The Collaborative International Dictionary of English v.0.48:

Knobbed \Knobbed\, a.
   Containing knobs; full of knobs; ending in a nob. See Illust
   of Antenna.
   [1913 Webster]

         The horns of a roe deer of Greenland are pointed at the
         top, and knobbed or tuberous at the bottom. --Grew.
   [1913 Webster]

WordNet (r) 3.0 (2006):

knobbed
    adj 1: used of old persons or old trees; covered with knobs or
           knots; "gnarled and knotted hands"; "a knobbed stick"
           [syn: gnarled, gnarly, knotted, knotty,
           knobbed]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "knobbed":
   burled, gnarled, gnarly, knobby, knoblike, knotted, knotty,
   knurled, knurly, nappy, nodal, noded, nodiform, nodular, nodulated,
   noduled, nubbled, nubbly, nubby, pily, pitted, shaggy, studded,
   torose, tubercular, tuberculous, tuberose, tuberous