Six Hills Forest Partnership
Storms - Site Visit - Budget
20 November 2000
There has been some wind-throw or 'toppling' on AH1 and AH2 ('Ahuriri') from a severe SW storm on October 12. Fortunately it will not be very significant overall I believe, and your stands did not suffer anything like the large patches of devastation some other Port Hills and Peninsula stands did. This is because they are partly sheltered and have mixed aspects although predominantly south facing.
Generally the storm has caused an early minor (and free!) thinning over about 60% of the area. Over about 35% there is virtually no damage, and about 5% in small pockets is significantly damaged.
It was the wetness combined with the constant and prolonged high wind that caused it. The soil on the Peninsula is deep and loose so with enough rain, trees in some situations lose their footing.
What has to be remembered is that we planted at least 1000 trees/ha of which we need select only 300/ha as a final crop, by thinnings to be carried out at age 6 & 9. Accordingly I am still confident 90% of each site will have a full stocking of good trees. Another few inches of rain, a second day of storm and we could have been much more severely affected.
There was also some minor damage on LH2, GT7 and HF1 in North Canterbury from earlier westerly storms, but it really is of no significance. Your Douglas-fir on Glens of Tekoa (GT10) was unaffected, despite huge rain-storms there. That species is considerably more wind-firm.
Between age 2 & 5 there is a period Radiata plantations are vulnerable to toppling on deep loose soils. They do not form adequate root systems until a little older, about the time of the first thinning. Usually in the Canterbury foothills the soil structure is stronger and much freer draining so the risk of toppling may be lower despite more wind and rain. Conditioning comes into play too. There has also been very good growth for two years, so the 'sail-area' of radiata compared with its roots, added to its vulnerability.
Next year's Budget
Working on this at the moment, not that there is very much to it other than some suppression of broom on GT7 and LH2. More on this soon, but you're probably looking at about $200 per unit for 2001.
Very few of you have ever been out to your fine Douglas-fir stand on Glens of Tekoa, part of which is featured in the latest photo. So how about a trip there? It could be 11, 12, 18 or 19 December or any weekend day in February. All those interested please send me a message by phone, fax, e-mail or letter giving your availability. If there is sufficient interest I will organise a trip accordingly. Otherwise they'll be that much bigger next summer!
WARREN FORESTRY Ltd
Manager for the Partnership Committee