Here is a neat trick for Kikuyu control - discovered by accident. Spoiled haylage kills kikuyu!
First, mow the kikuyu , then spread spoiled haylage* over the Kikuyu, about 150-200mm thick, covering all - no need to trample it down, just make sure kikuyu is covered.
When we moved to Kaukapakapa we had too much grass and not enough animals the first spring, and so we got a contractor in to make haylage. We managed to get 12 bales off 2.5 acres, and at around 500kg each they are impossible to move without major capital equipment. The problem with the monster bales on small holdings with few cattle is that it is virtually impossible to get the beasts to eat a whole bale. They give it a good go, but there is generally around 25-30% wastage.
The big guys feed out by rolling the bales with specialized feedout trailers. But the little guys open the bales and let the cattle eat from the bale.
So the maths works out - 25-30% of 500kg multiplied by 12 equals (125-150) times 12 is 1.5-1.8 tonnes of smelly rotting grass - what to do with it was the question, so I decided to spread it out on kikuyu that was surrounding the spot where I had decided to grow veges for the family.
When I moved it to the vege garden I found that where it had lain there was nothing but bare earth and lots of worms.
Basically, the procedure is to mow the Kikiuyu short, then spread a layer of spoilt haylage to about 150mm deep over the ground. (You can tell when it has spoiled, once it gets air into it, the haylage develops an ammonia like smell, and the cattle will not touch it. They eat all around the spoiled are but donít touch the bad stuff.)
Simply open up a small hole in the spread haylage, drop in a seed potato, and cover, either with soil or more haylage - a small amount of soil gives a better result.as the unrotted haylage can cause the seed spud to rot. This also works with kumara shoots, and makes kumara harvesting much easier. Take care not to make the hole too wide or the kikuyu will grow back up through the soil.
The other thing about the haylage is that the process of making it seems to slow down the rotting process, so the problems of growing potatoes and kumara in green rotting grass donít exist. In fact it can take nearly 12 months for the full breakdown to occur. The potatoes sprout and grow up through the soil, spreading the tubers under the haylage, so when it comes to harvesting, it is simply a matter of lifting the foliage and the whole plant comes away in your hand, with the potatoes still attached. They donít bother growing down into the soil below the haylage (as long as the layer is deep enough). The potato crop is probably only about 80% of what it could be, but hey, no digging, no chemicals, no more kikuyu,
The real magic appears when the harvest is done. You can scrape away the remaining haylage which has a tendency to dry out on top and just looks like dead grass, and all the kikuyu is dead. Even the below ground roots have died and rotted, the worm population is phenomenal, and you can now dig the resulting garden bed with a spade or fork easily.
Given that the kikuyu is gone, the only thing to make sure of is that any runners from the outside edges are not allowed to grow back into the beds.
And thatís it. Simple but effective, and not a chemical in sight. I have done it on two areas of heavy infestation, over two years. There are obviously some naturally occurring compounds produced by the fermentation processes involved in the making of haylage, and further compounds produced during the spoiling process once the air gets at the haylage. Maybe a research institute would like to work out what the chemicals are, but this is a bit like the old farming techniques at present. We donít necessarily understand the science but the results prove themselves.
The other more laborious method is to take the top spadeful, including all the kikuyu roots and dump it in the chookrun. This involves double handling because you have to take the soil from the chook run and replace what you have dug out but six weeks later there is no more kikuyu. Putting the chooks on the kikuyu covered ground doesnít work as well, because they canít get down into the root zone.
(*Haylage is baled silage - the big green round bales you see dotted around the dairy and beef farms across the country)
Mike and Sue McKeown are townies who have long held a dream to move to the country which they realised on purchasing five acres at Kaukapakapa North West of Auckland. When Mike supplied this article, they had 40 fruit trees in their orchard and only needed to buy bananas and a few exotics. The summer garden took care of all the salads, and the spuds, kumara, pumpkins, watermelons, sweet corn and beans were plentiful. The economics of sheep, beef, pigs and poultry were "somewhat questionable", but the meat and eggs tasted like nothing that ever came from a shop. That plus the exercise - and the joy of having kids who visit being absolutely astonished that things grow in gardens and on farms and donít just come from supermarkets and McDonalds - "makes it special".