Inoculating seed adds effective bacteria to the seed before planting, making sure there is enough of the correct type of bacteria present in the soil.
A massive biomass producer and will provide many kilos of above ground vegetation that will reduce to a wonderful much once the root system has been cut.
Ensure that you cut the root system once the first flowers appear as you do not want it to re-seed in place.
Note that the seed pods are toxic to humans, but they can make a great fodder for cattle and sheep.