Experts seem to agree on one basic requirement for farm sustainability: every farm should have a sizeable proportion of its land under trees and shrubs. The consensus seems to be that this proportion should be around 35 per cent. Several independent studies have come up with a figure in that order. Which leads to the next question: what species of trees should be planted? This is a matter I have been mulling over for the past three or four decades, and I have come to the conclusion that roughly half of the revegetation should consist of native (preferably indigenous) tree and shrub cover and the other half of trees grown for timber. The latter should include both native and exotic trees.
In 1999 Dr Sandra Walpole, an agricultural scientist, did a study in the Gunnedah area of northern New South Wales which examined how the productivity of a farm’s pastures varied according to the proportion of the farm that was under woodland vegetation—that is, covered by trees, shrubs and
Rows of pruned pines in 1996—five years after they were planted. Black wattles planted in conjunction with them are visible on the left.
My son David pruning pine trees at Lanark in 1998. Pruning is essential if trees are to become valuable as timber. Courtesy of Jim Sinatra and Phin Murphy
These pruned pines, plus the associated habitat planting of drooping she-oaks and moonahs, form the eastern boundary of a trial farming alley at Lanark.
High-pruned pines in stately rows: Ratty’s forestry block, planted in 1997. Shown here with my granddaughter Harriet in 2009.
The path in the extensive ‘old-world’ oak planting established in 1993. Oaks do well in our conditions, one reason being they put down deep tap roots.
Vasey Farm has a denser tree cover than surrounding properties—as shown by this aerial shot. Courtesy of Jim Sinatra and Phin Murphy
My son, Patrick, with a ‘fallen giant’—a huge red gum blown down in a storm at Vasey Farm. Courtesy of Jim Sinatra and Phin Murphy
Shorn sheep at Vasey Farm seek out shelter provided by the remnant red gums, fallen logs and natural regeneration. Courtesy of Jim Sinatra and Phin Murphy
Sheep graze in the Brolga Paddock. Whichever direction you look today, trees line the horizon at Lanark. Fifty years ago horizons were scarcely broken by a single tree.
The Other Side Reserve—a 65-acre area which we fenced off and planted with indigenous trees and shrubs to create a wildlife habitat.
The swimming hole that I dug for our children in the Other Side Reserve.
Our oldest grandchildren, Clive and Anna Fairbairn-Calvert (under Granny’s instruction), watching a long-necked tortoise laying eggs near the Other Side in 1997.
Magpie geese at the Other Side Swamp. These birds are abundant in northern Australia’s wetlands. They were once widespread in southeastern Australia. Limited reintroduction has been carried out, with some success.
The view from the front garden of Lanark’s homestead. The trees visible on the far side of the lake are manna gums planted at Graeme’s suggestion and, accordingly, are named the Graeme Gunn Plantation. Graeme said the trees would create an optical effect, making the lake look closer to the house, and this proved to be true.
An ‘alley’ between two long rows of trees.
She-oaks in the wildlife dam in the front paddock.
A view across Lake Cicely.
In my regalia after receiving an honorary doctorate in landscape architecture at RMIT University in 1997. The others in the picture are, from left: Robin Peddie (my sister), Patrick Fenton, Amanda Fairbairn-Calvert, David Fenton, Cath Fenton, Johnnie Fenton, Cicely Fenton and Charles Fairbairn-Calvert. Absent: Bronnie Fenton.
Life after Lanark: Cicely and I at about the time we left the property and moved to Hamilton.
associated ground flora, such as native grasses and herbs. In short, she set out to discover if trees made a farm more productive. In my opinion, every farmer in Australia should become acquainted with the results of Dr Walpole’s research. She found that a farm’s pastures reached a peak output when the proportion of the farm covered by trees and under-storey rose to 34 per cent. Any increase in tree and under-storey cover above 34 per cent produced no further increase in output.
This is how Dr Walpole summarised her findings:
The results indicate that the value of pasture output per farm may be increased by having a certain proportion of pasture area under dry sclerophyll or woodland vegetation. Gross value of pasture output was at its highest level when the proportion of tree area across the farm was at thirty-four per cent with no further increases in output being achieved beyond this point. These results suggest that the competitive influences of trees present in the pasture system may begin to outweigh the beneficial effects when this proportion of tree area is exceeded. It is encouraging to observe that the thirty-four per cent value estimated in this study is within the range of values quoted in previous studies.
