I think I remember an article in SF a few years ago comparing the planting speeds of different metering systems.

This is not a blue vs green or red thing but the physics of a finger pickup vs a vacuum or pressure metering system.

Francis Childs was know to really push slow planting speeds as one of the keys to his yields.

I think a finger pickup in good condition should be able to plant with good stands at 4.5 mph.

Going faster the stand deteriorates as the dynmics go up exponentially with speed, not linearly.

A vacuum meter does not have the same mechanical physics limitations but there are others.

Anyone planting over 6 mph is losing something. Conditions such as terrain, seed size and shape, row cleaner performance/meter bounce etc all interact to affect speed/stand relationship.

I would certainly not criticize anyone for planting at 4.5 mph in any color planter!

This is one of the reasons why folks are going to wider planters - to be able to keep acres per hour up without increasing forward speed beyond the ideal for their conditions and reducing the quality of the stand.

jmho.

Jim at Dawn