wood shavings
杮 centers on thin fragments of wood produced by planing or carving: wood shavings.
杮 combines 木 (tree, wood) with 巿, which likely contributes the sound. The character expresses wood shavings or thin wooden fragments.
The left side is a tree 木, and the right side 巿 looks like a cloth or something spread out. Picture thin wood shavings curling off a plank like delicate cloth strips.
For ハイ, imagine a high-pitched plane shaving wood: the sound 'high' cues ハイ while the shavings fly off the 木.
chopped wood; wood chips