Brief Description: 
When placing a lightning rod whilst looking at the edge of a grass hit box, it will place horizontally.

Steps to Reproduce:
1. Place a piece of grass down.
2. Place a lightning rod on the edge of the hit box.
3. You will notice that it places horizontally.

Observed Results:
The Lightning Rod places horizontally.

Expected Results:
The Lightning Rod should place vertically.

Screenshots/Videos:

I've attached two images which show that if you place the lightning rod of the edge of the hit box, it will place horizontally.

Notes:

This also works with dead bushes, crimson roots and warped roots.