The key to gorse’s success lies in what happens when it’s flowers fade. Now if you stand by a gorse bush on a warm June day, and listen very carefully, you may hear something surprising. As the gorse pod matures, it twists and bursts open, sending seeds flying through the air. But on the heath the seeds can dry out, so the gorse has a rather nifty way of getting them to somewhere cool and moist.
If you pick off a pod and break it into your hand, you’ll discover that the seeds themselves have, on their sides, a little blob of yellow. Now that serves a very special purpose, and I’ll show you what.
The yellow blob is a tiny store of fat, and it’s there to pay for a highly efficient courier service. It’s a delicacy for foraging ants, but they don’t get their payment until they deliver their part of the bargain. Foraging ants tend to be the geriatrics of the colony, so their old worn-out jaws can’t separate the fat from the seed, instead they carry it back to the nest. In here the younger workers can easily remove the tasty treat using their sharper jaws, so the seed is delivered to it’s destination. Ants though, are tidy, and any litter in the nest is cleared away in no time, but the seed delivery stays right where it is. The fat store was a kind of handle, so once it’s removed the ants have no way of carrying the seed away. Protected in the cool moist nest the seed germinates, and starts to grow into a brand new gorse bush, all courtesy of the local ants.