There's an excellent article in the 15 June 2018 edition of the Times Literary Supplement
by Jem Poster that examines Jefferies' influence on Edward Thomas'. Here's the beginning:
Excavating
the future
Richard Jefferies and Edward Thomas: a spiritual
affinity in poetry and prose
When Edward Thomas wrote his biography of Richard Jefferies (published
in 1909) he was paying homage to a writer who had influenced him, at the
deepest level, from childhood onwards. We should beware of over-simplifying the
complexities of literary influence – shared concerns do not necessarily imply
the direct passage of ideas from an older to a younger writer. But it’s clear
that Jefferies’s works played a crucial role in Thomas’s intellectual and
imaginative development, and that Thomas’s admiration for his predecessor
constituted a form of filial devotion. When he discussed his early reading in
the memoir posthumously published as The
Childhood of Edward Thomas, he accorded Jefferies an importance allowed to
no other writer mentioned in that context.