Wednesday 31 December 2008

Pine mystery update

After examining dozens of needles very closely, I stumbled across the following specimen which shows a brown needle with an intact green area at the tip.



Even closer examination shows that the brown areas of the needle are in fact hollow, and the needles have been eaten from the inside, thereby killing them. This is indicative of micromoth leaf-miners, and research shows that there are perhaps 8 to 10 candidate species of micromoth which eat Pine needles in this manner. What I need to do next year is to take needle samples with occupant larvae and breed them through to the adult stage for identification.

And yes, the adult micromoths are, indeed, tiny.

So that's it for 2008, the year with the worst weather I can remember. Still, I don't feel too bad: I managed 89 posts, which is roughly one every 4 days. In addition, I was talking to a local gentleman of 87 years, who said it's the worst year for weather in his memory, too.

Monday 22 December 2008

Scots Pine mystery

In one particular part of the young coniferous plantation, Scots Pine trees are growing in a peculiar manner. This is a shot of an affected tree:

Note the 'pom pom' effect on the branches.

Here's a close-up of an affected shoot:

The damage appears to be caused by clusters of needles dying and dropping off:


This shot shows that multiple areas of single plants are simultaneously affected:

I was told that the effect can be caused by the European Pine Sawfly, but my research shows that this sawfly damages needles in a completely different way: by eating them down to the branch. So it looks like I'm back to square one on this one.