As verbs the difference between overseen and overseed
is that overseen is past participle of lang=en while overseed is to replenish (a lawn, etc.) by adding more seeds.
overseed
English
Verb
(
en verb)
To replenish (a lawn, etc.) by adding more seeds.
*{{quote-news, year=2007, date=April 12, author=, title=Another Path to Splendor in the Grass, work=New York Times citation
, passage=Plant or
overseed with the right grass for the spot. }}