Pigs Vs couch/ quack grass who will win?

I have about an acre of couch grass: http://en.wikipedia.org/wiki/Elymus_repens that ultimately I would like to use 1/3 forest garden, 1/3 tree nursery, 1/6 perennial food crops. 1/6 Annual crops.

I'd obviously like to eradicate the couch/quack grass as much as possible before planting perennials. As it is a shallow soil I'd also like to build soil volume as much as possible too.

I'm leaning towards using pigs intensively for a few months to eat the Rhizomes, based on this article: http://www.organicgrowersalliance.co.uk/sites/default/files/OG20%20Using%20Pigs%20to%20combat%20Couch%20Dibben.pdf

I'm thinking of rotating the pigs around the field using electric fencing, as soon as they leave a patch planting a quick growing cover crop of Mustard (Sinapis alba); (sow in March to September). to compete with the couch & stop nutrients being washed from bare soil, then after about a month or so rotating the pigs back through the same ground to get the rhizomes as they are re-sprouting.

After the second pass i'd plant a longer term cover crop. For this I'm thinking of planting a slightly adapted Landsberger mix http://www.seedaholic.com/green-manure-landsberger-mix.html#Edibles

So in September sow:

Italian Rye (Lolium multiflorum) (annual)
Rye is one of the best manures for winter use, as it gives good crop cover to help prevent nutrient leaching. It is a hardy annual and an excellent nitrogen lifter and it can lift and release up to 90% of nitrate to the next crop. Rye has deep penetrative roots that help to break up heavy soils and so improve soil structure.

English Early Common Vetch (Vicia sativa) (annual)
Also known as ‘Tare’ or simply ‘the vetch’ it produces a lot of bulky foliage that improves the soils fertility as it fixes nitrogen and helps add organic matter, improving the texture of the soil and suppressing weeds. Useful for heavy soil. : This annual legume is hardy and overwinters well, even in heavy soils

Essex red clover (Trifolium pratense) (perennial): This hardy perennial legume overwinters well and can be left in for two or three months or for one or two years after sowing; good for loamy soils; sow March to August.

Hopefully I will then have a permanent cover of red clover to dig in as I get around to doing bits.

Any thoughts/ Comments? Should I just reach for the Roundup?!

Thanks

Sam



Some info about the site:

Zone 9
Mean annual temperature 10.2c -12c
Nitrogen 0.24
PH 7
Olsen-Phosphorus (mg/kg) 2007: 47.32
Soil Depth: SHALLOW
C:N ratio 2007: 11.23
Soil Group: LIGHT(SILTY) TO MEDIUM(SILTY) TO HEAVY
Soil Texture: LOAM TO SANDY LOAM
Grain Size: ARENACEOUS
ESB Description: SANDSTONE
Dominant broad habitat: Arable and Horticulture
Bulk Density (g cm-3) 2007: 1.16

Annual ryegrass can become an invasive weed. The folks at the talk about cover crops at the Small Farm Trade show last year pretty much said DO NOT PLANT it if you were going to plant crops after it.