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The Rural Voice, 2003-01, Page 670 years of study shows diameter cutting detrimental I wish to correct some misinformation propagated by the group of loggers and sawmill operators who wrote (in the December 2002 issue) in response to the October 2002 article "Spare the Axe". The studies that show diameter - limit cutting is detrimental to long term forest productivity were not done by the Maitland Watershed Partnerships. They have been conducted over the last 70 years or more in carefully controlled experiments. Eyre and Zillgitt published a pioneer article on the subject in 1953. after 20 years of research. Further studies have only reinforced the earlier findings. The results are clearly summarized in the Silvicultural Guide for Southern Ontario (2001), the standard for forest management. What these studies show is that the best timber growth is achieved when a hectare of forest is occupied by trees of mixed sizes and where trees greater that 25 cm diameter at breast height occupy about 20 square metres. Measurement of the area occupied by standing trees is referred to as basal area. If the basal area is too low overall timber growth is limited because the space is under-utilized (analogous to planting crops too thinly). Individual trees may have rapid diameter growth, but timber quality is compromised because of excessive branching. There may also be dieback because of exposure. If the basal area is too high, competition and mortality limit stand growth. The Silvicultural Guide 2 THE RURAL VOICE Feedback recommends that. if timber production and quality re to be maximized, after cutting, the remaining basal area of trees over 25 cm diameter should be about 15 square metres per hectare. What the Maitland Watershed Partnerships study showed was that in a sample of 100 forest stands where basal area was measured. 77 per cent of forests had basal areas lower than this optimal value, sometimes much lower. A similar study in Middlesex County in 2001 told the same story. According to the "ideal" size class distribution, providing the best growth, forest in the Maitland watershed also had overstocking of smaller trees, meaning that they ale competing with one another and will have below -optimal growth. Both these findings — too few larger trees and too many small trees — are a direct result of diameter -limit cutting. Few professional foresters would advocate diameter -limit cutting as good forestry practice. Contrary. to the arguments put forward in the "logger response", all the evidence suggests that repeated diameter -limit cutting degrades both timber volume and timber quality. Certainly at a single cut the harvest volume may be higher and the cash returns greater, but it is like cashing in capital instead of living on investment income. One of the main reasons that diameter limit harvesting has been so widely used, and is written into so many by-laws, is that it is simpler to understand and easier to enforce than basal -area -based methods. This should not be mistaken for good forest management.0 – Jane Bowles PhD Ecologist Thorndale UPI promotes ethanol -blended gas too I just received the December issue of The Rural Voice and would like to comment on some information in the news report of Steve Peters' speech to the Bruce County Federation of Agriculture. In the article, Peters mentions that the Liberal party is encouraging people to use "green fuels" and that the only major oil company to blend ethanol is Sunoco. This is true, however, I would like to point out there are other retailers of ethanol - blended gasolines. Take for instance the organization I work for – UPI Inc. UPI is the only retailer to both farms and motorists of ethanol - blended gasolines with province -wide coverage and we have been doing so since the early '90s. We do retail Sunoco fuel but I would hate for your readers to interpret from the article that they could only fuel up with environmentally -friendlier fuel from Sunoco gas bars. UPI Inc. is the energy supplier of choice to Ontario's Agricultural Member Co-operatives and we also retail directly to rural consumers across Ontario. Our organization supports Ontario's farmers by retailing ethanol -blended gasolines, which contain fuel ethanol made from Ontario -grown corn. As a rural publication, I would have hoped that a rural company, such as UPI Inc. would have been mentioned in your article since we are renowned for retailing environmentally -friendlier fuels. UPI is also the first energy supplier in Canada to utilize modern, cost- effective, above -ground storage and dispensing technology in the construction of a retail gasoline outlet. We are constructing above- ground gas bars which means the fuel storage is located above ground. As a result, it is an environmentally - friendlier concept in gas bars and reduces the risk of contaminating nearby agricultural heartlands. In fact, UPI was just awarded, through nationwide ballots, the Canadian Renewable Fuels Association prestigious award in recognition of UPI's continued leadership and commitment to the development of the Renewable fuels Industry in Canada.0 – Debbie Berg Manager, Public Relations & Customer Care UPI Inc.