Figure 8. A group of Italian alders (Alnus cordata), some of which have
been infected by Phytophthora alni and subsequently died. This group was
planted on the College's nine-hole golf course in the 1980s, but since this
pathogen has become common in the area, this group of thirteen trees
has been reduced to just nine, with two standing dead and another three
with the symptoms of black bleeding on their trunks at the time I took the
second image. My TOT project is picking up much of the life cycle of trees,
from initial growth, flowering and fruiting, to major issues for trees as they
mature. I have quite a lot of instances where trees have died; sometimes you
only get an image of the tree beforehand, and an image of the empty space
afterwards, which has some impact on the students' learning, but it is better
where the intermediate stages can be shown.
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