Pods from the tagasaste (Chamaecytisus palmensis) on the swale. A new prostrate cultivar has been developed for grazing which eliminates the need for bi-annual cutting.
Muck and mystery is the description that a scientist colleague of mine gave to permaculture when I told him I was interested in it. Muck is certainly right - I have come to love mucking around with muck in its many soil-improving forms: manure, compost, mulch, worm castings, and so on.
As the for the mysteries, well they are slowly revealing themselves as hard-won knowledge. And lately I've been to some great workshops and field days that have thrown even more light on the ways in which we may be able to design farming systems that provide ecosystem services.
Pasture cropping field day with Col Seis
In October, I attended a pasture cropping field day outside the pretty Victorian town of Avenel, 114 km north of Melbourne in the Goulburn River Valley. NSW farmer Col Seis, from Goolma in central west NSW, gave a workshop on pasture cropping, hosted by the Broken Catchment Landcare Network, an umbrella network of 23 landcare groups operating in the Broken and Goulburn Catchments.
This workshop was a great way to round off the academic part of my year - in second semester I did the subject 'pastures and rangelands'. While native grasses for grazing was on the course material, pasture cropping was not.
Pasture cropping refers to the practice of no-till sowing annual crops directly into living perennial pastures. In Australia, pasture cropping tends to refer to winter cereal crops sown into summer-growing native perennial pastures. The pasture can
be grazed right up to time of sowing and the stock is put back on the pasture after harvest to graze stubble and green perennial grasses.
In Col's case, on his property Winona, this means direct drilling winter cereals (oats, wheat) into native grass pastures made up predominantly of summer-active native grasses such as Kangaroo grass (Themedia triandra) but also some winter-actives such as Wallaby grass (Austrodanthonia).
Conventional broad-acre cereal cropping in south eastern Australia has tended to involve either fallow periods where the paddocks are sprayed out with herbicide to prevent annual weeds prior to the next sowing or 'ley farming' in the drier inland parts of SE Australia. Ley farming involves a pasture phase of 1-5 years duration (pastures tend to be annual-legume dominated - clovers, medics) followed by a cropping phase. As with the higher rainfall areas, the paddocks are sprayed out for annual weeds prior to cropping.
In contrast, pasture cropping maintains perennial ground cover on the paddocks at all times, and with vegetation (native perennial grasses) that is well adapted to the soil. The potential advantages are an increase in soil structural stability, and hence water retention, decreased soil erosion, decreased inputs (including decrease in herbicide use), and more efficient use of rainfall which has the potential to reduce salinity.
Col's presentatation was both down to earth and inspiring. He comes from a pioneering farming family and has the experience, knowledge and results that make farmers and scientists alike sit up and listen. He talked specifics about grazing management strategies, advising heavy stocking (also called 'mob stocking') of no more than ten days duration, followed by 30-100 days of recovery depending on stage of growth of the native grasses, and growing conditions. It was interesting to hear the extent to which the recovery period is based on close observation of pasture growth.
The heavy stocking rate is designed to:
• reduce the bulk of the grass
• manage weeds
• produce litter
• prune perennial grass roots to conserve water
• transfer nutrients to paddock
While annual grasses and legumes don’t like growing through litter, perennials do.
The grass litter and trash generates mulch that works to limit the weeds and is also trampled in by stock, contributing to soil organic matter.
For more information on pasture cropping, including some scientific research that's been conducted on Col's property, see:
- Description of pasture cropping from Landcare: www.watershedlandcare.com.au/pasture-cropping-at-winona-stud.html
- CSIRO field experiment on Col's property measuring biomass, total cover, soil water and nitrogen: www.pasturecropping.com/index.php?option=com_content&view=article&id=50:pasture-cropping-effect-on-biomass-total-cover-soil-water-a-nitrogen&catid=40:research-findings&Itemid=63
- The Birchip Cropping Group's pasture cropping trial: http://www.bcg.org.au/news.php?category_id=181
Agrowplough, which was demonstrated. Agrowploughs are Australian designed and built, and have been designed specifically for zero-till cropping and pasture systems.
Agrowplough coulters and tines mounted on a display unit. The shape of the tine is designed to avoid soil inversion (the dragging up of deeper, less fertile soil up to the surface where it is mixed by the action of the plough), shear and compaction.
All grassed up
Then, in November, I spent a weekend peering closely at native and introduced grasses on the southern Mornington Peninsula. Dr Graeme Lorimer of Biosphere Environmental Consulting ran this workshop, which was organised by a group called SPIFFA (Southern Peninsula Indigenous Flora and Fauna Association).
We learnt about grass morphology and how to use this to identify grasses using different sorts of keys. And we looked at grasses down a microscope and saw the amazing action of grass awns that spiral and bend in response to moisture levels.
Rain-fed garden madness
Growing in the patch now: garlic, potatoes, tomatoes, rhubarb, sweet corn, and jerusalem artichokes. Groundcover of various clovers and woolly vetch, for weed control and nitrogen fixation, are cut back in the growing season to allow sun to reach edible seedlings. Borders include comfrey (flowering now), canna lillies, wormwood and nastursium.
In the patches, keeping check on rampant growth brought on by the rain and humidity has been a big job.
Herb patch, Peninsula, the curry plant (Helichrysum angustifolium) is the light-couloured shrub towards the back of the patch.
In the peninsula herb garden, I've planted a curry plant (Helichrysum angustifolium) which is doing well. The horseradish is also kicking along and I should be able to harvest it and maybe even divide it soon.
The garlic is ready to harvest so I've started digging it up and hanging the bulbs to dry on the line, after which I'll plait them and hang them up in the shade between the tanks. Should be enough there to last us at least 6 months.
In the inner-city patch, yarrow seems to like its sunny spot beside the pergola. Chervil sown in October responded to the heat and is now paying its way in fish dishes, along with the French tarragon.
In the bathtub I've put a couple of pots of water chestnuts - the soil in the pots is held down with stones. The bathtub is aerated (for mozzie control) with a small solar-powered bubbler.
Loquat and nastursiums in blue pot, inner-city patch. Marjoram and rosemary to the left; bay tree to the right. Bottlebrush behind.
Seedlings of cucumber, eggplant, zucchini and tomatoes are doing well and the beans have already reached the netting of the domes. The grapes on our pergola have finally taken off, as have the two (male and femaile) kiwi fruit plants - we are well on the way to getting good shade coverage for summer.
Cucumber seedlings (mini white) ready to be planted out, inner-city patch
Came across this excellent podcast from The Guardian website on on food security and food justice. It asks whether crops and increasing corporatisation of agriculture are really the only true solutions to hunger in the world. We learn that food security is as much a political problem as an agronomic one, perhaps more so. Interviewees include Raj Patel, author of the fabulous book on food justice Stuffed and Starved; Olivier de Schutter, the UN's special rapporteur on the right to food; and Oxfam UK's head of research Duncan Green.