In other words, the optimum tree and under-storey cover on a farm should be about one third of the farm’s acreage. Significantly, as she herself notes, other scientists have arrived at much the same conclusion. I know of four other papers based on research in the higher rainfall areas of southeastern Australia which conclude that the optimum tree and under-storey cover is in the 30 to 35 per cent range. If Dr Walpole and the other scientists are correct, all farmers should aim to have around a third of their land covered by trees and associated habitat. On ordinary family farms, though, achieving a tree cover of that dimension is a lot easier said than done, especially if the property is virtually devoid of remnant tree cover. This puts farmers at an enormous disadvantage—as I know from my own experience. If a farmer has remnant tree cover, he can simply fence off an area surrounding it and count on the existing trees to self-seed and revegetate the area naturally. If need be, the farmer can use herbicides judiciously to control competing grass. Without a remnant tree cover, farmers have to plant all the trees themselves.
This is what Cicely and I had to do at Lanark. And this is why, after 50 years of fairly intensive planting, I have still not got Lanark’s tree and shrub cover up to 35 per cent. The cover is now approaching 20 per cent.
If farmers are hesitating about ‘sacrificing’ good grazing land for planting trees and scrub, the key thing to recognise is that, provided the right trees are planted in the right configuration, their farm’s productive capacity will not suffer. Setting aside, say, 10 per cent of your grazing land for trees and scrub certainly does not mean you will lose 10 per cent of your farm’s income. The trees and scrub you plant should allow you at least to maintain the same income by increasing the productivity of the remaining 90 per cent of your land in the manner I have previously described.
An important flow-on benefit is to make the farmer less reliant on artificial fertilizers like superphosphate, which represents a big financial saving. The farmer is also less likely to be reliant on herbicides, as has certainly been the case at Lanark.
Dr Rod Bird had a few interesting things to say about the pros and cons of planting trees on farms when interviewed by Warren Shaw, a landscape architecture student at RMIT. The interview was part of a research project centred on Vasey Farm, which then, as now, was run by my son Patrick. The interview took place 20 years ago, but Bird’s views on whether farmers are better or worse off by planting trees are at least as relevant today as then. In his research report Shaw quoted Bird as saying:
The farmer would put in, say, one or two kilometres of shelter belts per year. Then, depending on the total—say, if he had a 400-hectare property—he would end up with five to ten per cent of land completely fenced out to stock. Now, obviously if you are doing an economic analysis you’ve got costs and you’ve got benefits. An obvious cost is you’re losing production from that area of land. The benefits are the direct effects of shelter on livestock.
Among those benefits, Dr Bird said, was a 5 per cent increase in the number of lambs weaned and a 10 per cent improvement in plant growth. For farmers, improvements like these can make the difference between a good and a bad year.
Only recently I saw one semi-government rural authority advising farmers to aim for a 5 per cent tree and shrub cover. Five per cent! To me, that seems a mere spit in the ocean. Having examined just about everything on the subject I have been able to lay my hands on, including Dr Walpole’s research, and in the light of my own experience at Lanark, I am personally convinced that a tree and shrub cover of about 35 per cent, as a proportion of a farm’s area, is the ideal. A farm that expands its tree and shrub cover to that figure will, on the one hand, have maximised its long-term sustainability and, on the other, gone a long way towards ensuring the health of the farm’s environment. However, there is often a big difference between the ideal and the achievable.
Dr Bird argues that a tree and shrub cover of around 10 per cent is as much as any farmer can aim for in his or her lifetime, unless he or she is fortunate enough to have a lot of off-farm income or unless the Australian Government decides one day to help farmers meet the cost. In my view, though, we need to lift our sights environmentally: 35 per cent should remain our ultimate goal. Clearly, the damage done to the Australian landscape by land clearing over the past 200 years cannot be fixed quickly.
