Technical Abstract: Methyl bromide has commonly been used to control Replant Disorder when planting a new vineyard into the same field from which an old vineyard was removed. With the ban on import and manufacture scheduled for Jan. 1, 2005, growers need alternatives to methyl bromide for perennial crops that demonstrate efficacy beyond the first growing season. After six growing seasons, a field trial in Parlier, CA demonstrated that drip-applied 1,3-dichloropropene (1,3-D) and shank-injected iodomethane (IM) controlled plant parasitic nematodes comparably to methyl bromide. Harmony, a rootknot-resistant rootstock, remained free of rootknot nematode, Meloidogyne spp., but supported high populations of citrus nematode, Tylenchulus penetrans. Yield of Thompson Seedless and Merlot on Harmony was greatest in plots treated with 1,3-D and IM and least in plots treated with a one-year fallow followed by a cover crop. In a second field trial, the benefit of fallowing up to three years varied by variety/rootstock after four growing seasons. There was no significant reduction in nematodes on Thompson Seedless. There was numerical, but not significant, reduction of rootknot nematode on Teleki 5C. There was no significant differences in yield across length of fallow, untreated, and methyl bromide treatments. In a third field trial, after three growing seasons, IM, 1,3-D + chloropicrin, and propargyl bromide provided comparable nematode control to methyl bromide. Although 1,3-D and IM have shown nematode control comparable to methyl bromide in these trials, there are restrictions on their use. IM is not yet registered and therefore is not available to commercial growers. Use of 1,3-D is limited in California by township caps.