Flue slope. Question-I've seen this type of venting 3-4 times a month in older houses and never had anyone complain. The bottom metal flue is the 80% furnace with an uphill rise from it to the newly lined masonry chimney (stainless steel liner).
Monarch butterflies utilize different habitat in the warm months versus the cold months. In the spring, summer and early fall, they can be found wherever there are milkweeds. Monarchs lay their eggs on milkweeds and they're always searching for them in fields, meadows and parks.
In tropical lands, butterflies do migrate back and forth as the seasons change. At the beginning of the dry season, the food plants shrivel and the butterflies leave to find a moister climate. When the rains arrive, the food plants grow back and the butterflies return. How do monarchs know when to leave?