USING TREES AGAINST GORSE

Press, Volume CIV, Issue 30745, 8 May 1965, Page 10

USING TREES AGAINST GORSE

The Mid-Canterbury Farm Forestry Association held a field day in the Darfield-Coalgate area last week—this was the first of two days to be devoted by the association to consideration of the best methods of using trees to smother gorse and broom. The second day will be held later this month at Kinloch, Little River.

Writing about the field day, the secretary of the association, Mr R. R. Beauchamp, says that “with the constantly rising value of land and the steady increase of population we cannot afford, as a nation or as individual farmers, to neglect the spread of gorse and broom. Both the foothills and the peninsula are places where soil, climate and rainfall encourage these noxious weeds. Good farmers have always used trees to reclaim dark faces and awkward gullies where gorse has become established. Unfortunately not all farmers are able and willing to put in the capital, time and labour needed for gorse control. Generally speaking this menace is increasing, particularly on hill country. “The Government policy of encouraging farmers to grow at least half of our future timber requirements, with loan money on easy terms available for this, makes it possible to attack the problem with renewed vigour. “The object of these two field days will be to have a look at what is being done now, and assess the value and cost of different methods of preparing, planting and tending. “The first operation that has to be tackled is to reduce the

gorse cover to a state where the trees can be planted. It is now generally considered that the cost of line cutting on country too steep for machines is prohibitive. This leaves us with spraying or burning—or a combination of both.

"Ideal planting conditions can be got by summer spraying followed by burning in the autumn —the trees being planted on the burn and a follow-up spray applied after one or two years. It is now well established that suitable sprays will knock the gorse back without harming the trees. Different “Members pointed out that every patch of gorse had a different set of problems—whether burning was safe and fire-breaks possible, whether soil and aspect made establishment easy or doubtful, and always the hazard of weather in the first year, times of planting and best size of tree stocks. In all these matters the farmer must use his own judgment, based on his own knowledge of his land and his previous experience with trees. It is, however, safe to say that early planting after an autumn burn, using 18-months stock, will provide the best conditions for a successful strike. “Three examples of gorse control planting on the foothills behind the HomebushCoalgate road were inspected. In every case a good, but not 100 per cent, cover of trees had been established, and in time the gorse would be suppressed. But with the trees now aged five to 12 years

pruning was called for if the full value of the stand as timber was to be the final objective. The trees were well above the gorse but generally for lack of a spray after planting the growth was so heavy it would take a man all his time to get into the stand. It is hard enough to get labour to prune a clean stand, but asking men to battle through dense undergrowth to get from tree to tree—well, it is going to cost a great deal more.

“The general impression about these examples was that the primary object of gorse suppression was achieved, but the secondary object, the production of a stand of high quality timber was still in doubt. As one of the blocks is the property of an enterprising . timber company, which is looking for supplies of good clean logs, the correct answer to this problem is important. “In two of the stands fire was a very real hazard. The bottom boundary was a road. The trees had been planted up to the owner’s fence, leaving half a chain of heavy gorse coming right to the road and providing a perfect target for the casual match or cigarette butt. It was considered that in future planting an essential preliminary would be to clear the roadside, thus carrying out the owner’s legal obligation and providing a fire-break. The planting of moist gullies with poplars at 15 by 15 spacings makes a useful fire-break. “The field day was worthwhile if only because it opened up some of the problems of planting trees to control gorse. It was generally agreed that any suggestions and recommendations should be reserved until after the next field day,” said Mr Beauchamp.