The field system at Kilballyowen is not marked on any Ordnance Survey historic map, and there is nothing on the surface to suggest it is there. What makes it stranger still is the shape at its centre: a distinct triangular cropmark formed where the linear features converge, sitting within a broader subrectangular area of roughly 9.4 acres. A visitor walking the slope would see only grazing land; a pilot overhead would see something quite different.

The monument came to light in 1986 during the Bruff aerial photographic survey, recorded as survey image Bruff 251 (AP 5/2053). Cropmarks of this kind appear when buried features, such as old ditches, walls, or soil disturbances, affect how the vegetation above them grows, particularly during dry summers when differential moisture retention becomes visible as variations in grass or crop colour. The Kilballyowen system sits on a gentle north-west-facing slope that was once part of the deer park associated with Kilballyowen House, located about 140 metres west of the townland boundary with Knockainy West. It does not exist in isolation: a cashel, which is a type of early medieval stone-walled enclosure, lies just 20 metres to the east, a further enclosure sits 55 metres to the north-east, an earthwork 95 metres to the south-east, and another enclosure 130 metres to the east. The density of monuments in this small area suggests long and layered use of the landscape. Subsequent aerial imagery, including Ordnance Survey orthoimages taken between 2005 and 2012, Digital Globe images from 2011 to 2013, and a Google Earth image dated 20 September 2020, have all confirmed the cropmarks remain visible.

The field system is not accessible as a formal heritage site, and because it leaves no surface trace, there is little to observe on foot. The most instructive way to examine it is through publicly available aerial and satellite imagery, where the subrectangular outline and the triangular formation at its centre are clearly legible. Those with an interest in the wider archaeological cluster around Kilballyowen House might use the National Monuments Service database to locate the associated cashel and enclosures, which together suggest this quiet corner of south County Limerick was once a good deal busier than it appears today. The monument record was compiled by Alison McQueen and Vera Rahilly and uploaded in November 2020.