Yellow Rattle Springwatch 2011

Spring has finally arrived at last in our meadows with the emergence of yellow rattle seedlings.

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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 frost and snow. 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 and so are useful spring-watch indicators.

This year's yellow rattle emergence has been a little tricky to pin point. First signs of stirring seedlings were observed both in Norfolk and our farm in Bath about two weeks ago in the mild spell of mid February. The colder weather that followed however kept things in limbo. Growth has now resumed with the main emergence in this the last week of February.

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. 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 27 February 2011,
Category: News