Neologism by " with the thumb post " ( up or down ) to be qualified. Can also come from the word ( now disused ) 34, pulgarear " it is a form of pruning the vines.
apulgarado it is incorrectly written and it should be written as "Apurgararse" being its meaning: When an umbrella gets wet, if closed wet, leave you black spots, it is said to be apurgara.a