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Fig. 1. Pycnidia of Sphaeropsis sapinea on (A) a Scots pine twig and (B) a needle. (C) Conidia of Diplodia sapinea released from a pycnidium (Ø 250 µm, modified from Schlößer 2020).

Table 1. Investigated Scots pine stands and number of collected samples.
Site No. Location Latitude, Longitude No. of
trees 		No. of branches No. of
tips 		Avg. age
of trees 		Sampling month Sampling height, m
1 Vantaa 60°25´N, 25°07´E 10 10 30 40 July 2
2 Mäntsälä 60°68´N, 25°19´E 1 1 3 20 July 10
3 Lohja 60°29´N, 23°55´E 10 10 30 20 July 2
4 Lapinjärvi 60°64´N, 26°15´E 6 6 18 60 July 10
5 Akaa 61°16´N, 23°90´E 11 11 33 40 July 2
6 Urjala 61°10´N, 23°52´E 4 4 12 40 July 2
7 Hyytiälä 61°80´N, 24°30´E 6 6 18 40 July 4
8 Route 66 61°80´N, 24°30´E 3 3 9 20 July 4
9 Setälänkangas 61°80´N, 24°20´E 3 3 9 20 July 2
10 Setälänkangas 61°80´N, 24°20´E 4 4 12 40 July 4
11 Siikakangas 61°90´N, 24°20´E 5 5 15 40 July 4
12 Skaftung 62°15´N, 21°33´E 8 8 24 40 August 2
13 Kivalo 66°00´N, 25°50´E 6 6 18 80 and 40 July several
14 Lapajärvi 66°70´N, 28°40´E 3 3 9 35 August 10
     SUM: 80 80 240      
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Fig. 2. Three examples of Sphaeropsis sapinea morphology on 1.5% MEA plate. The hyphae color can vary from light grey to intense black.

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Fig. 3. Locations of the investigated Scots pine sites in this study as dots. Reprinted and modified from Free Vector Maps. Red dots indicate sites where Sphaeropsis sapinea was found in this study; number one (Vantaa) and five (Akaa).

Table 2. Number and origin of Sphaeropsis sapinea isolates from healthy Scots pine shoots.
        No. of S. sapinea isolates in annual shoots of Scots pine
No. of site Location No. of trees infected Age of trees 2019 2018 2017
1 Vantaa 2 40 5 4 3
5 Akaa 2 40 0 0 4
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Fig. 4. Example of mature Scots pine stand that died during growth season of 2019, due disease caused by Sphaeropsis sapinea. Scots pine trees were stressed due to high temperatures and drought during 2010 and 2018 that lead to Diplodia tip blight disease epidemic, Germany 2019 (A). Blue stain developes fast in dead trees that can be seen after felling, partly this blue stain is due to S. sapinea, Germany 2019 (B).