We used to do a lot of slit seeding. Two probs >> 1) uneven ground, 2) compacted soil.
In loose loam soil, I prefer to spread the seed, then power rake twice (2nd time at a 45 degree angle)
Dry or compacted or clay soils = I prefer to spread the seed first. Then core aerate multiple times. Then drag the area. This method not only seeds the areas, but it also "prepares the soil" as it relives soil compaction and creates a halfway decent seed bed.
Placing grass seed in hard/clay soils seldom works as most folks never water twice per day like they say they do.
A nice thing about our XT5 hydro aerators = you can aerate back & forth to work in the seed. Most of seeding involves seeding just the bad areas rather than entire lawns >>> usually bluegrass that died from lack of water/heat/sun/drought. But sometimes areas that are too shady (like me, lol)
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