Green wood (Oak) is much worse than seasoned Oak. You will need cover in there with small openings between the branches for small fish, You will need enough cover to equal 3/8 to 1/2 acre of the pond, depending on whether your pond is 1.5 or 2 acres. So, your journey in putting cover in the pond has just begun. Welcome to the forum!

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).