Thank you everyone for all your help! It seems to me that the most reasonable translation is "here" for היער and Leihgestern for לאשדערן.
Here are samples of the place names:
"In 1836 I circumcised his son Yonah, from here."
"I circumcised the boy Kaufman son of Chaim from Leihgestern on Thursday, 13 Shevat, 5611."