Tapio Linkosalo. (1999). Regularities and patterns in the spring phenology of some boreal trees. Silva Fennica vol. 33 no. 4 article id 647. https://doi.org/10.14214/sf.647

Keywords: Populus tremula; Pinus sylvestris; flowering; Alnus glutinosa; bud burst; Alnus incana; phenological regulation; phenological time series; Betula sp.

Abstract | View details | Full text in PDF | Author Info

Phenological time series of flowering and bud burst of Populus tremula (L.) and Betula sp., and the flowering of Pinus sylvestris (L.), Alnus glutinosa (L.) and Alnus incana (L.) were constructed from data collected in Finland during the period 1896–1955. The resulting combined time series were examined with two aims in mind: first, to determine the phenological regularities between different species and, second, to detect patterns of spring advancement over a geographically large area. The results indicate that the geographical pattern of spring advancement is rather uniform from year to year, and between different species. Furthermore, the mechanisms regulating the timing of phenological events in different species seem to function in a similar way, suggesting an unanimous optimal response to climatic conditions.

Linkosalo, University of Helsinki, Department of Forest Ecology, Unioninkatu 40 B, P.O. Box 24, FIN-00014 University of Helsinki, Finland E-mail: tapio.linkosalo@helsinki.fi

Category : Research note

article id 91, category Research note

Raisa Mäkipää, Tapio Linkosalo. (2011). A non-destructive field method for measuring wood density of decaying logs. Silva Fennica vol. 45 no. 5 article id 91. https://doi.org/10.14214/sf.91

Keywords: coarse woody debris; carbon stock; decaying wood; wood decomposition; penetrometer; pilodyn

Abstract | View details | Full text in PDF | Author Info

Decaying dead wood density measurements are a useful indicator for multiple purposes, such as for estimating the amount of carbon in dead wood and making predictions of potential diversity of dead wood inhabiting fungi and insects. Currently, qualitative decay phases are used as wood density estimates in many applications, since measuring the density is laborious. A quantitative measure of density would, however, be preferred over the qualitative one. Penetrometers, which are commonly used for measuring the density of standing trees, might also be applicable to dead wood density measurements. We tested the device for making quick, quantitative measurements of decaying logs. The penetrometer measures the depth into which a pre-loaded spring forces a pin in the wood. We tested pins of 5 and 10 mm diameter together with an original 2.5 mm pin and compared the results with gravimetric density measurements of the sample logs. Our results suggest that the standard pin works for less decayed wood, but for more decomposed wood, the thicker 5 mm pin gave more reliable estimates when the penetration measures were converted to densities with a linear regression function (R² = 0.62, F = 82.9, p = 0.000). The range of wood densities successfully measured with the 5 mm pin was from 180 to 510 kg m^–3. With the 10 mm pin, the measuring resolution of denser wood was compromised, while the improvement at the other end of density scale was not large. As a conclusion, the penetrometer seems to be a promising tool for quick density testing of decaying logs in field, but it needs to be modified to use a thicker measuring pin than the standard 2.5 mm pin.

Mäkipää, The Finnish Forest Research Institute, Vantaa, Finland E-mail: raisa.makipaa@metla.fi
Linkosalo, The Finnish Forest Research Institute, Vantaa, Finland E-mail: ts@nn.fi

Click this link to register to Silva Fennica.

If you are a registered user, log in to save your selected articles for later access.

Contents alert

Your selected articles
Send to email

Päivänen J., (1973) Hydraulic conductivity and water retention in pe.. Acta Forestalia Fennica vol. 0 no. 129 article id 7563 (remove) | Edit comment

Suominen O., (1963) Susceptibility of stands to devastation by snow... Silva Fennica vol. no. 112 article id 4707 (remove) | Edit comment

Reitala A., (1987) Forests in Finnish art Silva Fennica vol. 21 no. 4 article id 5334 (remove) | Edit comment

Finnish Society of Forest Science ., (1967) Forestry research in Finland and its further dev.. Silva Fennica vol. 1 no. 4 article id 4757 (remove) | Edit comment

Heikkilä T., (1929) The interest rate of forest Acta Forestalia Fennica vol. 34 no. 7 article id 7220 (remove) | Edit comment

Maliniemi E., (1954) Statistical analysis on felling and haulage of s.. Silva Fennica vol. no. 82 article id 4642 (remove) | Edit comment

Keränen J., (1954) Heating season and factors affecting temperature.. Acta Forestalia Fennica vol. 62 no. 1 article id 7450 (remove) | Edit comment

Peura M., Triviño M. et al. (2016) Managing boreal forests for the simultaneous pro.. Silva Fennica vol. 50 no. 5 article id 1672 (remove) | Edit comment

Heikinheimo O., (1934) Research on forest regeneration methods Acta Forestalia Fennica vol. 40 no. 23 article id 7300 (remove) | Edit comment

Ahnlund Ulvcrona K., Karlsson L. et al. (2013) Comparison of silvicultural regimes of lodgepole.. Silva Fennica vol. 47 no. 3 article id 974 (remove) | Edit comment

Puttonen P., (1988) Presentation report of evaluation group on fores.. Silva Fennica vol. 22 no. 4 article id 5365 (remove) | Edit comment

Finnish Society of Forest Science ., (1946) Publications of the Society of Forestry in Finla.. Silva Fennica vol. no. 62 article id 4582 (remove) | Edit comment

Westman C. J., Laine J. et al. (1985) A comparison of gravimetric and volumetric soil .. Silva Fennica vol. 19 no. 1 article id 5232 (remove) | Edit comment

Aalto T., Hari P. et al. (2002) Comparison of an optimal stomatal regulation mod.. Silva Fennica vol. 36 no. 3 article id 529 (remove) | Edit comment

Lafleur B., Fenton N. J. et al. (2010) Contrasting effects of season and method of harv.. Silva Fennica vol. 44 no. 5 article id 122 (remove) | Edit comment

Oleksyn J., Tjoelker M. G. et al. (1998) Adaptation to changing environment in Scots pine.. Silva Fennica vol. 32 no. 2 article id 691 (remove) | Edit comment

Niemistö P., (2013) Effect of growing density on biomass and stem vo.. Silva Fennica vol. 47 no. 4 article id 1002 (remove) | Edit comment

Malinen J., (2003) Locally adaptable non-parametric methods for est.. Silva Fennica vol. 37 no. 1 article id 514 (remove) | Edit comment

Eliasson L., (2005) Effects of forwarder tyre pressure on rut format.. Silva Fennica vol. 39 no. 4 article id 366 (remove) | Edit comment

Sironen S., Kangas A. et al. (2001) Estimating individual tree growth with the k-nea.. Silva Fennica vol. 35 no. 4 article id 580 (remove) | Edit comment

Cajander A. K., (1927) The scientific foundation of forestry as exempli.. Silva Fennica vol. no. 4 article id 4445 (remove) | Edit comment

Hantula J., Vainio E. (2003) Specific primers for the differentiation of Hete.. Silva Fennica vol. 37 no. 2 article id 500 (remove) | Edit comment

Lindroos O., Henningsson M. et al. (2010) Forces required to vertically uproot tree stumps Silva Fennica vol. 44 no. 4 article id 135 (remove) | Edit comment

Malmivaara M., Löfström I. et al. (2002) Anthropogenic effects on understorey vegetation .. Silva Fennica vol. 36 no. 1 article id 568 (remove) | Edit comment

Follow @SilvaFennica