Mae ffigurau cychwynnol yr Awdurdodau Tân ac Achub ar gyfer 2019 yn dangos y bu 566 o danau glaswellt bwriadol ym mis Ebrill eleni o'i gymharu â 1,292 ym mis Ebrill 2015, sef gostyngiad o 56%. Mae nifer y prif danau glaswellt  – sef y rheini y mae gofyn i 5 neu fwy o beiriannau tân ymateb iddynt, hefyd wedi mwy na haneru, o 50 i 24.
Initial figures from the FRAs for 2019 indicate there were 566 deliberate grass fires in April this year compared to 1,292 in April 2015, a reduction of 56%. Primary grass fires – those which require 5 or more fire appliances to tackle them – also fell by more than half from 50 to 24.