What brand and gauge strings does Neil Young use on his Martin guitars?

Neil Young is known to use Martin Guitars equipped with custom gauge strings. Specifically, he often uses Martin's own 0.013 to 0.056 gauge strings, which are designed to provide a rich, full sound suitable for his playing style. However, he has also been known to experiment with various string brands and gauges throughout his career, including D'Addario and others, depending on the sound he is seeking for a particular performance or recording.