Sam Statham Workshop Presentation
ฝัง
- เผยแพร่เมื่อ 13 ธ.ค. 2024
- Managing non-vine vegetation in and around the vineyard to deliver production benefits
Today we grow 20 hectares of grapes and make and bottle all our wine on site. We also grow and process about 10 hectares of olives, and about a hectare of figs, about 5 hectares would be replanted native trees, gardens and accessways. The different crops are in 1 to 8 hectare blocks and are quite mixed up with eachother. The native trees are planted around all the edge areas and roadways. Birdwatchers have documented well over 40 species of birds here.
The tree plantings have created resilience in the vineyard firstly through microclimate: the shelter belts create areas of wine protection and shade for the vines and you can see the benefit in the fruit when its protected from the blasting how westerly sun and wind. Our mistake was not to plant more of them, with more under-storey species, and with the strips closer together, as them especially on west facing slopes. Our shelter belts are about 250metres apart, and maybe 80 metres would have been better. One idea we are thinking about it planting olives in strips inside vineyards as shelter belts. From a business perspective, the olives and figs actually create resilience by performing well during drought, when the vines tend to struggle.
The production benefits of the other plantings would be mainly in the habitat they provide for insects and animals. For example I have noticed predation of vine moths by wasps, lacewings and spiders, as well as birds. Again there is quite a lot of edge effect and these benefits may have been greater if we had planted shelter belts closer together. Also there is definitely a lot more insect and bird diversity where there is water, and we have two old farm dams which are often full.
I must say that I am only a farmer and not a scientist and I would love it if this presentation could inspire a budding researcher to use Rosnay as a testing and research ground.
The question of biodiversity inside the vineyards is different. I am sure that mixed groundcover makes the vineyards more resilient. Our vineyards have been certified organic since we planted them in 1997 and so we certainly have a great diversity of annual introduced grasses like ryegrass and summer grass, perennial native grasses such as wallaby grass and kangaroo grass, introduced perennials such as paspalum, phalaris, couch, kikuyu and johnsons grass - these are our main weed species. There are plenty of self seeding clovers and medics, and broadleaf herbs such as wireweed, horehound, through to saffron thistle and self seeding cover crop species such as chicory.
Our view of these plants is that if they can be kept down low and not up in the vine canopy they provide a net benefit by protecting and building soil. Especially if they are annuals, as they grown and decay each year thus building topsoil, especially the taprooted plants like pattersons curse, capeweed, thistles, squareweed, dock and chicory. The perennials are harder to manage. Some of them are beneficial, like horehound, which seems to have huge fungal populations around it. This could be a good area for research.
The other, prehaps most important benefit of the groundcover plants is their use for grazing sheep. We have been grazing sheep in the vineyards for 25 years and find that its best to put large numbers on small blocks, and try to maximise the grazing season by starting right after harvest and finishing after budburst. Or even better, grow the vines on a high trellis and graze through the summer. However we have found that when you do that the sheep learn to walk on their hind legs.
In any case there is the benefit of the manure on the soil, and the rotational system leads to more plants per square meter and more domination of winter species so that you get less summer weeds.
In terms of managing the downside in order to maximise yield, is hard when you are irrigating using drip under the vine. In my experience, the weeds will adapt to whatever you do, whether its cultivation, mowing or grazing. So by putting water, and fertigation, right under the vines you will get more weeds there. But thats also the place where the weeds are the hardest to control.
We eventually decided to give up the unwinnable war and put new drip irrigation up the middle of the midrow. We are still getting the same weeds but its much easier to mow them and they still build soil without being such direct competition for the vines. Young vines might take a while to get their roots out but older vines adapt to the new watering point within a couple of seasons. Again I would invite any researchers who are interested in this to use our farm for research in this. I am interested in using things like humic acid and hydrogen to stimulate root growth as well as the role of soil fungi in moving moisture laterally through the soil.