The HSCA members' notes on this page (62) and two pages later (64) show that they were informed by CIA sources that REDWOOD was defined as the action indicator for the Soviet/Eastern European Division.
Philip Agee, Inside the Company: CIA Diary, p. 60: https://leaksource.files.wordpress.com/2014/08/inside-the-company-cia-diary-philip-agee.pdf
REDWOOD indicates "SR Division action and control".
8/26/63: "CIA advised...Esther Drucker (Bufile 105-12761) while in contact with Ruth Conde (described by MEX-18 and MEX-19 reportedly as a one-time member of the CP, USA in Harlem which is now associated with the ACGM - note: 'Associated Communists in the Government of Mexico') advised that Celia Odenheim had invested in Sam Brooks' last company 'Precisa'.
10/1/63 cable DIR 72865 from DC/SB/CI/G Gardiner ext 6941 to Mexico City, ref 6291, slugline REDWOOD LCIMPROVE: "Coordinating with ACSI Ballou use along lines DIR 69922. Request Ballou give Siderov no indication he witting any sensitive info known to Gen Johnson or other ops data like Siderov love life. Pouching further comment."
11/2/63 cable MEXI 6758, slugline RYBAT KUDESK from Mexico City to Director: "Esther Drucker contacted Lynn Webb 24 Oct regarding tennis date. She wife Lt. Col. George S. Webb Jr. assigned West Point teach English Mexican military academy. Source LIFEAT. Dissem legal attache who transcribes take. View of Drucker commie background security officer military attache Alfred Ballou advised only that Webb wife and Esther Drucker acquainted and he should advise Webb break contact. Source info not to be attributable (CIA) or legal attache. Legal attache sending cable above his hqs. No other dissem. Index. P-981. 201-2589.