I did a sketch with the tree in the composition before I decided to put it in. Looked okay in the sketch but not so much in the painting. It took a lot of scrubbing to eliminate the tree. I then used a hair dryer to get that area VERY dry. I then sprayed the area with a heavy solution of gum arabic which is the “glue” used in and on the paper. That was dried immediately to seal the surface so that the planned wash in that area would match the colors in the background.
I used that same procedure on the weeds on the river bank on the left to simplify the entire foreground
I was able to rewet the area that I scrubbed and match the colors in the rest of the background. I added some very dark trees in that area to get more depth. The horizontal edge of the river bank is also eliminated as well as the weeds on the left.
You would think that painting would be easier after painting for over 50 years!