Which preposition to use with botanized

in Occurrences 2%

As long as they are in sight, I affect to be diligently botanizing in the hedge.

at Occurrences 1%

After botanizing at this spot, Dr. Houghton remarks, that since arriving at the Ontanagon, he finds plants which belong to a more southerly climate.

under Occurrences 1%

Once, as I was botanizing under an oak, I found amongst a number of other plants of similar height one that was dark in color, with tightly closed leaves and a stalk that was very straight and stiff.

Which preposition to use with  botanized