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Inside View: January 2008

January 30, 2008  By Gary Jones

Connecting salmon, beetles and veggies?  And I am not advocating one system over another, on this evidence alone, at least.

Monday, Sept. 17th, of 2007, was an ‘interesting’ day for agriculture in British Columbia. Two separate reports were published on different agricultural topics. One stated that scientists have ‘proven’ beyond all reasonable doubt that sea lice from farmed salmon pens are lethal to wild salmon around the Pacific coast of the province.

The second was published by the B.C. Ministry of Forests, and it reported that the Mountain Pine Beetle (Dendroctonus ponderosae) will have killed 40 per cent of British Columbia’s pine forest by the end of the year.


Moving south from the central interior to the southern half of the province, some 130,000 square kilometres of forestlands are now either red (under attack from the beetle) or dead. So, “what’s the connection between the fish and the trees, and more importantly with my greenhouse?” I hear you ask. Bear with me a little longer.

Earlier this year, I joined the B.C. Institute of Agrologists at their AGM, held this year in Prince George, northern B.C. Standing atop a snow-covered hill, we viewed mile upon mile of infested Lodgepole pine (Pinus contorta).
The effects of the beetle in B.C. have been several fold:

• Obviously, a reduction in the amount of trees, leading to increased water runoff and subsequent localized soil erosion.

• Reduced areas of pasture for range grazing of cattle.

• Effects on fish populations.

• An increase in invasive weeds in beetle affected areas.

• Now, some of the cause(s) of increased beetle populations are due to natural effects like the milder winters experienced in recent years. And some of the causes are clearly man-made, such as the improvements in fire retardants for forest fires that have provided a more favoured habitat in which beetles can multiply.

The connection between the salmon story and that of the Pine beetle is that they are both typical of intensive monoculture farming systems. The warnings are obvious for other such systems. OK, so the organic lobbyists have been telling us this for years. Please, some of us are just slower learners. At the turn of the year, Kwantlen began its first organic greenhouse vegetable course. Students set up some raised beds using several organic growing media in a poly house, and planted the beds up with a range of typical greenhouse veggies (tomatoes, cucumbers, peppers, eggplant and lettuce) and also sowed green manures (cover crops) onto those beds. At the same time, students in Kwantlen’s other production classes grew the normal ‘monocrops’ of those same species hydroponically in greenhouses. All well and good.

During the summer, however, labour at the school is spread more thinly (there are no students!). Crop growth in both situations slowly outpaced work rates, and pests invaded several crops. The hydroponic houses, although being provided with biological controls on a regular basis, succumbed to spider mites and aphids in a fairly major way, and isolated pesticide applications were necessary. However, the ‘organic’ (non-certified) poly house was pretty much left to ‘figure it out for itself.’ Curiously, it did seem to ‘figure it out,’ and although the crop looked a little untidy compared to ‘conventional greenhouses,’ the pest populations in that house seemed to be considerably less damaging.

Now, of course, it’s impossible to say from this that ‘conventional’ (hydroponic) is not as good as (almost) organic, or vice versa. Nor am I trying to say that is the case anyway. “It may have been coincidence,” you say. Of course, it may have been. And I am not advocating one system over another, on this evidence alone, at least. All I will say is that the difference in pest damage was quite startling. Maybe mono-crop “massification” (Mander, in Kimbrell’s text, The Fatal Harvest Reader,2002) is not the right way to keep going. The Food and Agriculture Organization reported that “75 per cent of genetic diversity in agriculture was lost this century” (Mander again). Maybe it’s time, if not too late already, to stop our ‘Newtonian thinking’ (Suzuki, The Sacred Balance, 1997) and catch up with our sustainable colleagues. Perhaps there is a connection after all between salmon, pine beetle and those juicy tomatoes you’re eating.

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