Laboratory of School of Forest Sciences

Laboratory equipment and analyses are continuously being developed as a part of the School’s quality system. Our aim to provide our customers with technically sound and reliable results according to ISO/IEC 17025 standards. All the laboratory staff members are committed to excellence in execution, monitoring and development of the laboratory services. Our staff takes full responsibility of the samples after they arrived in the laboratory. Laboratory is not responsible for taking the samples or quality of the sample taking process.

In order to ensure the best possible quality of your samples, you should always follow the given instructions on how to take samples. Good quality samples are the basis for reliable analyses and results and poor samples may jeopardize your research. Our laboratory staff is willing to guide you and answer to your questions. Equipment for plant and soil samples, such as secateurs and augers, as well as tree measuring equipment can be found in storage room 119.

Plan ahead

Find out what analyses you want to be taken and where -> take enough samples (g or ml).
Store the samples adequately before pretreatment (in room temperature, in fridge or in freezer).
Pretreatment of samples (drying, grinding, sieving, etc.).
Storage of samples after pre-treatment.

Sampling tools

Use the right kind of and clean tools e.g. stainless steel. Do not use rusty, painted or galvanised equipment. Clean the equipment always prior to taking samples. Use clean cloth, ethanol or water depending in the sample.

Sample taking

For element analyses -> dry sample 10g.
If you need additional analyses such as pH, conductivity, dry mass, ash content -> dry sample 50g or 50ml.
Store dry samples in paper sachets or bags and wet samples in a plastic bags or plastic jars.
When you bring samples from outdoors, dry them in +45C (sample bags open) or put them in a fridge or freezer.

Marking the samples

Make a sample list in Excel with running numbering. Laboratory will use the same running numbering for preparing the analyses. Mark the sample sachets/bags/jars with running numbering clearly with permanent marker (water resistant).

May you have any questions regarding samples, please ask the laboratory staff!

Pre-treatment and storing of samples have great effect on the final results of the analyses. In order to receive reliable results, you take care in pre-treating and storing your samples. For more detailed information, please see laboratory analyses or ask our laboratory personnel.

School of Forest Sciences has a separate dying room for samples, BOR 164. Sample pre-treatment, such as sieving, can be done in pre-treatment room BOR 160 where you will also find other necessary pre-treatment equipment. Grinding rooms with equipment are BOR 169 and 170.

Paper and plastic bags and other supplies for storing samples can be found in equipment room BOR  277B. Dry samples can be stored in BOR 165, cool rooms can be found in BOR 168, 210, 258 and 279. Freezers are in BOR168A, 224, 258A and 279A. Deep freezer (-80 °C) is located in BOR 296.

Storage

• Frozen  -20 °C or -80 °C
• Dried in room temperature

Pretreatment

• Drying in 40 °C and grinding
• More detailed instructions for pretreatment according to customer's needs

Chemical analyses

Element analysis following acid extraction treatment:

• Microwave wet combustion in HNO3-H2O2
• Suspension analysis by plasma emission spectrometer (ICP-OES). Elements that will be analysed: Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, S, Se, Zn, Ti. 
• CN (Variomax Cube)

Organic compound analyses

• Gas chromatography (GC)
• Spectrophotometry

Physiological analyses

• Frost-hardiness analysis by impedance equipment
• Water potential analysis by pressure chamber equipment

Storing

• Frozen  -20 °C 
• Dried in room temperature

Pretreatment

• Drying in 40 °C
• Air-drying in room temperature, well aerated space
• Roots will be removed from dried humus samples and samples will be grinded
• Dried mineral soil samples will be sieved

Physiological analyses

• Conductivity
• Soil water absorption by pressure disc equipment

Chemical analyses

• pH analysis from water suspension, wet or dry sample 1:2
• pH analysis from saline suspension (0.1M KCl tai 0.01 M CaCl2)

• Ignition loss at 550 °C, organic matter in percentage

  Element assay by acid treatment:

• Microwave wet combustion in HNO3-H2O2
• Suspension analysis by a plasma emission spectrometer (ICP-OES). Elements that can be analysed: Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, S, Se, Zn, Ti

• CN elements from a dry sample (Variomax Cube)

ITRAX X-ray analyses: tree ring density profile from which it will be possible to analyse average density, spring wood density, summer wood density and minimum and maximum density for tree rings: tree ring width, spring wood width and summer wood width. Ultrathin tree rings (width a lot under 1 mm) may be problematic for the analyses.

Pretreatment

• Wood discs that are sawn from wood core to surface as 3-5 cm in thickness, can be further processed with precision saw into 5 x 5 mm pieces for X-ray analyses. Sample moisture content will be standardised in a climate chamber (at least for two weeks in 12% humidity) before the X-ray analyses. 
• Fiber Tester -analyser: average fibre length and width; fibre form factor and length mass; and fibre length and width distributions in desired ranges such as 0.2-0.5-1 etc. 

Specimen

• Wood disc, or a part of it, from which tree ring samples can be removed for fibre analyses (for example 1-2 tree rings to ensure sufficient sample).