A possessor of land is subject to liability for bodily harm caused to a trespasser by an artificial condition on the land if (1) the condition is one which the possessor has created or maintains and is, to his knowledge, likely to cause death or serious bodily harm to such trespasser, (2) is of such a nature that he has reason to believe that trespassers will not discover it, and (3) the possessor has failed to exercise reasonable care to warn such trespassers of the condition and the risk involved. Lishinski v. City of Duluth, 634 N.W.2d 456, 458-59 (Minn. App. 2001), review denied (Minn. Jan. 15, 2002).