Too much yellow rattle?

[jackieandrade]

I know people usually post about trying to encourage yellow rattle but i have so many seedlings in dense mats that they threaten to overwhelm betony and other plants in our meadow and lawn. Can you have too much of a good thing?

[Donna Cox]

Hi Jackie, I've had areas that look like that and have thought the same. I don't know if Yellow Rattle parasitizes betony as well as grasses; it also feeds off legumes like the trefoils. If you're concerned about it, just stop it from setting seed by cutting it. Very grassy sites are undoubtedly made more species-rich by the introduction of YR, my orchard meadow being one. However, if a site already has a relatively good mix of wildflowers I'd be cautious about adding it. The ecologist Jerry Tallowin said Yellow Rattle's presence in grassland may well assist the establishment of more common plant species such as Ribwort Plantain, Catsear, Black Knapweed, Crested-dogs Tail and Sweet Vernal Grass.

[Steve Pollard]

Jackie - that betony currently looks like a prize specimen! As an experiment, if you have another nearby plant, you could always control the rattle around one of them to see if it has any effect. The rattle may just be suppressing the grass around the betony, meaning that the betony actually has less competition and does better! Rattle also dies in mid summer, whereas Betony is flowers in late summer, at least in my meadows. Donna, to add to that list - orchids also do very well in meadows that have abundant rattle.

[Alice]

This is very interesting. We had a lovely meadow in our front garden, including buttercup and moon daisy, and then introduced yellow rattle in some other areas where the grass was still long. It didn't really like those long grass areas and instead moved into the meadow and moved across it gradually (the front line moving a few feet a year) wiping out all but Ribwort Plantain, Catsear, Black Knapweed and self heal. I was sorry to see the diversity reduce. However, since then a few common orchids have appeared, so it seems they are not a target. I do like what we have now, but it's certainly different, and feels less diverse.

[GorenFarmSeeds]

Hi Jackie. We roll some of our meadows in late april/may to reduce yellow rattle. This won't affect the betony. Grazing and trampling will also have the same effect. Cutting high and removing the cuttings in early June will also promote betony and devisbit Scabious and again reduce the yellow rattle the next year. Finally leaving the sward long overwinter or not cutting for one year will also reduce yellow rattle the next year. Food for thought.. you can't buy yellow rattle in Switzerland and is treated as an unwanted weed in meadows as it was here when we used meadows as a source of feed for animals. This is where the summers are hot and dry and grasses struggle anyway.

[NigelPemberton]

Hi Jackie. Yellow Rattle will parasitize other plants if there is no grass nearby and most meadow plants will grow weaker with Yellow Rattle than without. Betony plants in a garden border for example will usually be larger specimens with more flower stems than ones in a meadow. However I think the best thing you can do is simply to allow nature to take its course and over time a natural balance will emerge. After all it takes 15-20 years for a new meadow to mature.

[Donna Cox]

An interesting article on the impacts of parasitic plants on natural communities:
https://nph.onlinelibrary.wiley.com/doi ... 05.01358.x

And this article just on Yellow Rattle (Rhinanthus minor) suggests it has a wide host range:
https://nph.onlinelibrary.wiley.com/doi ... 07.02013.x

[Hayden]

It was my delight to live for many years alongside a decades old wildflower meadow on Dartmoor, fabulously diverse until one year yellow rattle was introduced inadvertently by a contractor coming to make small bale hay. The first bales out from the previous baling location contained yellow rattle which seeded and took hold in a clearly de-marked area where the bales had landed. The results within a few years were horrible to witness - complete yellow rattle takeover. Cutting certainly knocked it back, but several years later, the meadow has never fully recovered.
I'm so pleased to see some balance to the debate appearing in this forum as yellow rattle is so often portrayed as the go-to, must-have meadow-making plant. Needless to say, I don't want to see yellow rattle anywhere near my little meadow-in-the-making.