Noticible missing/delayed buds in forsythia hedge row. Any ideas why?

[meichthys]

Why the strip down the center of the hedgerow?

Our top theory is that heavy snow during winter bent the bottom branches downward leaving the gap. This however doesn’t seem to explain it completely since upon closer investigation, the branches in the gap actually do have buds that just haven’t bloomed yet. Could someone provide alternative reasons why this might happen?

[astra_the_dragon]

Welcome to the forum.
It would help if you could provide a closeup as well as more information about the environment. Is a machine used to mow the lawn? What chamicals are used and how? Does it do this every year?

[meichthys]

@astra_the_dragon Thanks for the welcome!

• We are in zone 6
• Mower: We use a regular riding mower
• No chemicals are used
• The hedge has not been trimmed since they forsythia bushes were planted.
• This is the first year that it has happened

A few more photos:

[pisum]

i’m just guessing here, but typically you want to trim your hedges so that they are slightly wider at the bottom than at the top (so that the top doesn’t shade out the bottom). maybe the top is leafing out first because it just got more sun, and then the very bottom is leafing out because it’s new growth? (the middle is neither new growth nor happy without sun. so the buds have yet to break.)

[meichthys]

Interesting theory. Thanks for the input!

[trickman]

Could it be related to snowpack? If the winter snowpack was at about that height, could there have been a rain on snow event, then a hard freeze, so that the strip was within a very icy layer within the snow that froze back the buds?

[beccn]

^ I think snowpack insulation, ice and freezing buds is the most likely reason for the stripe.

What a cool phenomenon!

[meichthys]

This sounds quite plausible! Very interesting indeed.
The snow pack was about that height after a large snowfall event.