The term "bulrush" actually refers to any of the annual or perennial grasslike plants constituting the genus Scirpus, especially S. lacustris, in the sedge family, that bear solitary or much-clustered spikelets. Bulrushes grow in wet locations, including ponds, marshes, and lakes. Their stems are often used to weave strong mats, baskets, and chair seats. Bulrushes may act as a filter, absorbing poisonous metals and toxic microorganisms, thus helping to reduce water pollution. In Britain, the term bulrush refers to either of two cattails (Typha latifolia and T. angustifolia). [Britannica].
Locally we find the most common one is the Great Reedmace which most of know simply as bulrushes.
BULRUSHES or GREAT REEDMACE : Typha latifoli
Many of us will recognise the bulrush from story books such as that about Moses who was found as an infant amongst them. If little else it conjures up an iconic image of the flower heads and also indicates how widespread such plants are.
The flowerheads are like sausages stuck on sticks ready to barbeque. Attractive in an abstract geometric sort of way. The spire or spike out of the top has the smaller male flowers.
It is found along many of our local waterways and wetlands with the flower heads most noticeable in June through to August.
Bulrushes in the wetlands of the RSPB Loch Lomond reserve in June. Some are already loosing their fluffy seedheads which will be diseminated in the wind to aid pollination.
BRITANNICA : https://www.britannica.com/plant/bulrush
WIKIPEDIA : https://en.wikipedia.org/wiki/Bulrush