A paper I read recently, on Scots-Irish Music, maintained that - "In the twentieth century, the fife and drum tradition faded in all but a few heartland areas, and the Bb flute bands came to dominate the parading scene. Eclectic in their tastes, they adopted military marches and music-hall tunes as well as tunes from the fifing tradition, often transformed from the swinging hornpipe time which suited the slow progress of the Lambeg drum, to a more conventional quick-march time. In more recent times, film scores and pop tunes have been adopted with equal aplomb.
The appearance of the ‘part-music flute band’, again towards the end of the 19th century, came to form a bridge between the local folk traditions and those of European art music, as they developed from playing folk tunes with simple harmonies, to becoming virtual ‘flute orchestras’, encompassing music by composers as diverse as Sousa and Verdi, and adaptations of music from more far-flung traditions such as samba and tango."
Read the whole paper, by ‘Queens University's – School of Anthropological Studies’ at: 
For an excellent history on the Bb instrument check out the 'Miller Wicks' site at: 
At the moment there are 26 flute bands registered with the
'Northern Ireland Band Association': 
The association started way back in 1907 with only 13 bands.
Each year, during February, they hold the annual
'Flute Band League Own Choice Contest'
From a browse through their websites it would appear that most are heavily involved in competitions & one bands records I looked at for last year showed that they had entered no fewer than 34 competitions, which, when you consider the amount of rehearsals that would also mean, would probably leave the musicians little or no time for any sociable playing, the sort that folk musicians tend to thrive on & live for.
Wooden, Concert or D Flute
The larger simple system wooden, or concert, Flute hasn't really been a part of Scots-Irish folk traditions, mainly perhaps because it is a softer sounding instrument & not suited for use with marching bands. However the Irish Music tradition make full use of this instrument's potential in informal settings, where you see it played in every Pub Session in Ulster.