U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Application Technology Research: Wooster, OH
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                                    Software
                People

                    Staff Listing
                                    Careers


        


                    Departments
                        Agricultural Engineering
                                    Entomology
                                    Horticulture
                                    Plant Pathology
                                    IR-4 programSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Midwest Area Wooster, Ohio Application Technology Research Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Altland, Jamesitem
                                            MIELCAREK, MARTA - OREGON STATE UNIV.item
                                            OWEN, JAMES - OREGON STATE UNIV.item
                                            ZAZIRSKA, MAQDALENA - OREGON STATE UNIV.
  Submitted to: Southern Nursery Association Proceedings
                                    Publication Type: Abstract Only
                                    Publication Acceptance Date: 8/1/2007
                                    Publication  Date: 11/1/2007
                                    Citation: Altland, J.E., Mielcarek, M., Owen, J., Zazirska, M. 2007. Continuous columns for determining moisture characteristic curves of soilless substrates. Southern Nursery Association Proceedings. 52:538-542.Interpretive Summary:
                                Technical Abstract: Sound water management is essential for effectively producing nursery crops.  Understanding substrate water availability is a critical component to managing irrigation properly.  The objective of this paper is to report a method for generating moisture characteristic curves of soilless substrate that is quick, inexpensive, and offers greater precision at low tensions. 
Douglas fir (Pseudotsuga menziesii) bark (DFB) [screened to 0.9 cm (0.4 in)] was collected from stockpiles intended for nursery container production (Marr Bros. Monmouth, Ore.).  Unscreened pumice (<0.95 cm (0.38 in), Pro-Gro, Sherwood, OR) and Canadian sphagnum peat (Sun Gro Horticulture Canada Ltd., LAVAL, Quebec) were used to make three substrates including: 1) 70:30-DFB:pumice (by vol.); 2) 70:30 DFB:peat (by vol.); and 3) DFB (not amended).  Substrates were adjusted to 1.5 g·g-1 mass wetness.  The DFB substrate was used to generate moisture characteristic curves over multiple dates to ensure the procedure was reliably repeatable.   The 70:30-DFB:pumice and 70:30-DFB:peat substrates were used to determine if our method was able to differentiate between substrates of presumably different water holding capacities.  
Moisture characteristic curves for DFB (not amended) were estimated on three dates.  The lack of fit test indicated that lines were similar, demonstrating this procedure provides consistent results over time when analyzing a similar substrate.  The procedure took one week each time it was performed (including: saturating, draining, freezing, and drying).  This is a much shorter period of time than is required for other procedures that use some sort of applied pressure apparatus (4 to 6 weeks). 
The addition of peat increased the amount of easily available water from just 2% up to 16% and decreased water buffering capacity from 6% to 2% when compared to DFB substrate.  With pumice (70:30-DFB:pumice), easily available water increased from 2% to 5% while water buffering capacity dropped from 6% to 1% when compared to non-amended DFB substrate.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov