Not exactly burning, but making tar; I'd put it simply 'tar pit' (original Finnish word being tervahauta 'tar grave' lit.), where the resinous/pitchy wood (here in F. only pine is usable) is piled in a cone-formed heap, then covered with soil, lighted from the edge, burned not in flames but slowly, to produce heat enough to the tar to be extracted. You get nice charcoal as side product.

'Tar burning' used to be one of the main export 'industries' of Finland during the sailing ships era, btw.

AKS