Burn, then locally known as the Back Burn, and from there it was taken up to Beith by cart. A passenger ferry also ran across the loch at one time, most likely from near the old Lochside Farm, which is reached by a lane from Stonyholm, across to the Bark Mills delta where the silt from the mains burn has encroached into the loch and a small jetty existed. The old Beith Mid Road then led up into the town itself. Natural history Plantations are recorded as having existed at Willowyard near Beith from the 19th century and some woodland policies still survive; the southern end had the Lady Mary's planting, but the northern end was devoid of trees. The old industrial sites on the western shore, for the first 0.75 km or so have substantial Willow plantations and there are some groups of older deciduous trees. Beyond the plantations, and continuing round the loch into the very north-east corner, farmland borders the loch. The Bark Mill near Mains House may be responsible for the loss of the oak trees from around the loch. The virtual absence of emergent vegetation is a characteristic of the loch and may be linked to the consolidated substrate. Castle Semple and Barr Lochs are SSSIs and Kilbirnie Loch is a Scottish Wildlife Trust designated LSNC (Local Site for Nature Conservation) in terms of the Ayrshire Local Biodiversity Action Plan (ALBAP) and in partnership with North Ayrshire Council. High levels of invasive alien waterweed species, Canadian waterweed (Elodea canadensis) and Nuttall’s waterweed (Elodea nuttalli) if left unchecked, will continue to spread and overwhelm other native aquatic plants. The loch's southern end is dominated by large areas of mown grass with mature grown bushes and wood copses. The western shore for the first 0.75 km or so is composed of planted willow with some older deciduous trees; round the loch into the very north-east corner, pastures surround the loch. Along the western part, the ground slopes quite steeply down to the loch. The northern shore itself is level and there are areas of marshy ground. The eastern side of the loch is a narrow strip of reedbed and bogbean grows in sheltered area. The Mains and Willowyard burns feed the loch from the eastern side and the Black Burn enters from the north-west; both have brought in silt that has created the areas of reedbeds. In