Here is a fall checklist for walnuts offered by Bill Olson, Extension farm advisor in Butte County, Calif.:

- Apply residual herbicides before winter weeds germinate. Remember, water is needed (usually rain) to move the herbicide into the root zone to be effective.

- Prepare new orchard sites or tree sites for planting. This includes soil profile modification fumigation and irrigation system installation.

- Review your grade sheets to develop management strategies for next season.

- Do not apply N fertilizer now. Wait until next spring when leaves are active and N will be taken up readily.