Skip to main content

Competitive Effects of Various Grasses and Forbs on Ponderosa Pine Seedlings

Buy Article:

$29.50 plus tax (Refund Policy)


Competition between ponderosa pine seedlings and various grasses and forbs was studied on a site in northern Arizona burned in 1982 by a wildfire. Two-year-old pine seedlings were planted in 3.05 x 3.05 m plots in April 1983, followed by the sowing of grass and forb seeds on the same plots in July 1983 after summer rains had begun. Predawn xylem water potential of the pine seedlings was measured biweekly throughout the 1983 and 1984 growing seasons. Extractable soil nitrogen was measured at the beginning and end of both growing seasons. After the wildfire, nitrate and ammonium levels were significantly higher in the burned area than in an adjacent unburned area. Nitrate and ammonium concentrations in various grass treatment plots were significantly (P < 0.05) different at both the beginning and end of the growing season. Pine seedling xylem water potential differed among treatments, with potentials being lowest on plots sown with Agropyron desertorum. The differences in seedling xylem water potential and available soil nitrogen were reflected in differences in pine seedling growth. The most effective competitors were Agropyron desertorum and Dactylis glomerata. Results indicated that competition occurred for both moisture and available nitrogen. For. Sci. 33(2):356-366.

Keywords: Competition; Pinus ponderosa; ammonium; nitrate; xylem water potential

Document Type: Journal Article

Affiliations: College of Forest Resources, Department of Forest Biology, 217 Nutting Hall, University of Maine, Orono, Maine 04469-0125

Publication date: June 1, 1987

More about this publication?
  • Forest Science is a peer-reviewed journal publishing fundamental and applied research that explores all aspects of natural and social sciences as they apply to the function and management of the forested ecosystems of the world. Topics include silviculture, forest management, biometrics, economics, entomology & pathology, fire & fuels management, forest ecology, genetics & tree improvement, geospatial technologies, harvesting & utilization, landscape ecology, operations research, forest policy, physiology, recreation, social sciences, soils & hydrology, and wildlife management.
    Forest Science is published bimonthly in February, April, June, August, October, and December.

    2015 Impact Factor: 1.702
    Ranking: 16 of 66 in forestry

    Also published by SAF:
    Journal of Forestry
    Other SAF Publications
  • Submit a Paper
  • Membership Information
  • Author Guidelines
  • Ingenta Connect is not responsible for the content or availability of external websites

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Partial Open Access Content
Partial Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more