At Lanark, we are working to a 100-year plan that we adopted 35 years ago. If the property were to remain in the family, the plan would probably be seen to completion by my great-grandchildren. That may seem too far in the future to worry about, yet I believe strongly that all Australians, not only farmers, need to think in time frames of this magnitude if we are to achieve equilibrium in our fragile environment. This does not mean that subsequent owners would have to stick hard and fast to the plan. But if the plan is prepared with expertise (as Lanark’s was by Rochelle Ruddock), its mapping and other documentation will remain an invaluable reference to the state of the farm at the time the plan was prepared.
The same applies to farm forestry—that is, planting trees that can eventually be harvested for timber as part of the overall farming operation. Farmers know that any timber trees they plant today will not be harvested until the 2030s or, depending on the type of tree, perhaps some years after that. Why lock up good farming land that you can use productively today in the expectation of cashing in when the trees are harvested at some far-distant date in the future?
It is a good question, for which there is an equally good answer. The point is that farm forestry does not require a farmer to plant out whole paddocks with trees. The trees a farmer grows for timber are best planted in strategically positioned blocks ranging in area from a half-acre to two acres (0.2 to 0.8 hectares). These blocks should be inter-connected with shelter belts, windbreaks, wildlife reserves and wetlands. If planted correctly, the trees will improve the farm’s production while they are growing to maturity and, once mature, will provide an ongoing source of extra income. In short, a farmer who takes on farm forestry has nothing to lose in the short term (except the time and money it takes to plant and fence off the trees) and much to gain in the medium and long term.
I strongly believe that farm forestry should not be separated from the rest of the farm. Rather, it should be part of an integrated program of tree and shrub planting on the farm. The key word here is ‘integrated’. Farm forestry trees should be only a component of a farm’s tree and shrub cover. They should certainly not be grown as monoculture plantations—that is, in areas reserved solely for, say, radiata pines or blue gums. Any farmer who intends combining habitat with a timber plantation in this way would be wise to allow the species of timber trees to determine the location of the plantation. For instance, if your choice of timber tree was river she-oak, you would look for an area with deep and rather damp soil, which river she-oaks like. Having identified such a site and planted the river she-oaks there, you would then add various habitat trees and shrubs that suited the same conditions. It goes without saying that the habitat plants should preferably be local—that is, indigenous—species. In my experience, most districts in Australia have at least one nursery that grows plants from local seed, and with luck you ought to be able to obtain your habitat plants there. In some parts of Australia—and certainly in Victoria—the local Field Naturalists Club (FNC) would probably be able to put you in touch with such a nursery if you cannot find one yourself. You can also draw on FNC members’ knowledge of local flora and fauna.
The plant you need most when you set out to revegetate a degraded area is the local pioneer wattle—that is, the most aggressive of the area’s indigenous wattles. In my own district, this is the black wattle. After a bushfire here, black wattles will be the first plants to come up. Or if you were to lock your stock out of a paddock for any length of time, you would find black wattles springing up—assuming there were black wattles growing somewhere nearby. If I wanted to establish a habitat at Lanark and there were no black wattles growing nearby, I would buy them from a local nursery and plant them. Better still, I would collect the seed and sow it directly. The advantage of wattles is that they grow rapidly and so provide shelter for slower-growing but longer-living species; they charge the soil with nitrogen; and, being relatively short-lived, they break down and hasten the development of a balanced environment.
Now, I know some farmers do not like planting black wattles because they have a relatively short life span. (It is not as short as you might think, however: at Lanark we have known black wattles to live for up to 30 years.) Still, there is no better plant for kick-starting the process of habitat reconstruction. The fact that they are not long-lived is actually a plus. It means you will soon have a supply of dead and rotting wattles—and dead and rotting trees are a vital component of any bushland reserve. Remember that when you set out to create a wildlife habitat you are not doing it only for birds and mammals. You are doing it for all native life; bugs, grubs and fungi included.
Remember, the area you fence off as a reserve should not be too small. I regard a half-acre as the minimum: an acre or more is preferable. Ideally, any area a farmer fences off for habitat should not have a gate. Why? Because if there is a gate, the farmer might not be able to resist the temptation to let stock in to graze whenever feed is scarce.