Strange generation bug

Since the most recent beta came out of been experiencing this strange generation glitch where halves of trees and water in lava source blocks randomly generate seemingly out of nowhere I'm not sure if there is something causing it I suppose that would be for you guys to determine I'll include photos to show more vividly what I'm trying to describe it's a bit of a frustrating bug to clean up after hopefully my report can help you guys fix it p.s.