Concrete pavement and yard intersection

Hello,

Immature flea stages require specific habitat requirements. Our page on where flea larvae live goes into detail on this topic. The larvae page is most informative, because larvae are the most delicate life stage.

To summarize the habitat requirements, the young fleas need shady, wind-protected, humid, warm, food-rich environments. The first 3 of these requirements are related to relative humidity. The larvae can only survive in a relative humidity (RH) above 50%. RH must exceed 45% at all times, even during the hottest parts of the day.

Fleas can’t live in maintained lawns because the habitat isn’t suitable. Too much sunlight and airflow reaches the ground and desiccates the larvae. A study found that larvae will die in Bermuda grass, even in areas beneath trees where there’s abundant shade.

If your patio creates a suitable habitat, fleas could be living there. But another thing to keep in mind is that flea larvae exhibit negative phototaxis, meaning they actively move away from light. They will bury down into the substrate. So most of the fleas wouldn’t be on the concrete surface, but rather inside cracks and crevices.

Further, the larvae need “flea dirt” (blood feces from adult fleas) to consume upon hatching. They will die without it. Fleas lay eggs and defecate on their host. Eggs fall readily because they aren’t sticky. But the feces can get lodged into pet fur upon drying, so most gets released during grooming. As a result, host grooming locations tend to be the best habitats for fleas, as they are rich with eggs and feces. On a concrete patio, the feces (and eggs) would end up accumulating in cracks and crevices.

I am not sure why that flea spray recommends spraying the entire lawn. Perhaps explaining the flea life cycle and habitat requirements is too time consuming for a product label. Also, I am not sure about tick habitats.

I hope this was useful.

Adam