Dan Douthwaite top scored with 39 but Glamorgan were bowled out for 134 after winning the toss and electing to bat first against Essex at Sophia Gardens.
In reply, Essex reached 92/2 with Nick Browne 50 not out before bad light brought an early end to the day's play.
“It was a tough day with the bat. Fair play to Essex, and Snater in particular, I thought they bowled really well. That’s something we can take inspiration from moving into day two,” said Douthwaite.
“We didn’t execute properly. If you hit the right length it was a challenging wicket to play on in the morning
“It definitely wasn’t a 134 wicket and we are hurting from that. I couldn’t think it was my finest knock and I was at my free-flowing best.
“I am not going to put our performance today down to a clack of red ball preparation. We are going to have to claw that back over the next three days.”