El Cerro Mission's Seasonal Barrier Treatment Team

Most treatments stay effective around 21 days, which is why seasonal programs schedule on that cycle.

Both — barrier spray handles adults while larvicide treats standing water we can't drain. A single missed water source nearby can shorten how long a barrier treatment stays effective, so we always ask about the whole surrounding area, not just the yard itself.

Barrier product follows label guidelines for residential use — we'll note anything needing special handling.

Yes — we schedule timing a day or two before the event for maximum effect on the actual date.

Water features need a different approach — larvicide — because spray only affects adults, not larvae. We can also advise on simple landscaping changes — trimming dense shrubs, thinning standing vegetation — that reduce resting habitat between visits.

A three-week cycle is typical, though heavier rain sometimes calls for tighter scheduling. It also helps to check for new containers holding water after storms, since a single overturned bucket restarts breeding fast.