leafmine

sunday, august 25, 2024 a scan of a small, mostly intact leaf. there is a linear path through the leaf, starting narrow and getting wider as it progresses. at the end of the path, there are holes.

a scan of a small, mostly intact leaf. there is a linear path through the leaf, starting narrow and getting wider as it progresses. at the end of the path, there are holes.

this morning, ben and i took a walk through the park to look for bugs and found this perfect leafmine. some insects lay their eggs between the outer layers¹ of leaves, giving their offspring both shelter and easy access to food. after hatching, the larva eats its way through softer middle layer² of the leaf, creating a trail, or “leafmine”, behind it. this is a lovely example because it shows such a clear picture of this bug's journey. it started off tiny, its path constrained by the veins on the leaf. as it ate, the bug grew larger and the path it made for itself widened. at a certain point, it became strong enough to make turns across the veins and started taking a more winding path. at the end, the leaf was stretched thin, so the last part of the path has started to dry out and acquire holes. the bug is gone, but the leafmine remains as evidence. a vignette. a little painting on the leaf.

the epidermis. our outermost layer of skin has the same name.
the mesophyll. plant-specific; full of chloroplasts.