Statistics of ash dieback in Latvia

• Published in: Silva fennica (Helsinki, Finland : 1967) Vol. 52; no. 1
• Main Authors: Matisone, Ilze, Matisons, Roberts, Laiviņš, Māris, Gaitnieks, Tālis
• Format: Journal Article
• Language: English
• Published: Finnish Society of Forest Science 2018
• ISSN: 2242-4075; 2242-4075
• DOI: 10.14214/sf.9901

Dieback of the common ash ( L.) has been spreading throughout Europe since the 1990s, causing severe ecological and economical consequences; however, detailed statistics on its dynamics have been published rarely. This paper presents the dynamics of mature ash-dominated stands in Latvia for the period 2005â2015. Data from the national forest inventory and a permanent sampling plot network were summarised. According to the official statistics, the dieback has caused a twofold decrease in area of the ash stands (from 21â891 to 13â011 ha, which respectively comprised ca. 0.8 to ca. 0.4% of the total forest area). The official statistics on standing volume appeared biased, as they did not account for increased mortality. According to the permanent sampling plots, standing volume and stand density have been affected even more, having decreased by 53.1 and 69.9%, respectively, compared to 2005 (the stand density and standing volume of ash in 2015 was 77 individuals ha and 151 m ha, respectively). The mortality of the trees has not been stable. Stand density decreased faster during 2005â2009 compared to 2010â2015, with mortality rates of 9.6 and 8.2% year, respectively. In contrast, the decrease in standing volume in 2005â2009 was slower than in 2010â2015 (mortality rates were 4.7 and 7.7% year, respectively) because trees with smaller dimensions were more susceptible to the dieback. Nevertheless, the observed mortality rates clearly indicate negative prospects for ash stands in Latvia.Fraxinus excelsiorâ13â1â1â1