The quince was in the garage for a few days because weather dropped from 70F/15C to 22F/-5C. It came back up to warm Sunday. The first thing I noticed was these bugs all over new leaves, new stems, and flower buds. I sprayed with alcohol and they appeared to die. They came back. I have found large numbers three or four times a day, sprayed each time, and they die and then come back. Yesterday I put the pot in a pan of water blocking ants from crawling up. Later last night they were there agiain; I sprayed, and they returned this morning.
Alcohol isn't the answer. Isolating in a pan of water isn't the answer. What else?