Summary of results from the Regional Forest Nutrition Research Project and Stand Management Cooperat...
Download
1 / 41

Nutrient Supply and Use - PowerPoint PPT Presentation


  • 80 Views
  • Uploaded on

Summary of results from the Regional Forest Nutrition Research Project and Stand Management Cooperative Rob Harrison, Dave Briggs, Eric Turnblom, Bob Gonyea, Bert Hasselberg. University of Washington. NUTSUPDM. Nutrient Supply and Use. POTENTIAL USE. SOIL SUPPLY. ACTUAL USE. REMOBILIZED.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Nutrient Supply and Use' - shania


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Summary of results from the Regional Forest Nutrition Research Project and Stand Management Cooperative

Rob Harrison, Dave Briggs, Eric Turnblom, Bob Gonyea, Bert Hasselberg.

University of Washington.


Nutrient supply and use

NUTSUPDM Research Project and Stand Management Cooperative

Nutrient Supply and Use

POTENTIAL USE

SOILSUPPLY

ACTUAL USE

REMOBILIZED

UPTAKE FROM SOIL


Results: Research Project and Stand Management Cooperative

Pre-RFNRP

1950’s through 1960’s


N200 Research Project and Stand Management Cooperative

N300

Percent volume response

N200-P88-S154

N200-P88-S168+

N100

N52-P12-K220

N rate (lb N/acre)


N+P Research Project and Stand Management Cooperative

N200-P88-S168+

N200-P88-S154

N100

N100

N300

N200

Percent volume response

N52-P12-K220

N52-P12-K220

N rate (lb N/acre)


N200-P88-S168+ Research Project and Stand Management Cooperative

N200-P88-S154

N100

N100

N300

N200

Percent volume response

N52-P12-K220

N52-P12-K220

N rate (lb N/acre)


Results of other studies Research Project and Stand Management Cooperative

Hodge-podge of nutrients other than nitrogen makes conclusions difficult. Several studies indicate results similar to the 2nd above, and many indicate the central role of N.

Clearly, both response to N and other nutrients is site controlled. Indicates need for larger scale studies on a wide variety of sites to pin response to site variables.


Conclusions of early studies Research Project and Stand Management Cooperative

“Nitrogen application evoked a growth response throughout a range of growing conditions. Magnitude of response is related to amount of nitrogen applied and response is still evident in 1975 from a 1962 application”.

“Apparent response to the application of other elements is quite variable and no consistent picture emerges. There is no evidence of an economic response to the other elements”.


RFNRP Research Project and Stand Management Cooperative

1969-pres.


Installations of the PNW Stand Research Project and Stand Management Cooperative

Management Cooperative


Rfnrp installations

RFNRP Installations Research Project and Stand Management Cooperative


Rfnrp installations1

RFNRP Installations Research Project and Stand Management Cooperative


Forest floor C/N ratio Research Project and Stand Management Cooperative


(1) Research Project and Stand Management Cooperative

Overall results of SMC studies Response vs. N rate. Sidell thesis.


Table 2. Research Project and Stand Management Cooperative Pilchuck Tree Farm study established 1994, measured through 2002 (8 y growth). Each treatment is replicated 6 times (two each installation).


Table 1. Research Project and Stand Management Cooperative Oregon Dept. Forestry study established 1995, measured through 1999 (4 y growth). Each treatment is replicated 6 times (two each installation).


Results of RFNRP studies Research Project and Stand Management Cooperative

N response averaging 20% (unthinned) -30% (thinned) with 400 kg N, highly site dependent.

Clearly, both response to N and other nutrients is site controlled. Indicates need for larger scale studies on a wide variety of sites to pin response to site variables.

Effects of N fertilization appear to be very long-lived.


SMC (1991+) Research Project and Stand Management Cooperative

No multi-element additions. SMC

Type II, III and IV no fertilizer work at all


  • SMC Type I Installations Research Project and Stand Management Cooperative

  • plantations with initial stocking 300-680 spa

  • Respace (PCT) before onset of competition

  • 7 core treatments (basic 7)

  • ISPHa, ISPHa/2, ISPHa/4,

  • ISPHa and ISPHa/2 min thin

  • ISPHa repeated thin

  • ISPHa heavy thin

  • 2-8 plots for other work, including fertilization

  • Eric Sucre did his M.S. on 7 fertilized sites


Location of SMC Type 1 Fertilized Research Installations Research Project and Stand Management Cooperative


Site descriptives
Site Descriptives Research Project and Stand Management Cooperative


Soil site properties examined
Soil & Site Properties Examined Research Project and Stand Management Cooperative

  • Climatic data

  • Elevation

  • % Slope

  • Relative Density (RD)

  • Quadratic Mean Diameter (QMD)

  • Site Index (SI)

  • bulk density (Db)

  • pH

  • C:N ratio

  • cation exchange capacity (CEC)*

  • Inorganic nitrogen (NO3- and NH4+)*

    *Mineral Soil only


Total volume and 4-year PAI relative response for each treatment regime at the respected treatment intervals (224 kg ha-1 of N as urea every 4 years). Standard errors are shown.


Multiple regression equations for the relationships between the unstandardized residuals of total volume (m3 ha-1) and 4-year PAI (m3 ha-1 yr-1) response to 224 kg N ha-1 as urea (dependent variables) and various soil, site and stand variables (independent variables).


Results of SMC studies the unstandardized residuals of total volume (m

too few sites (7) for broad generalizations

Response to N is site and stand controlled. Indicates need to couple fertilization with other silvicultural treatments, particularly stocking, and use RD or other stand properties to drive time of fertilization.


ad