and understory trees in relation to habitat. New Phytol.86: 219–228.CrossRefGoogle Scholar
  91. — &M.J. McDonnell. 1989. Changing perspectives in community dynamics: A theory of Successional Forces. Trends in Ecology and Evolution4: 241–245.CrossRefGoogle Scholar
  92. Putz, F.E. &C.D. Canham. 1990. Arrested succession in shrublands: root and shoot competition between shrubs and trees. Bull. Ecol. Soc. Amer.71: 292.Google Scholar
  93. Pound, C.E. &F.E. Egler. 1953. Brush control in southeastern New York fifteen years of stable tree-less communities. Ecology34: 63–73.CrossRefGoogle Scholar
  94. Quarterman, E. 1957. Early plant succession on abandoned cropland in the central basis of Tennessee. Ecology38: 300–309.CrossRefGoogle Scholar
  95. Rankin, W.T. 1981. Differential predation of first year woody seedlings along a successional gradient. Bull. New Jersey Acad. Sci.26: 71.Google Scholar
  96. Rankin, W.T. &S.T.A. Pickett. 1989. Time of establishment of red maple (Acer rubrum) in early old field succession. Bull. Torrey Bot. Club.116: 182–186.CrossRefGoogle Scholar
  97. Rice, E.L. 1974. Allelopathy. Academic Press, New York.Google Scholar
  98. Schopmeyer, C.S. 1974. Seeds of woody plants in the United States. Agriculture handbook no. 450. Forest Service, U.S.D.A. Washington, D.C. USA.Google Scholar
  99. Schupp, E.W. 1990. Annual variation in seed fall, postdispersal predation, and recruitment of a neotropical tree. Ecology71: 504–515.CrossRefGoogle Scholar
  100. Spurr, S.H. 1956. Forest associations in the Harvard Forest. Ecol. Monogr.26: 245–262.CrossRefGoogle Scholar
  101. Stallard, H. 1929. Secondary succession in the climax forest formations of northern Minnesota. Ecology10: 476–547.CrossRefGoogle Scholar
  102. Thompson, J.W. 1943. Plant succession on abandoned fields in the central Wisconsin sand plain area. Bull. Torrey Bot. Club.70: 34–41.CrossRefGoogle Scholar
  103. Tilman, D. 1988. Plant strategies and the dynamics and structure of plant communities. Princeton University Press, Princeton, New Jersey.Google Scholar
  104. Tourney, J.W. &C.F. Korstian. 1937. Foundations of silviculture upon an ecological basis. 2 ed. John Wiley and Sons, New York.Google Scholar
  105. van Allen, F.W. 1970. Methods of successful afforestation of a weed infested clay soil. Forest. Chron.46: 139–143.Google Scholar
  106. Watt, A.S. 1947. Pattern and process in the plant community. J. Ecol.35: 1–22.CrossRefGoogle Scholar
  107. Webb, S.L. &M.F. Willson. 1985. Spatial heterogeneity in post-dispersal predation onPrunus andUvula seeds. Oecologia67: 150–153.CrossRefGoogle Scholar
  108. Werner, P.A. &A.L. Harbeck. 1982. The pattern of tree seedling establishment relative to staghorn sumac cover in Michigan oldfields. Amer. Midl. Naturalist108: 124–132.CrossRefGoogle Scholar
  109. Whitford, P.C. &P.B. Whitford. 1978. Effects of trees on ground cover in oldfield succession. Amer. Midl. Naturalist99: 435–443.CrossRefGoogle Scholar
  110. Zutter, B.R., G.R. Glover &D.H. Gjerstad. 1986. Effects of herbaceous weed control on a young loblolly pine plantation. Forest. Sci.32: 882–899.Google Scholar

Copyright information

© The New York Botanical Garden 1993

Authors and Affiliations

  • Randall W. Myster
    • 1
  1. 1.Terrestrial Ecology DivisionUniversity of Puerto RicoSan JuanUSA

Personalised recommendations