I wouldn't go for necessarily the cheapest option, a good reseed will last years and pay you back the cost, a bad one will cost you more as you'll be redoing it after a few years.
I think like a lot of things in farming no 1 method is the answer to every problem, it all depends on the ground your on, the weather for the year up to/ around reseeding and what the field is like to begin with.
If you need to reseed due to compaction a direct drill system is pointless as your not addressing the issue, on the other hand if your on Stoney ground you may have no option, also you could mole plough ahead of direct drill if it suited,
Mole plough is or the likes is why i say about weather, if ground is soaked it will just smear through the ground and not do much, but if its dry it will open up great drainage,
Another factor is how you can prepare the field, we mowed a field then disced it with heavy duty disc and did a great job, said great well use that from now on, ended up ploughing next time as we couldn't mow it and disc wouldn't work.
So basically i wouldn't say one method will always suit you have to be flexible and pick and choose according to the conditions infront of you in the particular field at the particular time!
(Oh n sorry for the essay!!
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