Syagrus is a large genus of feather palms from South America related to Butia.  There has been quite a bit of experience with S. romanzoffianum, the most common species, in the Pacific Northwest, and the general consensus is that it will not grow here since winters are a little too cold.  In addition, it also demands quite a bit of summer heat to put on good growth, so it is not really suitable for milder places such as south-west Oregon.  S. romanzoffianum is considered to be overly common in California, but there are lots of other interesting species.  Many of these species are probably even less hardy, but a few species such as S. glaucescens come from very frosty areas of Brazil and may be hardy in a xeric situation in the Pacific Northwest.  It is also thought that the forms of S. romanzoffianum we are presently growing are not from the coldest part of its range, and so there might be some hardier ones out there that remain to be tried.  A microclimate sheltered from the cold and with good heat accumulation is ideal for trying Syagrus.