Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-24T02:23:45.199Z Has data issue: false hasContentIssue false
  • English
  • Français

Growth and Water Relations of Douglas Fir (Pseudotsuga menziesii) Seedlings under Different Weed Control Regimes

Published online by Cambridge University Press:  12 June 2017

Michael Newton  and
David S. Preest
Michael Newton
Affiliation:
For. Ecol., Oregon State Univ., Coll. of Forestry, Corvallis, OR 97331
David S. Preest
Affiliation:
New Zealand For. Serv., For. Res. Inst., Rotorua, N.Z.
Get access Rights & Permissions [Opens in a new window]

Abstract

Growth of Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] was increased by controlling grasses and broadleaf herbs with eight herbicide regimes during the first 3 yr after planting on a well-drained moist site in the Oregon Coast Range. The greatest growth occurred if weeds were controlled in the same growing season that tree seedlings were transplanted to the field; smaller increments came from second- and third-year weed control. Growth increases attributable to early weed control continued through the fifth year, indicating that conditions during establishment strongly influenced later growth. Plots with no herbaceous vegetation had more available soil water than those with competing vegetation, and tree seedlings on these plots experienced less water stress. Irrigation in the third year increased stem diameter of seedlings in that year but had no effect thereafter. Increases in average seedling stem volume at 5 yr after transplanting were linearly related (r2 = 0.77) to the difference in observed xylem potential during the first three growing seasons after transplanting and the xylem potential at which photosynthesis ceased, −2 MPa.

Keywords

Atrazineweed controlirrigationphenoxy herbicidesstomatal conductancewater potentialAGSTE
Type
Weed Control and Herbicide Technology
Information
Weed Science , Volume 36 , Issue 5 , September 1988 , pp. 653 - 662
Copyright
Copyright © 1988 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Benecke, U. 1980. Photosynthesis and transpiration of Pinus radiata Don under natural conditions in a forest stand. Oecologia 44:192–198.CrossRefGoogle Scholar
2. Brix, H. 1979. Effects of plant water stress on photosynthesis and survival of four conifers. Can. J. For. Res. 9:160–165.CrossRefGoogle Scholar
3. Cleary, B. D. and Zaerr, J. B. 1980. Pressure chamber techniques for monitoring and evaluating seedling water status. N.Z. J. For. Sci. 10:133–141.Google Scholar
4. Cole, E. C. and Newton, M. 1987. Fifth-year responses of Douglas-fir to crowding and non-coniferous competition. Can. J. For. Res. 17:181–186.CrossRefGoogle Scholar
5. Conard, S. G. and Radosevich, S. R. 1982. Growth responses of white fir to decreased shading and root competition by montane chaparral shrubs. For. Sci. 28:309–320.Google Scholar
6. Havranek, W. M. and Benecke, U. 1978. The influence of soil moisture on water potential, transpiration, and photosynthesis of conifer seedlings. Plant Soil 49:91–103.CrossRefGoogle Scholar
7. Hinckley, T. M., Austin, R. G., Aubuchon, R. R., Metcalf, C. L., and Roberts, J. E. 1978. Leaf conductance and photosynthesis in four species of the oak-hickory forest type. For. Sci. 24:73–84.Google Scholar
8. Hinckley, T. M., Lassoie, J. P., and Running, S. S. 1978. Temporal and spatial variations in the water status of forest trees. For. Sci. Monogr. 20. 72 pp.Google Scholar
9. Meinzer, F. C. 1982. The effect of vapor pressure on stomatal control of gas exchange in Dougls-fir saplings. Oecologia 54:236–242.CrossRefGoogle ScholarPubMed
10. Murphy, E. M. and Ferrell, W. K. 1982. Diurnal and seasonal changes in leaf conductance, xylem water potential and abscisic acid of Douglas-fir in five habitat types. For. Sci. 28:627–638.Google Scholar
11. Newton, M. 1964. Seedling survival and vegetative competition. Page 39–42 in Western Reforestation. West. For. and Conserv. Assoc., Portland, OR.Google Scholar
12. Newton, M. 1975. Forestry weed control progress. Proc. Oregon Weed Control Conf. 24:32–34.Google Scholar
13. Petersen, T. D. and Newton, M. 1985. Growth of Douglas-fir following control of snowbrush and herbaceous vegetation in Oregon. Down Earth 41(l):21–25.Google Scholar
14. Ritchie, J. T. 1973. Influence of soil water status and meteorological conditions on evaporation from a crop canopy. Agron. J. 65:893–897.CrossRefGoogle Scholar
15. Preest, D. S. 1977. Long-term growth response of Douglas-fir to weed control. New Zealand J. For. Sci. 73:329–332.Google Scholar
16. Running, S. W. 1976. Environmental control of leaf water conductance in conifers. Can. J. For. Res. 6:104–112.CrossRefGoogle Scholar
17. Waring, R. H. and Running, S. W. 1978. Sapwood water storage: its contribution to transpiration and effect upon water conductance through the stems of old-growth Douglas-fir. Plant Cell Environ. 1:131–140.CrossRefGoogle Scholar
18. Webb, W. L., Szarek, S., Lauenroth, W., Kinerson, R., and Smith, M. 1978. Primary productivity and water use in native forest, grassland, and desert ecosystems. Ecology 59.1239–1247.CrossRefGoogle Scholar