Yellow rattle spring watch 2019

Yellow rattle emergence in our Norfolk meadows began on schedule at the end of the first week of March. We had wondered whether the record winter temperatures at the end of February might bring germination forward. This does not appear to be the case in Norfolk, but on our farm near Bath germination was first seen 10 days earlier on 27th February.

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Seeds that were either sown last autumn, or shaken from hay in summer, have spent the winter lying on the wet soil surface exposed to winter weather. Rather than being an endurance test, as one might imagine, this is just the stimulus yellow rattle seeds require: 3 or 4 months of prolonged chilling release yellow rattle seeds from their enforced dormancy. In this primed condition the seeds are set to germinate at the first sign of spring.

As with bumblebee queens, frog-spawn and other indicators of spring the first appearance of yellow rattle varies from year to year: the first week of March is in our experience typical for eastern England.

This synchronised early emergence of yellow rattle is critical: the seedlings must grow quickly to grab space before the surrounding spring flush of grass closes in and denies them light.  In parts of our meadow the grass looks healthy, poised to grow away strongly as spring takes hold. If it does we will top the meadow to keep this lush grass back and help the rattle seedlings grow through.

If successful, the young plants will soon attach themselves, via their roots, to nearby grasses and other plants to extract nutrients from them. Yellow rattle will flower in early summer and complete its life cycle when its seeds ‘rattle' out to fall back to the ground in July.


Posted on 09 March 2019,
Category: News