What's the difference between gnarled and knurled?

Gnarled

Definition:

(imp. & p. p.) of Gnarl
(a.) Knotty; full of knots or gnarls; twisted; crossgrained.

Example Sentences:

(1) Milk has also directed conventional videos for Kanye West, Modest Mouse and Gnarls Barkley.
(2) He has friendly, wide-set eyes, a burst of knotty dreadlocks and a gnarled scar just below his jaw, from when he fell from a low wire as a child and impaled himself on the protruding end of a metal coil.
(3) Every pub draws the audience it deserves, and Bar Fringe's crowd is an unlikely mix of hairy bikers, bohemian folk, gnarled beer-tickers and brainy students, who leave mystifying, maths-related graffiti in the toilets.
(4) Three giant rings glitter on his gnarled fingers as Smokin' Joe, a heavyweight crooner with the blues in his bones, looks up and whoops: "I'm still smokin', man!"
(5) It seems impossible – surely she was ageless, like one of those very old, tiny, trees in the Arctic, gnarled and tough as a nut, but nonetheless evergreen.
(6) And what a face it is: that gnarled, acne-pocked, gin-blossomed lunar landscape of ornery venom and intermittent soulfulness, out of which comes that cantankerous Texan bark.
(7) But the villages seemed much poorer here, some of their roads gnarled up by tanks.
(8) The dendrites have knobby, nodular protuberances which give them a gnarled appearance.
(9) Except that, in Loznitsa's version, the wizard is a disgraced former soldier, the siren a child prostitute and the trolls a trio of gnarled brigands who cook potatoes at a forest campfire and cudgel anyone who draws too close.
(10) As olive branches go it was a particularly twisted and gnarled stick the prime minister held out to his party yesterday.
(11) The concrete building – which was cast on the desert floor in panels and hauled up into place, giving it a gnarled, earthy texture – curves around the theatre’s stepped seating, forming a two-storey crescent (still awaiting its planned third floor).
(12) But it will have the opposite effect on the speech’s detractors, the hard left, the £3 novices who called him a “traitor” on Twitter, the gnarled old Trots who always had their doubts about that bourgeois softie Tony.
(13) NPY-i neurons became distorted, with enlarged misshapen cell somata and reduced, thickened, and gnarled dendrites.
(14) The olivary pretectal nucleus (PO) is characterized by distinctive neurons with a gnarled, tufted, richly branched dendritic arbor forming a dense neuropil within the nucleus.
(15) In an interview with Zane Lowe earlier in the year, Bono said the album had traces of the Ramones and Kraftwerk, and that it was somewhat borne out of self doubt: “We were trying to figure out, ‘Why would anyone want another U2 album?’ ... We felt like we were on the verge of irrelevance.” The album has been produced by Danger Mouse, feted for his duos Gnarls Barkley and Broken Bells as well as work with Jack White and the Black Keys.
(16) But even gnarled park service veterans are impressed at the logistical feats required to maintain plantations as large as 8,700 plants miles from the nearest road.
(17) The forward’s brightness was mirrored around the pitch in what was a less-gnarled United team that had preceded it.
(18) Northern Irish entrepreneur Stephen Gray has even bought a golf course and holiday resort because it is beside the Dark Hedges – a road of tangled, gnarled trees that has become an iconic trail for tourists inspired by the HBO hit.
(19) Covering the CNC-milled polystyrene blocks with plaster and granite sand, they have mimicked the neighbouring gnarled stone even down to the detail of moss, electrostatically flocked onto the surface.
(20) On his return to California, he continued to use his camera as a means to express "the very substance and the quintessence of the thing itself", photographing in close-up what he saw around him: an egg-slicer, a toadstool, a cup, a gnarled tree.