SPRING is a wonderful time for a woodland walk, and one of the most welcome and distinctive smells and sights is the garlicky aroma and white, star-like flowers of Wild Garlic or Ramsons (Allium ursinum)(main photo).

In April the small white flowers appear, held together in a bouquet-like inflorescence, with all the short flower stalks meeting at the same point, like the spokes of an umbrella. Hence the botanical term – ‘umbel’ from the Latin for parasol or umbrella.

The flowers are pollinated by insects and ripen into seed capsules containing black seeds, which is the plant’s main form of spreading.

The story so far is one that everyone will recognise, but in recent decades there have been two non-native Alliums which have spread, almost unnoticed as they superficially look very similar. These are Few-flowered Garlic (Allium paradoxum) (photo insert – bottom left) and Three-cornered Garlic (Allium triquetrum) (photo insert – bottom right), both introduced by our horticultural and botanical ancestors.

Few-flowered Garlic originally from the Caucasus was introduced into Britain in 1823 and escaped into the wild near Edinburgh by 1863. Since when it has spread in an invasive manner south and is now frequently seen along streams and riverbanks in Wharfedale. It does what it says on the tin, and only has one or two, or sometimes no flowers, these having been replaced by bulbils. This efficient vegetative method of spread accounts for its invasive nature. Preferring wet habitats, the bulbils will break off and spread downstream.

Three-cornered Garlic, originally from south-west Europe was first cultivated in Britain in 1749 and was first established in the wild in Guernsey by 1849. Since then it has spread northwards, and now can be found throughout England, including Wharfedale. The flowers are much like a white-flowered Bluebell, with a thin green stripe on each white petal or tepal. All three Alliums have triangular stems, but this is particularly pronounced in Three-cornered Garlic with ‘wings’ at each corner.

Three-cornered Garlic has an even more ingenious method of spread – Myrmecochory – where the seeds are dispersed by ants. The seeds have a fatty appendage or elaiosome which the ants love to eat. The seeds are taken back to the nest and gorged upon, after which they are discarded outside the nest and are ready to germinate next spring. How clever is that?

All three Alliums can be used to make Garlic soup or butter, and pesto. Happy foraging, and don’t forget to have that woodland walk before the spring spectacle is over for another year.

www.wharfedale-nats.org.uk