Fen Peas

This is an odd one! Drilled on the same day, into very good moisture, it had rained the day before, and 15% or thereabouts, have emerged at a later date. The picture suggests that the plant on the right has had to grow around some obstacles. However the seedbeed can be described as fine and drilling conditions superb. Any ideas? Answers on a postcard, or e-mail please!