Cybis Forums

Hi,

I'm starting here at the very beginning of dendrochronology, but wish to eventually create a 5-600 year old (minimum) English Oak reference curve that is scientifically valid.

So, at the very beginning I shall start...boring holes into living trees, as advised! I have emailed Haglöf for advise and prices on their increment borers for large oaks. There are more oaks in Bath (where I live) in excess of 2.5mtr diameter than I can count, so feel these to be invaluable sources of data if I can get at it...they do sell 1000mm borers (would they most likely get jammed at those depths in an old oak?).

Am I being too ambitious thinking I can access the inner most rings of these great trees with an increment borer? Has anybody any advice? How deep can you realistically bore into a living oak?

Many thanks for all the private emailing help I have had so far,

Best wishes,

Stuart (UK)

Sorry, I did mean to mention that my login may only be once or twice a week (such is the intensity of managing a young family...it's getting easier and more time is becoming available) so please be patient with me. Stuart

Hi,

I know there unfortunately have been a lot of trouble with coring living oaks. If you search the ITRDBfor for "Haglof" last four years or something you will see some of it... Maybe they have improved the quality - the told they were to - but I do not know if they have been successful yet (there have not been any discussions about that during the last year or so, as I can remember... so maybe it is better!). The problem is that living oaks are very hard and the friction is very high (also if using a lot of lubricant oil or probably better: bee wax). And with a long handle (as you get with a long corer - and also may need to turn it around) the power and pressure to the bit will be very high, and the material in the bit will probably crash too soon. Generous with wax, clean carefully between each core and do not core too fast in order to avoid to high temperatures according to friction, may help. But 1000 mm - it sounds really a bit too optimistic to me. I have cored some oaks with 400 mm borer, and already that is difficult.

But, as the tree will decrease the annual growth rate continously you will also find that the innermost part of the tree will not contain too many rings. So maybe it is better to (also) try with a shorter (and less expensive) corer?

If there are some older constructions of oak in your area, they too would be a very useful source. It is much easier to core dry oak wood than fresh! I have cored a lot of wind mill posts and other construction details at the island of Öland (south east Sweden), and it works fine. And than you do not need such a very long corer to get access to old rings either. (I am working with 250 mm and sometimes 400 mm for that purpose)

Best regards

/Torbjörn Axelson