And the name of the query. :P
Do you happen to have both queries in the code, but the second query is after the first one?
Cus if so, once the first query has executed, the WoodType variable will be replaced with that query, and so the second one will fall over when it tries to use the original WoodType string.
(Which is exactly what the error is suggesting.)
A simple way to avoid it is to prefix or suffix all query variables, (so you could call it qryWoodType or WoodTypeQry and it wouldn't conflict with the original WoodType string), or you can give it a completely different name.
EDITED: 21 Apr 2011 13:54 by BOUGHTONP