Heikki Hänninen, Jaana Luoranen, Risto Rikala, Heikki Smolander. (2009). Late termination of freezer storage increases the risk of autumn frost damage to Norway spruce seedlings. Silva Fennica vol. 43 no. 5 article id 175. https://doi.org/10.14214/sf.175

Keywords: Norway spruce; simulation; autumn frost damage; day degrees; freezer storage; growing season

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

Over the last few years it has become increasingly common in artificial forest regeneration to extend the planting period by using freezer-stored seedlings for early summer plantings. Developmentally, however, planted freezer-stored seedlings lag behind seedlings planted earlier in the spring. As freezer-stored seedlings also start hardening later, they are more susceptible to early autumn frosts, especially in years when the thermal growing season ends and the first autumn frosts come earlier than usual. By means of computer simulations with a simple temperature sum model and long-term air-temperature data from three locations in Finland, we examined the effect of the freezer-storage termination date on the risk of autumn frost damage to the seedlings. The long-term simulations revealed a drastic effect of year-to-year variation in the thermal conditions during the growing season on the occurrence of autumn frost damage. Such results provide crucial information complementary to those obtained in field experiments, which are always restricted to a relatively short time period. Together with earlier field data, the present results suggest that at an average regeneration site in central Finland, the planting of seedlings whose storage has terminated on 15 June and 22 June involve autumn frost damage every tenth and every fifth year, respectively. The sensitivity analysis revealed that the temperature sum requirement of maturation has a great effect on the risk of autumn frost damage, thus pinpointing the need for experimental studies addressing this ecophysiological trait of the seedlings.

Hänninen, Plant Ecophysiology and Climate Change Group (PECC), Department of Biological and Environmental Sciences, Box 65, FI-00014 University of Helsinki, Finland E-mail: heikki.hanninen@helsinki.fi
Luoranen, Finnish Forest Research Institute, Suonenjoki Research Unit, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: jl@nn.fi
Rikala, Finnish Forest Research Institute, Suonenjoki Research Unit, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: rr@nn.fi
Smolander, Finnish Forest Research Institute, Suonenjoki Research Unit, Juntintie 154, FI-77600 Suonenjoki, Finland E-mail: hs@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

Kankare V., Luoma V. et al. (2019) Assessing feasibility of the forest trafficabili.. Silva Fennica vol. 53 no. 3 article id 10197 (remove) | Edit comment

Kaunisto S., Sarjala T. (1997) Critical needle potassium concentrations indicat.. Silva Fennica vol. 31 no. 4 article id 5633 (remove) | Edit comment

Kilkki P., (1970) Book review: Beståndsvård och productionsekonomi Silva Fennica vol. 4 no. 3 article id 4827 (remove) | Edit comment

Cajander A. K., (1934) Suomen metsätieteellisen tutkimustyön kehittämin.. Acta Forestalia Fennica vol. 40 no. 2 article id 7279 (remove) | Edit comment

Järveläinen V.-P., (1993) Private forestry and the changing values Silva Fennica vol. 27 no. 3 article id 5516 (remove) | Edit comment

Follow @SilvaFennica